diff --git a/.gitignore b/.gitignore
index 55eccf8..a008f4f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -47,3 +47,6 @@ templates/**/.claude/commands/speckit*.md
 # Scoped to worktrees/ rather than all of .claude/ so tracked agent config
 # elsewhere in the estate is not silently ignored.
 .claude/worktrees/
+
+# Kotlin compiler daemon session lock files.
+.kotlin/
diff --git a/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/contract/OpenApiSpecExportTest.kt b/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/contract/OpenApiSpecExportTest.kt
index 3d7caba..0116f6a 100644
--- a/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/contract/OpenApiSpecExportTest.kt
+++ b/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/contract/OpenApiSpecExportTest.kt
@@ -6,7 +6,7 @@ import com.jorisjonkers.personalstack.agents.application.RepositoryInstallationS
 import com.jorisjonkers.personalstack.agents.application.RepositoryVerificationService
 import com.jorisjonkers.personalstack.agents.application.chat.ChatAnswerStreamService
 import com.jorisjonkers.personalstack.agents.application.maintenance.RunnerMaintenanceService
-import com.jorisjonkers.personalstack.agents.application.query.ChatSessionQueryService
+import com.jorisjonkers.personalstack.agents.application.query.ConversationQueryService
 import com.jorisjonkers.personalstack.agents.application.query.GetTurnHistoryQueryService
 import com.jorisjonkers.personalstack.agents.application.query.GetWorkspaceQueryService
 import com.jorisjonkers.personalstack.agents.application.query.ListWorkspacesQueryService
@@ -34,6 +34,7 @@ import com.jorisjonkers.personalstack.agents.infrastructure.web.AgentSessionCont
 import com.jorisjonkers.personalstack.agents.infrastructure.web.AgentSetupController
 import com.jorisjonkers.personalstack.agents.infrastructure.web.AgentSetupExceptionHandler
 import com.jorisjonkers.personalstack.agents.infrastructure.web.ChatSessionController
+import com.jorisjonkers.personalstack.agents.infrastructure.web.ConversationController
 import com.jorisjonkers.personalstack.agents.infrastructure.web.CredentialController
 import com.jorisjonkers.personalstack.agents.infrastructure.web.GitController
 import com.jorisjonkers.personalstack.agents.infrastructure.web.HealthController
@@ -77,6 +78,7 @@ import java.nio.file.Paths
         AgentSetupController::class,
         AgentSessionController::class,
         ChatSessionController::class,
+        ConversationController::class,
         CredentialController::class,
         GitController::class,
         HealthController::class,
@@ -112,6 +114,7 @@ import java.nio.file.Paths
         AgentSetupController::class,
         AgentSessionController::class,
         ChatSessionController::class,
+        ConversationController::class,
         CredentialController::class,
         GitController::class,
         HealthController::class,
@@ -246,7 +249,7 @@ class OpenApiSpecExportTest
         @TestConfiguration(proxyBeanMethods = false)
         class QueryCollaborators {
             @Bean
-            fun chatSessionQueryService(): ChatSessionQueryService = mockk(relaxed = true)
+            fun conversationQueryService(): ConversationQueryService = mockk(relaxed = true)
 
             @Bean
             fun getTurnHistoryQueryService(): GetTurnHistoryQueryService = mockk(relaxed = true)
diff --git a/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/flow/AgentsApiContractIntegrationTest.kt b/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/flow/AgentsApiContractIntegrationTest.kt
index 27c72f1..e499d22 100644
--- a/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/flow/AgentsApiContractIntegrationTest.kt
+++ b/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/flow/AgentsApiContractIntegrationTest.kt
@@ -261,6 +261,7 @@ class AgentsApiContractIntegrationTest
             mockMvc
                 .perform(
                     post("/api/v1/chat-sessions/$sessionId/messages")
+                        .header("X-User-Id", userId)
                         .contentType(MediaType.APPLICATION_JSON)
                         .content(
                             objectMapper.writeValueAsString(
@@ -273,9 +274,85 @@ class AgentsApiContractIntegrationTest
                 .andExpect(jsonPath("$.sessionId").value(sessionId))
 
             mockMvc
-                .perform(get("/api/v1/chat-sessions/$sessionId"))
+                .perform(get("/api/v1/chat-sessions/$sessionId").header("X-User-Id", userId))
                 .andExpect(status().isOk)
                 .andExpect(jsonPath("$.session.id").value(sessionId))
                 .andExpect(jsonPath("$.messages[0].body").value("hello world"))
         }
+
+        @Test
+        fun conversationCreationResponseMatchesExpectedSchema() {
+            val userId = UUID.randomUUID().toString()
+            mockMvc
+                .perform(
+                    post("/api/v1/conversations")
+                        .header("X-User-Id", userId)
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(objectMapper.writeValueAsString(mapOf("title" to "Demo chat"))),
+                ).andExpect(status().isCreated)
+                .andExpect(jsonPath("$.id").exists())
+                .andExpect(jsonPath("$.userId").value(userId))
+                .andExpect(jsonPath("$.title").value("Demo chat"))
+                .andExpect(jsonPath("$.status").value("ACTIVE"))
+                .andExpect(jsonPath("$.kind").value("PLAIN"))
+        }
+
+        @Test
+        fun conversationListResponseIsValidJSONArray() {
+            val userId = UUID.randomUUID().toString()
+            mockMvc.perform(
+                post("/api/v1/conversations")
+                    .header("X-User-Id", userId)
+                    .contentType(MediaType.APPLICATION_JSON)
+                    .content(objectMapper.writeValueAsString(mapOf("title" to "List me"))),
+            )
+            mockMvc
+                .perform(get("/api/v1/conversations").header("X-User-Id", userId))
+                .andExpect(status().isOk)
+                .andExpect(jsonPath("$").isArray)
+                .andExpect(jsonPath("$[0].id").exists())
+                .andExpect(jsonPath("$[0].status").exists())
+        }
+
+        @Test
+        fun appendingAConversationMessageReturnsTheTypedEnvelopeAndDetail() {
+            val userId = UUID.randomUUID().toString()
+            val createResult =
+                mockMvc
+                    .perform(
+                        post("/api/v1/conversations")
+                            .header("X-User-Id", userId)
+                            .contentType(MediaType.APPLICATION_JSON)
+                            .content(objectMapper.writeValueAsString(mapOf("title" to "msg-test"))),
+                    ).andExpect(status().isCreated)
+                    .andReturn()
+            val conversationId = objectMapper.readTree(createResult.response.contentAsString)["id"].asText()
+
+            mockMvc
+                .perform(
+                    post("/api/v1/conversations/$conversationId/messages")
+                        .header("X-User-Id", userId)
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(
+                            objectMapper.writeValueAsString(
+                                mapOf("body" to "hello world", "role" to "USER"),
+                            ),
+                        ),
+                ).andExpect(status().isCreated)
+                .andExpect(jsonPath("$.body").value("hello world"))
+                .andExpect(jsonPath("$.role").value("USER"))
+                .andExpect(jsonPath("$.conversationId").value(conversationId))
+
+            mockMvc
+                .perform(get("/api/v1/conversations/$conversationId").header("X-User-Id", userId))
+                .andExpect(status().isOk)
+                .andExpect(jsonPath("$.id").value(conversationId))
+                .andExpect(jsonPath("$.messages[0].body").value("hello world"))
+
+            mockMvc
+                .perform(get("/api/v1/conversations/$conversationId/messages").header("X-User-Id", userId))
+                .andExpect(status().isOk)
+                .andExpect(jsonPath("$[0].body").value("hello world"))
+                .andExpect(jsonPath("$[0].content").value("hello world"))
+        }
     }
diff --git a/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/flow/ConversationOwnershipIntegrationTest.kt b/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/flow/ConversationOwnershipIntegrationTest.kt
new file mode 100644
index 0000000..698e0da
--- /dev/null
+++ b/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/flow/ConversationOwnershipIntegrationTest.kt
@@ -0,0 +1,115 @@
+package com.jorisjonkers.personalstack.agents.flow
+
+import com.fasterxml.jackson.databind.ObjectMapper
+import com.jorisjonkers.personalstack.agents.IntegrationTestBase
+import org.junit.jupiter.api.BeforeEach
+import org.junit.jupiter.api.Test
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.http.MediaType
+import org.springframework.test.web.servlet.MockMvc
+import org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get
+import org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post
+import org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath
+import org.springframework.test.web.servlet.result.MockMvcResultMatchers.status
+import org.springframework.test.web.servlet.setup.MockMvcBuilders
+import org.springframework.web.context.WebApplicationContext
+import java.util.UUID
+
+// Split out from AgentsApiContractIntegrationTest (which was already at
+// detekt's 15-function ceiling): a second user must never read or append
+// to the first user's Conversation, on the canonical path or the
+// deprecated alias (#80).
+class ConversationOwnershipIntegrationTest
+    @Autowired
+    constructor(
+        private val webApplicationContext: WebApplicationContext,
+    ) : IntegrationTestBase {
+        private lateinit var mockMvc: MockMvc
+        private val objectMapper = ObjectMapper()
+
+        @BeforeEach
+        fun setUp() {
+            mockMvc = MockMvcBuilders.webAppContextSetup(webApplicationContext).build()
+        }
+
+        @Test
+        fun aSecondUserCannotReadOrAppendToTheFirstUsersConversation() {
+            val ownerId = UUID.randomUUID().toString()
+            val otherUserId = UUID.randomUUID().toString()
+            val conversationId = createConversation("/api/v1/conversations", ownerId)
+
+            mockMvc
+                .perform(get("/api/v1/conversations/$conversationId").header("X-User-Id", otherUserId))
+                .andExpect(status().isNotFound)
+
+            mockMvc
+                .perform(get("/api/v1/conversations/$conversationId/messages").header("X-User-Id", otherUserId))
+                .andExpect(status().isNotFound)
+
+            mockMvc
+                .perform(
+                    post("/api/v1/conversations/$conversationId/messages")
+                        .header("X-User-Id", otherUserId)
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(objectMapper.writeValueAsString(mapOf("body" to "intruder", "role" to "USER"))),
+                ).andExpect(status().isNotFound)
+
+            mockMvc
+                .perform(
+                    post("/api/v1/conversations/$conversationId/messages/stream")
+                        .header("X-User-Id", otherUserId)
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(objectMapper.writeValueAsString(mapOf("body" to "intruder", "role" to "USER"))),
+                ).andExpect(status().isNotFound)
+
+            mockMvc
+                .perform(get("/api/v1/conversations/$conversationId").header("X-User-Id", ownerId))
+                .andExpect(status().isOk)
+                .andExpect(jsonPath("$.messages").isEmpty)
+
+            mockMvc
+                .perform(get("/api/v1/conversations/$conversationId/messages").header("X-User-Id", ownerId))
+                .andExpect(status().isOk)
+                .andExpect(jsonPath("$").isEmpty)
+        }
+
+        @Test
+        fun aSecondUserCannotReadOrAppendToTheFirstUsersChatSession() {
+            val ownerId = UUID.randomUUID().toString()
+            val otherUserId = UUID.randomUUID().toString()
+            val sessionId = createConversation("/api/v1/chat-sessions", ownerId)
+
+            mockMvc
+                .perform(get("/api/v1/chat-sessions/$sessionId").header("X-User-Id", otherUserId))
+                .andExpect(status().isNotFound)
+
+            mockMvc
+                .perform(
+                    post("/api/v1/chat-sessions/$sessionId/messages")
+                        .header("X-User-Id", otherUserId)
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(objectMapper.writeValueAsString(mapOf("body" to "intruder", "role" to "USER"))),
+                ).andExpect(status().isNotFound)
+
+            mockMvc
+                .perform(get("/api/v1/chat-sessions/$sessionId").header("X-User-Id", ownerId))
+                .andExpect(status().isOk)
+                .andExpect(jsonPath("$.messages").isEmpty)
+        }
+
+        private fun createConversation(
+            basePath: String,
+            ownerId: String,
+        ): String {
+            val createResult =
+                mockMvc
+                    .perform(
+                        post(basePath)
+                            .header("X-User-Id", ownerId)
+                            .contentType(MediaType.APPLICATION_JSON)
+                            .content(objectMapper.writeValueAsString(mapOf("title" to "private"))),
+                    ).andExpect(status().isCreated)
+                    .andReturn()
+            return objectMapper.readTree(createResult.response.contentAsString)["id"].asText()
+        }
+    }
diff --git a/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/persistence/JooqChatMessageRepositoryIntegrationTest.kt b/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/persistence/JooqChatMessageRepositoryIntegrationTest.kt
deleted file mode 100644
index 6eee1cd..0000000
--- a/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/persistence/JooqChatMessageRepositoryIntegrationTest.kt
+++ /dev/null
@@ -1,89 +0,0 @@
-package com.jorisjonkers.personalstack.agents.persistence
-
-import com.jorisjonkers.personalstack.agents.IntegrationTestBase
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessage
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessageId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessageRole
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSession
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionKind
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionStatus
-import com.jorisjonkers.personalstack.agents.domain.port.ChatMessageRepository
-import com.jorisjonkers.personalstack.agents.domain.port.ChatSessionRepository
-import org.assertj.core.api.Assertions.assertThat
-import org.junit.jupiter.api.Test
-import org.springframework.beans.factory.annotation.Autowired
-import java.time.Instant
-import java.util.UUID
-
-class JooqChatMessageRepositoryIntegrationTest
-    @Autowired
-    constructor(
-        private val messages: ChatMessageRepository,
-        private val sessions: ChatSessionRepository,
-    ) : IntegrationTestBase {
-        private fun newSession(): ChatSession =
-            ChatSession(
-                id = ChatSessionId.random(),
-                userId = UUID.randomUUID(),
-                title = "session",
-                status = ChatSessionStatus.ACTIVE,
-                kind = ChatSessionKind.PLAIN,
-                createdAt = Instant.now(),
-                updatedAt = Instant.now(),
-            ).also(sessions::save)
-
-        private fun newMessage(
-            sessionId: ChatSessionId,
-            body: String = "hello",
-            createdAt: Instant = Instant.now(),
-        ) = ChatMessage(
-            id = ChatMessageId.random(),
-            sessionId = sessionId,
-            role = ChatMessageRole.USER,
-            body = body,
-            createdAt = createdAt,
-        )
-
-        @Test
-        fun saveAndFindByIdRoundTrip() {
-            val s = newSession()
-            val m = newMessage(s.id)
-            messages.save(m)
-            val loaded = (messages.findById(m.id)).required()
-            assertThat(loaded.body).isEqualTo("hello")
-        }
-
-        @Test
-        fun findallbysessionidorderedbytimeReturnsMessagesChronologically() {
-            val s = newSession()
-            val first = newMessage(s.id, body = "first", createdAt = Instant.parse("2025-01-01T00:00:00Z"))
-            val second = newMessage(s.id, body = "second", createdAt = Instant.parse("2025-01-01T00:01:00Z"))
-            val third = newMessage(s.id, body = "third", createdAt = Instant.parse("2025-01-01T00:02:00Z"))
-            // Save out of order on purpose.
-            messages.save(third)
-            messages.save(first)
-            messages.save(second)
-
-            val ordered = messages.findAllBySessionIdOrderedByTime(s.id)
-            assertThat(ordered.map { it.body }).containsExactly("first", "second", "third")
-        }
-
-        @Test
-        fun cascadingDeleteRemovesMessagesWhenTheSessionIsRemoved() {
-            val s = newSession()
-            messages.save(newMessage(s.id))
-            messages.save(newMessage(s.id))
-            sessions.delete(s.id)
-            assertThat(messages.findAllBySessionIdOrderedByTime(s.id)).isEmpty()
-        }
-
-        @Test
-        fun deleteallbysessionidRemovesTheRows() {
-            val s = newSession()
-            messages.save(newMessage(s.id))
-            messages.save(newMessage(s.id))
-            messages.deleteAllBySessionId(s.id)
-            assertThat(messages.findAllBySessionIdOrderedByTime(s.id)).isEmpty()
-        }
-    }
diff --git a/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/persistence/JooqChatSessionRepositoryIntegrationTest.kt b/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/persistence/JooqChatSessionRepositoryIntegrationTest.kt
deleted file mode 100644
index 8ecd8be..0000000
--- a/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/persistence/JooqChatSessionRepositoryIntegrationTest.kt
+++ /dev/null
@@ -1,80 +0,0 @@
-package com.jorisjonkers.personalstack.agents.persistence
-
-import com.jorisjonkers.personalstack.agents.IntegrationTestBase
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSession
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionKind
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionStatus
-import com.jorisjonkers.personalstack.agents.domain.port.ChatSessionRepository
-import org.assertj.core.api.Assertions.assertThat
-import org.junit.jupiter.api.Test
-import org.springframework.beans.factory.annotation.Autowired
-import java.time.Instant
-import java.util.UUID
-
-class JooqChatSessionRepositoryIntegrationTest
-    @Autowired
-    constructor(
-        private val sessions: ChatSessionRepository,
-    ) : IntegrationTestBase {
-        private fun newSession(
-            userId: UUID = UUID.randomUUID(),
-            title: String? = "x",
-            kind: ChatSessionKind = ChatSessionKind.PLAIN,
-        ) = ChatSession(
-            id = ChatSessionId.random(),
-            userId = userId,
-            title = title,
-            status = ChatSessionStatus.ACTIVE,
-            kind = kind,
-            createdAt = Instant.now(),
-            updatedAt = Instant.now(),
-        )
-
-        @Test
-        fun saveAndFindByIdRoundTripTheKind() {
-            val s = newSession(kind = ChatSessionKind.KNOWLEDGE)
-            sessions.save(s)
-            assertThat(sessions.findById(s.id).required().kind).isEqualTo(ChatSessionKind.KNOWLEDGE)
-        }
-
-        @Test
-        fun saveAndFindByIdRoundTripWithNullTitle() {
-            val s = newSession(title = null)
-            sessions.save(s)
-            val loaded = (sessions.findById(s.id)).required()
-            assertThat(loaded.title).isNull()
-            assertThat(loaded.status).isEqualTo(ChatSessionStatus.ACTIVE)
-        }
-
-        @Test
-        fun findallbyuseridReturnsOnlyTheUserSSessions() {
-            val userA = UUID.randomUUID()
-            val userB = UUID.randomUUID()
-            sessions.save(newSession(userId = userA, title = "A1"))
-            sessions.save(newSession(userId = userA, title = "A2"))
-            sessions.save(newSession(userId = userB, title = "B"))
-
-            val forA = sessions.findAllByUserId(userA)
-            assertThat(forA).hasSize(2)
-            assertThat(forA.map { it.title }).containsExactlyInAnyOrder("A1", "A2")
-        }
-
-        @Test
-        fun saveUpdatesTheRowOnConflict() {
-            val s = newSession()
-            sessions.save(s)
-            sessions.save(s.copy(status = ChatSessionStatus.ARCHIVED, updatedAt = Instant.now()))
-
-            val loaded = sessions.findById(s.id).required()
-            assertThat(loaded.status).isEqualTo(ChatSessionStatus.ARCHIVED)
-        }
-
-        @Test
-        fun deleteRemovesTheRow() {
-            val s = newSession()
-            sessions.save(s)
-            sessions.delete(s.id)
-            assertThat(sessions.findById(s.id)).isNull()
-        }
-    }
diff --git a/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/persistence/JooqConversationMessageRepositoryIntegrationTest.kt b/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/persistence/JooqConversationMessageRepositoryIntegrationTest.kt
new file mode 100644
index 0000000..1aaa864
--- /dev/null
+++ b/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/persistence/JooqConversationMessageRepositoryIntegrationTest.kt
@@ -0,0 +1,89 @@
+package com.jorisjonkers.personalstack.agents.persistence
+
+import com.jorisjonkers.personalstack.agents.IntegrationTestBase
+import com.jorisjonkers.personalstack.agents.domain.model.Conversation
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationKind
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessage
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageRole
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationStatus
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationMessageRepository
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationRepository
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.Test
+import org.springframework.beans.factory.annotation.Autowired
+import java.time.Instant
+import java.util.UUID
+
+class JooqConversationMessageRepositoryIntegrationTest
+    @Autowired
+    constructor(
+        private val messages: ConversationMessageRepository,
+        private val conversations: ConversationRepository,
+    ) : IntegrationTestBase {
+        private fun newConversation(): Conversation =
+            Conversation(
+                id = ConversationId.random(),
+                userId = UUID.randomUUID(),
+                title = "conversation",
+                status = ConversationStatus.ACTIVE,
+                kind = ConversationKind.PLAIN,
+                createdAt = Instant.now(),
+                updatedAt = Instant.now(),
+            ).also(conversations::save)
+
+        private fun newMessage(
+            conversationId: ConversationId,
+            body: String = "hello",
+            createdAt: Instant = Instant.now(),
+        ) = ConversationMessage(
+            id = ConversationMessageId.random(),
+            conversationId = conversationId,
+            role = ConversationMessageRole.USER,
+            body = body,
+            createdAt = createdAt,
+        )
+
+        @Test
+        fun saveAndFindByIdRoundTrip() {
+            val c = newConversation()
+            val m = newMessage(c.id)
+            messages.save(m)
+            val loaded = (messages.findById(m.id)).required()
+            assertThat(loaded.body).isEqualTo("hello")
+        }
+
+        @Test
+        fun findallbyconversationidorderedbytimeReturnsMessagesChronologically() {
+            val c = newConversation()
+            val first = newMessage(c.id, body = "first", createdAt = Instant.parse("2025-01-01T00:00:00Z"))
+            val second = newMessage(c.id, body = "second", createdAt = Instant.parse("2025-01-01T00:01:00Z"))
+            val third = newMessage(c.id, body = "third", createdAt = Instant.parse("2025-01-01T00:02:00Z"))
+            // Save out of order on purpose.
+            messages.save(third)
+            messages.save(first)
+            messages.save(second)
+
+            val ordered = messages.findAllByConversationIdOrderedByTime(c.id)
+            assertThat(ordered.map { it.body }).containsExactly("first", "second", "third")
+        }
+
+        @Test
+        fun cascadingDeleteRemovesMessagesWhenTheConversationIsRemoved() {
+            val c = newConversation()
+            messages.save(newMessage(c.id))
+            messages.save(newMessage(c.id))
+            conversations.delete(c.id)
+            assertThat(messages.findAllByConversationIdOrderedByTime(c.id)).isEmpty()
+        }
+
+        @Test
+        fun deleteallbyconversationidRemovesTheRows() {
+            val c = newConversation()
+            messages.save(newMessage(c.id))
+            messages.save(newMessage(c.id))
+            messages.deleteAllByConversationId(c.id)
+            assertThat(messages.findAllByConversationIdOrderedByTime(c.id)).isEmpty()
+        }
+    }
diff --git a/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/persistence/JooqConversationRepositoryIntegrationTest.kt b/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/persistence/JooqConversationRepositoryIntegrationTest.kt
new file mode 100644
index 0000000..b6ba510
--- /dev/null
+++ b/api/src/integrationTest/kotlin/com/jorisjonkers/personalstack/agents/persistence/JooqConversationRepositoryIntegrationTest.kt
@@ -0,0 +1,80 @@
+package com.jorisjonkers.personalstack.agents.persistence
+
+import com.jorisjonkers.personalstack.agents.IntegrationTestBase
+import com.jorisjonkers.personalstack.agents.domain.model.Conversation
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationKind
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationStatus
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationRepository
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.Test
+import org.springframework.beans.factory.annotation.Autowired
+import java.time.Instant
+import java.util.UUID
+
+class JooqConversationRepositoryIntegrationTest
+    @Autowired
+    constructor(
+        private val conversations: ConversationRepository,
+    ) : IntegrationTestBase {
+        private fun newConversation(
+            userId: UUID = UUID.randomUUID(),
+            title: String? = "x",
+            kind: ConversationKind = ConversationKind.PLAIN,
+        ) = Conversation(
+            id = ConversationId.random(),
+            userId = userId,
+            title = title,
+            status = ConversationStatus.ACTIVE,
+            kind = kind,
+            createdAt = Instant.now(),
+            updatedAt = Instant.now(),
+        )
+
+        @Test
+        fun saveAndFindByIdRoundTripTheKind() {
+            val c = newConversation(kind = ConversationKind.KNOWLEDGE)
+            conversations.save(c)
+            assertThat(conversations.findById(c.id).required().kind).isEqualTo(ConversationKind.KNOWLEDGE)
+        }
+
+        @Test
+        fun saveAndFindByIdRoundTripWithNullTitle() {
+            val c = newConversation(title = null)
+            conversations.save(c)
+            val loaded = (conversations.findById(c.id)).required()
+            assertThat(loaded.title).isNull()
+            assertThat(loaded.status).isEqualTo(ConversationStatus.ACTIVE)
+        }
+
+        @Test
+        fun findallbyuseridReturnsOnlyTheUserSConversations() {
+            val userA = UUID.randomUUID()
+            val userB = UUID.randomUUID()
+            conversations.save(newConversation(userId = userA, title = "A1"))
+            conversations.save(newConversation(userId = userA, title = "A2"))
+            conversations.save(newConversation(userId = userB, title = "B"))
+
+            val forA = conversations.findAllByUserId(userA)
+            assertThat(forA).hasSize(2)
+            assertThat(forA.map { it.title }).containsExactlyInAnyOrder("A1", "A2")
+        }
+
+        @Test
+        fun saveUpdatesTheRowOnConflict() {
+            val c = newConversation()
+            conversations.save(c)
+            conversations.save(c.copy(status = ConversationStatus.ARCHIVED, updatedAt = Instant.now()))
+
+            val loaded = conversations.findById(c.id).required()
+            assertThat(loaded.status).isEqualTo(ConversationStatus.ARCHIVED)
+        }
+
+        @Test
+        fun deleteRemovesTheRow() {
+            val c = newConversation()
+            conversations.save(c)
+            conversations.delete(c.id)
+            assertThat(conversations.findById(c.id)).isNull()
+        }
+    }
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/chat/ChatAnswerStreamService.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/chat/ChatAnswerStreamService.kt
index d8f21c5..a2d5255 100644
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/chat/ChatAnswerStreamService.kt
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/chat/ChatAnswerStreamService.kt
@@ -1,12 +1,12 @@
 package com.jorisjonkers.personalstack.agents.application.chat
 
-import com.jorisjonkers.personalstack.agents.application.command.AppendChatMessageCommand
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessageId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessageRole
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
+import com.jorisjonkers.personalstack.agents.application.command.AppendConversationMessageCommand
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageRole
 import com.jorisjonkers.personalstack.agents.domain.port.ChatGenerationPort
-import com.jorisjonkers.personalstack.agents.domain.port.ChatMessageRepository
-import com.jorisjonkers.personalstack.agents.domain.port.ChatSessionRepository
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationMessageRepository
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationRepository
 import com.jorisjonkers.personalstack.common.command.CommandBus
 import com.jorisjonkers.personalstack.common.exception.NotFoundException
 import org.springframework.beans.factory.annotation.Qualifier
@@ -17,52 +17,52 @@ import java.util.concurrent.Executor
 
 @Service
 class ChatAnswerStreamService(
-    private val sessions: ChatSessionRepository,
-    private val messages: ChatMessageRepository,
+    private val conversations: ConversationRepository,
+    private val messages: ConversationMessageRepository,
     private val commandBus: CommandBus,
     private val generation: ChatGenerationPort,
     @param:Qualifier("chatStreamExecutor") private val executor: Executor,
 ) {
     fun stream(
-        sessionId: ChatSessionId,
+        conversationId: ConversationId,
         userBody: String,
     ): SseEmitter {
         require(userBody.isNotBlank()) { "chat message body must not be blank" }
-        sessions.findById(sessionId)
-            ?: throw NotFoundException("ChatSession", sessionId.value.toString())
+        conversations.findById(conversationId)
+            ?: throw NotFoundException("Conversation", conversationId.value.toString())
 
         val emitter = SseEmitter(TIMEOUT_MILLIS)
         executor.execute {
-            generateAnswer(sessionId, userBody, emitter)
+            generateAnswer(conversationId, userBody, emitter)
         }
         return emitter
     }
 
     private fun generateAnswer(
-        sessionId: ChatSessionId,
+        conversationId: ConversationId,
         userBody: String,
         emitter: SseEmitter,
     ) {
         runCatching {
-            val prompt = buildPrompt(sessionId, userBody)
+            val prompt = buildPrompt(conversationId, userBody)
             val full =
                 generation.generate(prompt) { piece ->
                     sendEvent(emitter, "chunk", mapOf("text" to piece))
                 }
             check(full.isNotBlank()) { "no answer produced" }
-            persistAgentMessage(sessionId, full, emitter)
+            persistAgentMessage(conversationId, full, emitter)
         }.onFailure {
             sendTerminalError(emitter, it)
         }
     }
 
     private fun buildPrompt(
-        sessionId: ChatSessionId,
+        conversationId: ConversationId,
         userBody: String,
     ): String {
         val history =
             messages
-                .findAllBySessionIdOrderedByTime(sessionId)
+                .findAllByConversationIdOrderedByTime(conversationId)
                 .takeLast(MAX_HISTORY_MESSAGES)
         if (history.isEmpty()) return userBody
 
@@ -70,7 +70,7 @@ class ChatAnswerStreamService(
         // streaming. Only append it when history does not already end with it, so
         // the prompt is identical regardless of persist-then-stream ordering.
         val currentTurnAlreadyPersisted =
-            history.last().let { it.role == ChatMessageRole.USER && it.body == userBody }
+            history.last().let { it.role == ConversationMessageRole.USER && it.body == userBody }
         return buildString {
             for (message in history) {
                 append(labelFor(message.role))
@@ -85,24 +85,24 @@ class ChatAnswerStreamService(
         }.trimEnd('\n')
     }
 
-    private fun labelFor(role: ChatMessageRole): String =
+    private fun labelFor(role: ConversationMessageRole): String =
         when (role) {
-            ChatMessageRole.USER -> "User"
-            ChatMessageRole.ASSISTANT -> "Assistant"
-            ChatMessageRole.SYSTEM -> "System"
+            ConversationMessageRole.USER -> "User"
+            ConversationMessageRole.ASSISTANT -> "Assistant"
+            ConversationMessageRole.SYSTEM -> "System"
         }
 
     private fun persistAgentMessage(
-        sessionId: ChatSessionId,
+        conversationId: ConversationId,
         full: String,
         emitter: SseEmitter,
     ) {
-        val messageId = ChatMessageId.random()
+        val messageId = ConversationMessageId.random()
         commandBus.dispatch(
-            AppendChatMessageCommand(
+            AppendConversationMessageCommand(
                 messageId = messageId,
-                sessionId = sessionId,
-                role = ChatMessageRole.ASSISTANT,
+                conversationId = conversationId,
+                role = ConversationMessageRole.ASSISTANT,
                 body = full,
             ),
         )
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendChatMessageCommand.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendChatMessageCommand.kt
deleted file mode 100644
index 9c53494..0000000
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendChatMessageCommand.kt
+++ /dev/null
@@ -1,13 +0,0 @@
-package com.jorisjonkers.personalstack.agents.application.command
-
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessageId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessageRole
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
-import com.jorisjonkers.personalstack.common.command.Command
-
-data class AppendChatMessageCommand(
-    val messageId: ChatMessageId,
-    val sessionId: ChatSessionId,
-    val role: ChatMessageRole,
-    val body: String,
-) : Command
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendChatMessageCommandHandler.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendChatMessageCommandHandler.kt
deleted file mode 100644
index 94cbbe3..0000000
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendChatMessageCommandHandler.kt
+++ /dev/null
@@ -1,35 +0,0 @@
-package com.jorisjonkers.personalstack.agents.application.command
-
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessage
-import com.jorisjonkers.personalstack.agents.domain.port.ChatMessageRepository
-import com.jorisjonkers.personalstack.agents.domain.port.ChatSessionRepository
-import com.jorisjonkers.personalstack.common.command.CommandHandler
-import com.jorisjonkers.personalstack.common.exception.NotFoundException
-import org.springframework.stereotype.Component
-import org.springframework.transaction.annotation.Transactional
-import java.time.Instant
-
-@Component
-class AppendChatMessageCommandHandler(
-    private val sessions: ChatSessionRepository,
-    private val messages: ChatMessageRepository,
-) : CommandHandler<AppendChatMessageCommand> {
-    @Transactional
-    override fun handle(command: AppendChatMessageCommand) {
-        require(command.body.isNotBlank()) { "chat message body must not be blank" }
-        val session =
-            sessions.findById(command.sessionId)
-                ?: throw NotFoundException("ChatSession", command.sessionId.value.toString())
-        val now = Instant.now()
-        messages.save(
-            ChatMessage(
-                id = command.messageId,
-                sessionId = session.id,
-                role = command.role,
-                body = command.body,
-                createdAt = now,
-            ),
-        )
-        sessions.save(session.copy(updatedAt = now))
-    }
-}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendConversationMessageCommand.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendConversationMessageCommand.kt
new file mode 100644
index 0000000..12ad56b
--- /dev/null
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendConversationMessageCommand.kt
@@ -0,0 +1,13 @@
+package com.jorisjonkers.personalstack.agents.application.command
+
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageRole
+import com.jorisjonkers.personalstack.common.command.Command
+
+data class AppendConversationMessageCommand(
+    val messageId: ConversationMessageId,
+    val conversationId: ConversationId,
+    val role: ConversationMessageRole,
+    val body: String,
+) : Command
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendConversationMessageCommandHandler.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendConversationMessageCommandHandler.kt
new file mode 100644
index 0000000..9c3276a
--- /dev/null
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendConversationMessageCommandHandler.kt
@@ -0,0 +1,35 @@
+package com.jorisjonkers.personalstack.agents.application.command
+
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessage
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationMessageRepository
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationRepository
+import com.jorisjonkers.personalstack.common.command.CommandHandler
+import com.jorisjonkers.personalstack.common.exception.NotFoundException
+import org.springframework.stereotype.Component
+import org.springframework.transaction.annotation.Transactional
+import java.time.Instant
+
+@Component
+class AppendConversationMessageCommandHandler(
+    private val conversations: ConversationRepository,
+    private val messages: ConversationMessageRepository,
+) : CommandHandler<AppendConversationMessageCommand> {
+    @Transactional
+    override fun handle(command: AppendConversationMessageCommand) {
+        require(command.body.isNotBlank()) { "conversation message body must not be blank" }
+        val conversation =
+            conversations.findById(command.conversationId)
+                ?: throw NotFoundException("Conversation", command.conversationId.value.toString())
+        val now = Instant.now()
+        messages.save(
+            ConversationMessage(
+                id = command.messageId,
+                conversationId = conversation.id,
+                role = command.role,
+                body = command.body,
+                createdAt = now,
+            ),
+        )
+        conversations.save(conversation.copy(updatedAt = now))
+    }
+}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveChatSessionCommandHandler.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveChatSessionCommandHandler.kt
deleted file mode 100644
index 6ebb93a..0000000
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveChatSessionCommandHandler.kt
+++ /dev/null
@@ -1,35 +0,0 @@
-package com.jorisjonkers.personalstack.agents.application.command
-
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionStatus
-import com.jorisjonkers.personalstack.agents.domain.port.ChatSessionRepository
-import com.jorisjonkers.personalstack.common.command.CommandHandler
-import com.jorisjonkers.personalstack.common.exception.DomainException
-import com.jorisjonkers.personalstack.common.exception.NotFoundException
-import org.springframework.stereotype.Component
-import org.springframework.transaction.annotation.Transactional
-import java.time.Instant
-
-@Component
-class ArchiveChatSessionCommandHandler(
-    private val sessions: ChatSessionRepository,
-) : CommandHandler<ArchiveChatSessionCommand> {
-    @Transactional
-    override fun handle(command: ArchiveChatSessionCommand) {
-        val session =
-            sessions.findById(command.sessionId)
-                ?: throw NotFoundException("ChatSession", command.sessionId.value.toString())
-
-        if (session.userId != command.userId) {
-            throw DomainException(
-                "User ${command.userId} does not own chat session ${command.sessionId.value}",
-                "FORBIDDEN",
-            )
-        }
-        sessions.save(
-            session.copy(
-                status = ChatSessionStatus.ARCHIVED,
-                updatedAt = Instant.now(),
-            ),
-        )
-    }
-}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveChatSessionCommand.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveConversationCommand.kt
similarity index 54%
rename from api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveChatSessionCommand.kt
rename to api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveConversationCommand.kt
index b29e91d..38f2caa 100644
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveChatSessionCommand.kt
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveConversationCommand.kt
@@ -1,10 +1,10 @@
 package com.jorisjonkers.personalstack.agents.application.command
 
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
 import com.jorisjonkers.personalstack.common.command.Command
 import java.util.UUID
 
-data class ArchiveChatSessionCommand(
-    val sessionId: ChatSessionId,
+data class ArchiveConversationCommand(
+    val conversationId: ConversationId,
     val userId: UUID,
 ) : Command
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveConversationCommandHandler.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveConversationCommandHandler.kt
new file mode 100644
index 0000000..80fba7b
--- /dev/null
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveConversationCommandHandler.kt
@@ -0,0 +1,35 @@
+package com.jorisjonkers.personalstack.agents.application.command
+
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationStatus
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationRepository
+import com.jorisjonkers.personalstack.common.command.CommandHandler
+import com.jorisjonkers.personalstack.common.exception.DomainException
+import com.jorisjonkers.personalstack.common.exception.NotFoundException
+import org.springframework.stereotype.Component
+import org.springframework.transaction.annotation.Transactional
+import java.time.Instant
+
+@Component
+class ArchiveConversationCommandHandler(
+    private val conversations: ConversationRepository,
+) : CommandHandler<ArchiveConversationCommand> {
+    @Transactional
+    override fun handle(command: ArchiveConversationCommand) {
+        val conversation =
+            conversations.findById(command.conversationId)
+                ?: throw NotFoundException("Conversation", command.conversationId.value.toString())
+
+        if (conversation.userId != command.userId) {
+            throw DomainException(
+                "User ${command.userId} does not own conversation ${command.conversationId.value}",
+                "FORBIDDEN",
+            )
+        }
+        conversations.save(
+            conversation.copy(
+                status = ConversationStatus.ARCHIVED,
+                updatedAt = Instant.now(),
+            ),
+        )
+    }
+}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/CreateWorkspaceCommand.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/CreateWorkspaceCommand.kt
index 4d1e889..ceb4cf8 100644
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/CreateWorkspaceCommand.kt
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/CreateWorkspaceCommand.kt
@@ -21,8 +21,8 @@ import com.jorisjonkers.personalstack.common.command.Command
  *    supplied if the operator wants a free-text URL for future
  *    use, but the orchestrator does not act on it.
  *
- * 3. `CHAT`: not handled here — chat lives in [ChatSession] and
- *    is created via [StartChatSessionCommand]. A `kind = CHAT`
+ * 3. `CHAT`: not handled here — chat lives in [Conversation] and
+ *    is created via [StartConversationCommand]. A `kind = CHAT`
  *    workspace creation request is rejected.
  *
  * [projectId] is optional context: setting it groups the workspace
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/CreateWorkspaceCommandHandler.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/CreateWorkspaceCommandHandler.kt
index 340616e..d8409d2 100644
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/CreateWorkspaceCommandHandler.kt
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/CreateWorkspaceCommandHandler.kt
@@ -55,7 +55,7 @@ class CreateWorkspaceCommandHandler(
 
     override fun handle(command: CreateWorkspaceCommand) {
         require(command.kind != WorkspaceKind.CHAT) {
-            "CHAT workspaces are not persisted — use StartChatSessionCommand instead"
+            "CHAT workspaces are not persisted — use StartConversationCommand instead"
         }
         warnDeprecatedGithubLink(command)
         val resolved = resolveRepo(command)
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartChatSessionCommand.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartChatSessionCommand.kt
deleted file mode 100644
index 8a0b2e8..0000000
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartChatSessionCommand.kt
+++ /dev/null
@@ -1,13 +0,0 @@
-package com.jorisjonkers.personalstack.agents.application.command
-
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionKind
-import com.jorisjonkers.personalstack.common.command.Command
-import java.util.UUID
-
-data class StartChatSessionCommand(
-    val sessionId: ChatSessionId,
-    val userId: UUID,
-    val title: String? = null,
-    val kind: ChatSessionKind = ChatSessionKind.PLAIN,
-) : Command
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartConversationCommand.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartConversationCommand.kt
new file mode 100644
index 0000000..4e95429
--- /dev/null
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartConversationCommand.kt
@@ -0,0 +1,13 @@
+package com.jorisjonkers.personalstack.agents.application.command
+
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationKind
+import com.jorisjonkers.personalstack.common.command.Command
+import java.util.UUID
+
+data class StartConversationCommand(
+    val conversationId: ConversationId,
+    val userId: UUID,
+    val title: String? = null,
+    val kind: ConversationKind = ConversationKind.PLAIN,
+) : Command
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartChatSessionCommandHandler.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartConversationCommandHandler.kt
similarity index 52%
rename from api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartChatSessionCommandHandler.kt
rename to api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartConversationCommandHandler.kt
index 7159829..88023ee 100644
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartChatSessionCommandHandler.kt
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartConversationCommandHandler.kt
@@ -1,32 +1,32 @@
 package com.jorisjonkers.personalstack.agents.application.command
 
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSession
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionStatus
-import com.jorisjonkers.personalstack.agents.domain.port.ChatSessionRepository
+import com.jorisjonkers.personalstack.agents.domain.model.Conversation
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationStatus
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationRepository
 import com.jorisjonkers.personalstack.common.command.CommandHandler
 import org.springframework.stereotype.Component
 import org.springframework.transaction.annotation.Transactional
 import java.time.Instant
 
 /**
- * Spawns a no-Pod chat session for a user. Returns nothing; the
+ * Starts a no-Pod conversation for a user. Returns nothing; the
  * caller passes the freshly generated id in so a follow-up read can
  * locate the new row.
  */
 @Component
-class StartChatSessionCommandHandler(
-    private val sessions: ChatSessionRepository,
-) : CommandHandler<StartChatSessionCommand> {
+class StartConversationCommandHandler(
+    private val conversations: ConversationRepository,
+) : CommandHandler<StartConversationCommand> {
     @Transactional
-    override fun handle(command: StartChatSessionCommand) {
+    override fun handle(command: StartConversationCommand) {
         val now = Instant.now()
         val title = command.title?.trim()?.takeIf { it.isNotEmpty() }
-        sessions.save(
-            ChatSession(
-                id = command.sessionId,
+        conversations.save(
+            Conversation(
+                id = command.conversationId,
                 userId = command.userId,
                 title = title,
-                status = ChatSessionStatus.ACTIVE,
+                status = ConversationStatus.ACTIVE,
                 kind = command.kind,
                 createdAt = now,
                 updatedAt = now,
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/query/ChatSessionQueryService.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/query/ChatSessionQueryService.kt
deleted file mode 100644
index 1e5ebc4..0000000
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/query/ChatSessionQueryService.kt
+++ /dev/null
@@ -1,27 +0,0 @@
-package com.jorisjonkers.personalstack.agents.application.query
-
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessage
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSession
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
-import com.jorisjonkers.personalstack.agents.domain.port.ChatMessageRepository
-import com.jorisjonkers.personalstack.agents.domain.port.ChatSessionRepository
-import org.springframework.stereotype.Service
-import java.util.UUID
-
-@Service
-class ChatSessionQueryService(
-    private val sessions: ChatSessionRepository,
-    private val messages: ChatMessageRepository,
-) {
-    data class ChatSessionDetail(
-        val session: ChatSession,
-        val messages: List<ChatMessage>,
-    )
-
-    fun list(userId: UUID): List<ChatSession> = sessions.findAllByUserId(userId)
-
-    fun get(id: ChatSessionId): ChatSessionDetail? {
-        val session = sessions.findById(id) ?: return null
-        return ChatSessionDetail(session, messages.findAllBySessionIdOrderedByTime(id))
-    }
-}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/query/ConversationQueryService.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/query/ConversationQueryService.kt
new file mode 100644
index 0000000..ebc1788
--- /dev/null
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/application/query/ConversationQueryService.kt
@@ -0,0 +1,40 @@
+package com.jorisjonkers.personalstack.agents.application.query
+
+import com.jorisjonkers.personalstack.agents.domain.model.Conversation
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessage
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationMessageRepository
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationRepository
+import org.slf4j.LoggerFactory
+import org.springframework.stereotype.Service
+import java.util.UUID
+
+@Service
+class ConversationQueryService(
+    private val conversations: ConversationRepository,
+    private val messages: ConversationMessageRepository,
+) {
+    private val log = LoggerFactory.getLogger(ConversationQueryService::class.java)
+
+    data class ConversationDetail(
+        val conversation: Conversation,
+        val messages: List<ConversationMessage>,
+    )
+
+    fun list(userId: UUID): List<Conversation> = conversations.findAllByUserId(userId)
+
+    // Returns nothing for another user's Conversation, identically to an
+    // unknown id: this is the single seam every handler reads through, so
+    // ownership can never be forgotten by a caller (see #80).
+    fun get(
+        id: ConversationId,
+        userId: UUID,
+    ): ConversationDetail? {
+        val conversation = conversations.findById(id) ?: return null
+        if (conversation.userId != userId) {
+            log.warn("refused conversation {} for user {}: not the owner", id.value, userId)
+            return null
+        }
+        return ConversationDetail(conversation, messages.findAllByConversationIdOrderedByTime(id))
+    }
+}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatMessage.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatMessage.kt
deleted file mode 100644
index 1b9a879..0000000
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatMessage.kt
+++ /dev/null
@@ -1,11 +0,0 @@
-package com.jorisjonkers.personalstack.agents.domain.model
-
-import java.time.Instant
-
-data class ChatMessage(
-    val id: ChatMessageId,
-    val sessionId: ChatSessionId,
-    val role: ChatMessageRole,
-    val body: String,
-    val createdAt: Instant,
-)
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatMessageId.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatMessageId.kt
deleted file mode 100644
index c4411ea..0000000
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatMessageId.kt
+++ /dev/null
@@ -1,16 +0,0 @@
-package com.jorisjonkers.personalstack.agents.domain.model
-
-import java.util.UUID
-
-@JvmInline
-value class ChatMessageId(
-    val value: UUID,
-) {
-    override fun toString(): String = value.toString()
-
-    companion object {
-        fun random(): ChatMessageId = ChatMessageId(UUID.randomUUID())
-
-        fun parse(s: String): ChatMessageId = ChatMessageId(UUID.fromString(s))
-    }
-}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatSession.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatSession.kt
deleted file mode 100644
index 3948b5e..0000000
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatSession.kt
+++ /dev/null
@@ -1,22 +0,0 @@
-package com.jorisjonkers.personalstack.agents.domain.model
-
-import java.time.Instant
-import java.util.UUID
-
-/**
- * Chat sessions are the no-Pod conversation surface. They live next
- * to [Conversation] — the older type that the legacy chat UI still
- * writes against — and exist so the redesigned UI can surface
- * "chat" / "scratch" / "workspace" as three sibling tabs without
- * coupling each tab to a Pod lifecycle. The legacy `conversations`
- * table stays for the rollout window.
- */
-data class ChatSession(
-    val id: ChatSessionId,
-    val userId: UUID,
-    val title: String?,
-    val status: ChatSessionStatus,
-    val kind: ChatSessionKind,
-    val createdAt: Instant,
-    val updatedAt: Instant,
-)
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatSessionKind.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatSessionKind.kt
deleted file mode 100644
index 493e913..0000000
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatSessionKind.kt
+++ /dev/null
@@ -1,17 +0,0 @@
-package com.jorisjonkers.personalstack.agents.domain.model
-
-/**
- * What a chat session is wired to talk to.
- *
- * - [PLAIN] — the existing no-Pod conversation surface: messages are
- *   persisted and nothing else happens server-side.
- * - [KNOWLEDGE] — a session that operates on the knowledge base via an
- *   agent-runner Pod calling the `knowledge.*` MCP tools. The Pod
- *   binding + streaming land in a follow-up; this value lets the
- *   redesigned UI mark a session as KB-mode and lets the backend route
- *   on it without a second migration later.
- */
-enum class ChatSessionKind {
-    PLAIN,
-    KNOWLEDGE,
-}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/Conversation.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/Conversation.kt
new file mode 100644
index 0000000..b3a240a
--- /dev/null
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/Conversation.kt
@@ -0,0 +1,20 @@
+package com.jorisjonkers.personalstack.agents.domain.model
+
+import java.time.Instant
+import java.util.UUID
+
+/**
+ * The no-Pod chat surface: a chat between the user and an agent that
+ * has no Workspace. Formerly `ChatSession`, renamed onto this name
+ * once the legacy `conversation` table (a different, unrelated model)
+ * was dropped.
+ */
+data class Conversation(
+    val id: ConversationId,
+    val userId: UUID,
+    val title: String?,
+    val status: ConversationStatus,
+    val kind: ConversationKind,
+    val createdAt: Instant,
+    val updatedAt: Instant,
+)
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatSessionId.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationId.kt
similarity index 53%
rename from api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatSessionId.kt
rename to api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationId.kt
index 5b9ea89..b7fe3a7 100644
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatSessionId.kt
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationId.kt
@@ -3,14 +3,14 @@ package com.jorisjonkers.personalstack.agents.domain.model
 import java.util.UUID
 
 @JvmInline
-value class ChatSessionId(
+value class ConversationId(
     val value: UUID,
 ) {
     override fun toString(): String = value.toString()
 
     companion object {
-        fun random(): ChatSessionId = ChatSessionId(UUID.randomUUID())
+        fun random(): ConversationId = ConversationId(UUID.randomUUID())
 
-        fun parse(s: String): ChatSessionId = ChatSessionId(UUID.fromString(s))
+        fun parse(s: String): ConversationId = ConversationId(UUID.fromString(s))
     }
 }
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationKind.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationKind.kt
new file mode 100644
index 0000000..a5e9cae
--- /dev/null
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationKind.kt
@@ -0,0 +1,17 @@
+package com.jorisjonkers.personalstack.agents.domain.model
+
+/**
+ * What a conversation is wired to talk to.
+ *
+ * - [PLAIN] — the no-Pod conversation surface: messages are persisted
+ *   and nothing else happens server-side.
+ * - [KNOWLEDGE] — a conversation that operates on the knowledge base via
+ *   an agent-runner Pod calling the `knowledge.*` MCP tools. The Pod
+ *   binding + streaming land in a follow-up; this value lets the
+ *   redesigned UI mark a conversation as KB-mode and lets the backend
+ *   route on it without a second migration later.
+ */
+enum class ConversationKind {
+    PLAIN,
+    KNOWLEDGE,
+}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationMessage.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationMessage.kt
new file mode 100644
index 0000000..910ca4b
--- /dev/null
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationMessage.kt
@@ -0,0 +1,11 @@
+package com.jorisjonkers.personalstack.agents.domain.model
+
+import java.time.Instant
+
+data class ConversationMessage(
+    val id: ConversationMessageId,
+    val conversationId: ConversationId,
+    val role: ConversationMessageRole,
+    val body: String,
+    val createdAt: Instant,
+)
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationMessageId.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationMessageId.kt
new file mode 100644
index 0000000..00d01f0
--- /dev/null
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationMessageId.kt
@@ -0,0 +1,16 @@
+package com.jorisjonkers.personalstack.agents.domain.model
+
+import java.util.UUID
+
+@JvmInline
+value class ConversationMessageId(
+    val value: UUID,
+) {
+    override fun toString(): String = value.toString()
+
+    companion object {
+        fun random(): ConversationMessageId = ConversationMessageId(UUID.randomUUID())
+
+        fun parse(s: String): ConversationMessageId = ConversationMessageId(UUID.fromString(s))
+    }
+}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatMessageRole.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationMessageRole.kt
similarity index 72%
rename from api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatMessageRole.kt
rename to api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationMessageRole.kt
index 30cc64e..52f7400 100644
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatMessageRole.kt
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationMessageRole.kt
@@ -1,6 +1,6 @@
 package com.jorisjonkers.personalstack.agents.domain.model
 
-enum class ChatMessageRole {
+enum class ConversationMessageRole {
     USER,
     ASSISTANT,
     SYSTEM,
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatSessionStatus.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationStatus.kt
similarity index 73%
rename from api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatSessionStatus.kt
rename to api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationStatus.kt
index 717e9ef..55f377b 100644
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ChatSessionStatus.kt
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/ConversationStatus.kt
@@ -1,6 +1,6 @@
 package com.jorisjonkers.personalstack.agents.domain.model
 
-enum class ChatSessionStatus {
+enum class ConversationStatus {
     ACTIVE,
     ARCHIVED,
 }
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/Workspace.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/Workspace.kt
index 631ce0e..00be8cd 100644
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/Workspace.kt
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/Workspace.kt
@@ -14,7 +14,7 @@ enum class RunnerSetupOperation { IDLE, RESTARTING, FAILED }
  *   a workspace-scoped k8s Secret.
  * - `SCRATCH`     — Pod without a clone. `repositoryId` is null.
  * - `CHAT`        — never actually persisted as a workspace row
- *   today; chat lives in its own [ChatSession] table. The enum
+ *   today; chat lives in its own [Conversation] table. The enum
  *   value exists for type-symmetry with the UI tabs.
  *
  * `projectId` is set when the workspace was opened "inside a
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/WorkspaceKind.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/WorkspaceKind.kt
index 6f2afbb..46ac252 100644
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/WorkspaceKind.kt
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/model/WorkspaceKind.kt
@@ -7,7 +7,7 @@ package com.jorisjonkers.personalstack.agents.domain.model
  * - `SCRATCH`     — Pod without a clone. Repository is null.
  * - `CHAT`        — no Pod. A plain LLM conversation surface that
  *                   lives outside the workspaces table (see
- *                   [ChatSession]); the enum value exists here so a
+ *                   [Conversation]); the enum value exists here so a
  *                   workspace row with `kind = CHAT` can never be
  *                   created — the type system gives the orchestrator
  *                   a single value to switch on.
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/port/ChatMessageRepository.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/port/ChatMessageRepository.kt
deleted file mode 100644
index f787080..0000000
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/port/ChatMessageRepository.kt
+++ /dev/null
@@ -1,15 +0,0 @@
-package com.jorisjonkers.personalstack.agents.domain.port
-
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessage
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessageId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
-
-interface ChatMessageRepository {
-    fun save(message: ChatMessage): ChatMessage
-
-    fun findById(id: ChatMessageId): ChatMessage?
-
-    fun findAllBySessionIdOrderedByTime(sessionId: ChatSessionId): List<ChatMessage>
-
-    fun deleteAllBySessionId(sessionId: ChatSessionId)
-}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/port/ChatSessionRepository.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/port/ChatSessionRepository.kt
deleted file mode 100644
index 8040505..0000000
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/port/ChatSessionRepository.kt
+++ /dev/null
@@ -1,15 +0,0 @@
-package com.jorisjonkers.personalstack.agents.domain.port
-
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSession
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
-import java.util.UUID
-
-interface ChatSessionRepository {
-    fun save(session: ChatSession): ChatSession
-
-    fun findById(id: ChatSessionId): ChatSession?
-
-    fun findAllByUserId(userId: UUID): List<ChatSession>
-
-    fun delete(id: ChatSessionId)
-}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/port/ConversationMessageRepository.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/port/ConversationMessageRepository.kt
new file mode 100644
index 0000000..814471f
--- /dev/null
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/port/ConversationMessageRepository.kt
@@ -0,0 +1,15 @@
+package com.jorisjonkers.personalstack.agents.domain.port
+
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessage
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageId
+
+interface ConversationMessageRepository {
+    fun save(message: ConversationMessage): ConversationMessage
+
+    fun findById(id: ConversationMessageId): ConversationMessage?
+
+    fun findAllByConversationIdOrderedByTime(conversationId: ConversationId): List<ConversationMessage>
+
+    fun deleteAllByConversationId(conversationId: ConversationId)
+}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/port/ConversationRepository.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/port/ConversationRepository.kt
new file mode 100644
index 0000000..60e229a
--- /dev/null
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/domain/port/ConversationRepository.kt
@@ -0,0 +1,15 @@
+package com.jorisjonkers.personalstack.agents.domain.port
+
+import com.jorisjonkers.personalstack.agents.domain.model.Conversation
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import java.util.UUID
+
+interface ConversationRepository {
+    fun save(conversation: Conversation): Conversation
+
+    fun findById(id: ConversationId): Conversation?
+
+    fun findAllByUserId(userId: UUID): List<Conversation>
+
+    fun delete(id: ConversationId)
+}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/persistence/JooqChatMessageRepository.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/persistence/JooqChatMessageRepository.kt
deleted file mode 100644
index c875409..0000000
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/persistence/JooqChatMessageRepository.kt
+++ /dev/null
@@ -1,77 +0,0 @@
-package com.jorisjonkers.personalstack.agents.infrastructure.persistence
-
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessage
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessageId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessageRole
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
-import com.jorisjonkers.personalstack.agents.domain.port.ChatMessageRepository
-import org.jooq.DSLContext
-import org.jooq.Record
-import org.jooq.impl.DSL
-import org.springframework.stereotype.Repository
-import java.time.OffsetDateTime
-import java.time.ZoneOffset
-import java.util.UUID
-
-@Repository
-class JooqChatMessageRepository(
-    private val dsl: DSLContext,
-) : ChatMessageRepository {
-    override fun save(message: ChatMessage): ChatMessage {
-        val createdAt = message.createdAt.atOffset(ZoneOffset.UTC)
-        dsl
-            .insertInto(TABLE)
-            .set(ID, message.id.value)
-            .set(SESSION_ID, message.sessionId.value)
-            .set(ROLE, message.role.name)
-            .set(BODY, message.body)
-            .set(CREATED_AT, createdAt)
-            .onConflict(ID)
-            .doUpdate()
-            .set(BODY, message.body)
-            .execute()
-        return message
-    }
-
-    override fun findById(id: ChatMessageId): ChatMessage? =
-        dsl
-            .selectFrom(TABLE)
-            .where(ID.eq(id.value))
-            .fetchOne()
-            ?.toMessage()
-
-    override fun findAllBySessionIdOrderedByTime(sessionId: ChatSessionId): List<ChatMessage> =
-        dsl
-            .selectFrom(TABLE)
-            .where(SESSION_ID.eq(sessionId.value))
-            .orderBy(CREATED_AT.asc())
-            .fetch()
-            .map { it.toMessage() }
-
-    override fun deleteAllBySessionId(sessionId: ChatSessionId) {
-        dsl.deleteFrom(TABLE).where(SESSION_ID.eq(sessionId.value)).execute()
-    }
-
-    private fun Record.toMessage(): ChatMessage =
-        ChatMessage(
-            id = ChatMessageId(this[ID]),
-            sessionId = ChatSessionId(this[SESSION_ID]),
-            role = ChatMessageRole.valueOf(this[ROLE]),
-            body = this[BODY],
-            createdAt = this[CREATED_AT].toInstant(),
-        )
-
-    companion object {
-        @JvmStatic val TABLE = DSL.table("chat_session_messages")
-
-        @JvmStatic val ID = DSL.field("id", UUID::class.java)
-
-        @JvmStatic val SESSION_ID = DSL.field("chat_session_id", UUID::class.java)
-
-        @JvmStatic val ROLE = DSL.field("role", String::class.java)
-
-        @JvmStatic val BODY = DSL.field("body", String::class.java)
-
-        @JvmStatic val CREATED_AT = DSL.field("created_at", OffsetDateTime::class.java)
-    }
-}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/persistence/JooqConversationMessageRepository.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/persistence/JooqConversationMessageRepository.kt
new file mode 100644
index 0000000..c7ec13e
--- /dev/null
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/persistence/JooqConversationMessageRepository.kt
@@ -0,0 +1,77 @@
+package com.jorisjonkers.personalstack.agents.infrastructure.persistence
+
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessage
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageRole
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationMessageRepository
+import org.jooq.DSLContext
+import org.jooq.Record
+import org.jooq.impl.DSL
+import org.springframework.stereotype.Repository
+import java.time.OffsetDateTime
+import java.time.ZoneOffset
+import java.util.UUID
+
+@Repository
+class JooqConversationMessageRepository(
+    private val dsl: DSLContext,
+) : ConversationMessageRepository {
+    override fun save(message: ConversationMessage): ConversationMessage {
+        val createdAt = message.createdAt.atOffset(ZoneOffset.UTC)
+        dsl
+            .insertInto(TABLE)
+            .set(ID, message.id.value)
+            .set(CONVERSATION_ID, message.conversationId.value)
+            .set(ROLE, message.role.name)
+            .set(BODY, message.body)
+            .set(CREATED_AT, createdAt)
+            .onConflict(ID)
+            .doUpdate()
+            .set(BODY, message.body)
+            .execute()
+        return message
+    }
+
+    override fun findById(id: ConversationMessageId): ConversationMessage? =
+        dsl
+            .selectFrom(TABLE)
+            .where(ID.eq(id.value))
+            .fetchOne()
+            ?.toMessage()
+
+    override fun findAllByConversationIdOrderedByTime(conversationId: ConversationId): List<ConversationMessage> =
+        dsl
+            .selectFrom(TABLE)
+            .where(CONVERSATION_ID.eq(conversationId.value))
+            .orderBy(CREATED_AT.asc())
+            .fetch()
+            .map { it.toMessage() }
+
+    override fun deleteAllByConversationId(conversationId: ConversationId) {
+        dsl.deleteFrom(TABLE).where(CONVERSATION_ID.eq(conversationId.value)).execute()
+    }
+
+    private fun Record.toMessage(): ConversationMessage =
+        ConversationMessage(
+            id = ConversationMessageId(this[ID]),
+            conversationId = ConversationId(this[CONVERSATION_ID]),
+            role = ConversationMessageRole.valueOf(this[ROLE]),
+            body = this[BODY],
+            createdAt = this[CREATED_AT].toInstant(),
+        )
+
+    companion object {
+        @JvmStatic val TABLE = DSL.table("conversation_messages")
+
+        @JvmStatic val ID = DSL.field("id", UUID::class.java)
+
+        @JvmStatic val CONVERSATION_ID = DSL.field("conversation_id", UUID::class.java)
+
+        @JvmStatic val ROLE = DSL.field("role", String::class.java)
+
+        @JvmStatic val BODY = DSL.field("body", String::class.java)
+
+        @JvmStatic val CREATED_AT = DSL.field("created_at", OffsetDateTime::class.java)
+    }
+}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/persistence/JooqChatSessionRepository.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/persistence/JooqConversationRepository.kt
similarity index 51%
rename from api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/persistence/JooqChatSessionRepository.kt
rename to api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/persistence/JooqConversationRepository.kt
index 8a93bff..f3c04e2 100644
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/persistence/JooqChatSessionRepository.kt
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/persistence/JooqConversationRepository.kt
@@ -1,10 +1,10 @@
 package com.jorisjonkers.personalstack.agents.infrastructure.persistence
 
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSession
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionKind
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionStatus
-import com.jorisjonkers.personalstack.agents.domain.port.ChatSessionRepository
+import com.jorisjonkers.personalstack.agents.domain.model.Conversation
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationKind
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationStatus
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationRepository
 import org.jooq.DSLContext
 import org.jooq.Record
 import org.jooq.impl.DSL
@@ -14,62 +14,62 @@ import java.time.ZoneOffset
 import java.util.UUID
 
 @Repository
-class JooqChatSessionRepository(
+class JooqConversationRepository(
     private val dsl: DSLContext,
-) : ChatSessionRepository {
-    override fun save(session: ChatSession): ChatSession {
-        val createdAt = session.createdAt.atOffset(ZoneOffset.UTC)
-        val updatedAt = session.updatedAt.atOffset(ZoneOffset.UTC)
+) : ConversationRepository {
+    override fun save(conversation: Conversation): Conversation {
+        val createdAt = conversation.createdAt.atOffset(ZoneOffset.UTC)
+        val updatedAt = conversation.updatedAt.atOffset(ZoneOffset.UTC)
         dsl
             .insertInto(TABLE)
-            .set(ID, session.id.value)
-            .set(USER_ID, session.userId)
-            .set(TITLE, session.title)
-            .set(STATUS, session.status.name)
-            .set(KIND, session.kind.name)
+            .set(ID, conversation.id.value)
+            .set(USER_ID, conversation.userId)
+            .set(TITLE, conversation.title)
+            .set(STATUS, conversation.status.name)
+            .set(KIND, conversation.kind.name)
             .set(CREATED_AT, createdAt)
             .set(UPDATED_AT, updatedAt)
             .onConflict(ID)
             .doUpdate()
-            .set(TITLE, session.title)
-            .set(STATUS, session.status.name)
+            .set(TITLE, conversation.title)
+            .set(STATUS, conversation.status.name)
             .set(UPDATED_AT, updatedAt)
             .execute()
-        return session
+        return conversation
     }
 
-    override fun findById(id: ChatSessionId): ChatSession? =
+    override fun findById(id: ConversationId): Conversation? =
         dsl
             .selectFrom(TABLE)
             .where(ID.eq(id.value))
             .fetchOne()
-            ?.toSession()
+            ?.toConversation()
 
-    override fun findAllByUserId(userId: UUID): List<ChatSession> =
+    override fun findAllByUserId(userId: UUID): List<Conversation> =
         dsl
             .selectFrom(TABLE)
             .where(USER_ID.eq(userId))
             .orderBy(CREATED_AT.desc())
             .fetch()
-            .map { it.toSession() }
+            .map { it.toConversation() }
 
-    override fun delete(id: ChatSessionId) {
+    override fun delete(id: ConversationId) {
         dsl.deleteFrom(TABLE).where(ID.eq(id.value)).execute()
     }
 
-    private fun Record.toSession(): ChatSession =
-        ChatSession(
-            id = ChatSessionId(this[ID]),
+    private fun Record.toConversation(): Conversation =
+        Conversation(
+            id = ConversationId(this[ID]),
             userId = this[USER_ID],
             title = this[TITLE],
-            status = ChatSessionStatus.valueOf(this[STATUS]),
-            kind = ChatSessionKind.valueOf(this[KIND]),
+            status = ConversationStatus.valueOf(this[STATUS]),
+            kind = ConversationKind.valueOf(this[KIND]),
             createdAt = this[CREATED_AT].toInstant(),
             updatedAt = this[UPDATED_AT].toInstant(),
         )
 
     companion object {
-        @JvmStatic val TABLE = DSL.table("chat_sessions")
+        @JvmStatic val TABLE = DSL.table("conversations")
 
         @JvmStatic val ID = DSL.field("id", UUID::class.java)
 
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/ChatSessionController.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/ChatSessionController.kt
index eb9813f..75d0e7c 100644
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/ChatSessionController.kt
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/ChatSessionController.kt
@@ -1,13 +1,13 @@
 package com.jorisjonkers.personalstack.agents.infrastructure.web
 
 import com.jorisjonkers.personalstack.agents.application.chat.ChatAnswerStreamService
-import com.jorisjonkers.personalstack.agents.application.command.AppendChatMessageCommand
-import com.jorisjonkers.personalstack.agents.application.command.ArchiveChatSessionCommand
-import com.jorisjonkers.personalstack.agents.application.command.StartChatSessionCommand
-import com.jorisjonkers.personalstack.agents.application.query.ChatSessionQueryService
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessageId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionKind
+import com.jorisjonkers.personalstack.agents.application.command.AppendConversationMessageCommand
+import com.jorisjonkers.personalstack.agents.application.command.ArchiveConversationCommand
+import com.jorisjonkers.personalstack.agents.application.command.StartConversationCommand
+import com.jorisjonkers.personalstack.agents.application.query.ConversationQueryService
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationKind
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageId
 import com.jorisjonkers.personalstack.agents.infrastructure.web.dto.AppendChatMessageRequest
 import com.jorisjonkers.personalstack.agents.infrastructure.web.dto.ChatMessageResponse
 import com.jorisjonkers.personalstack.agents.infrastructure.web.dto.ChatSessionResponse
@@ -29,88 +29,118 @@ import org.springframework.web.bind.annotation.RestController
 import org.springframework.web.servlet.mvc.method.annotation.SseEmitter
 import java.util.UUID
 
+/**
+ * Deprecated alias for [ConversationController] at the old path.
+ * Serves the same Conversation model with the pre-rename shapes so
+ * agents-ui keeps working unchanged; remove once agents-ui migrates to
+ * /api/v1/conversations.
+ */
 @RestController
 @RequestMapping("/api/v1/chat-sessions")
 class ChatSessionController(
     private val commandBus: CommandBus,
-    private val chatSessionQuery: ChatSessionQueryService,
+    private val conversationQuery: ConversationQueryService,
     private val chatAnswerStream: ChatAnswerStreamService,
 ) {
     @PostMapping
+    @Deprecated("Use POST /api/v1/conversations.")
     fun create(
         @RequestHeader("X-User-Id") userId: String,
         @Valid @RequestBody req: StartChatSessionRequest,
     ): ResponseEntity<ChatSessionResponse> {
         val userUuid = UUID.fromString(userId)
-        val sessionId = ChatSessionId.random()
+        val conversationId = ConversationId.random()
         commandBus.dispatch(
-            StartChatSessionCommand(
-                sessionId = sessionId,
+            StartConversationCommand(
+                conversationId = conversationId,
                 userId = userUuid,
                 title = req.title,
-                kind = req.kind ?: ChatSessionKind.PLAIN,
+                kind = req.kind ?: ConversationKind.PLAIN,
             ),
         )
         val detail =
-            chatSessionQuery.get(sessionId)
+            conversationQuery.get(conversationId, userUuid)
                 ?: error("chat session not visible immediately after create")
-        return ResponseEntity.status(HttpStatus.CREATED).body(ChatSessionResponse.of(detail.session))
+        return ResponseEntity.status(HttpStatus.CREATED).body(ChatSessionResponse.of(detail.conversation))
     }
 
     @GetMapping
+    @Deprecated("Use GET /api/v1/conversations.")
     fun list(
         @RequestHeader("X-User-Id") userId: String,
     ): List<ChatSessionResponse> =
-        chatSessionQuery
+        conversationQuery
             .list(UUID.fromString(userId))
             .map(ChatSessionResponse::of)
 
+    // These two predate #80 and carried no identity, so declaring the header
+    // required would break their published contract. Absent or unparseable
+    // identity refuses exactly like a wrong one: 404, never a hint.
+    private fun callerId(userId: String?): UUID? =
+        userId?.takeIf { it.isNotBlank() }?.let { runCatching { UUID.fromString(it) }.getOrNull() }
+
     @GetMapping("/{id}")
+    @Deprecated("Use GET /api/v1/conversations/{id}, which returns a typed ConversationDetailResponse.")
     fun get(
         @PathVariable id: UUID,
+        @RequestHeader("X-User-Id", required = false) userId: String?,
     ): ResponseEntity<Map<String, Any>> {
-        val detail = chatSessionQuery.get(ChatSessionId(id)) ?: return ResponseEntity.notFound().build()
+        val userUuid = callerId(userId) ?: return ResponseEntity.notFound().build()
+        val detail =
+            conversationQuery.get(ConversationId(id), userUuid)
+                ?: return ResponseEntity.notFound().build()
         return ResponseEntity.ok(
             mapOf(
-                "session" to ChatSessionResponse.of(detail.session),
+                "session" to ChatSessionResponse.of(detail.conversation),
                 "messages" to detail.messages.map(ChatMessageResponse::of),
             ),
         )
     }
 
     @PostMapping("/{id}/messages")
+    @Deprecated("Use POST /api/v1/conversations/{id}/messages.")
     fun appendMessage(
         @PathVariable id: UUID,
+        @RequestHeader("X-User-Id", required = false) userId: String?,
         @Valid @RequestBody req: AppendChatMessageRequest,
     ): ResponseEntity<ChatMessageResponse> {
-        val messageId = ChatMessageId.random()
+        val conversationId = ConversationId(id)
+        // Resolve the caller and their ownership in one step, before anything
+        // is dispatched: the alias delegates to ConversationQueryService so it
+        // inherits the check rather than reimplementing it (see #80).
+        val userUuid =
+            callerId(userId)?.takeIf { conversationQuery.get(conversationId, it) != null }
+                ?: return ResponseEntity.notFound().build()
+        val messageId = ConversationMessageId.random()
         commandBus.dispatch(
-            AppendChatMessageCommand(
+            AppendConversationMessageCommand(
                 messageId = messageId,
-                sessionId = ChatSessionId(id),
+                conversationId = conversationId,
                 role = req.role,
                 body = req.body,
             ),
         )
-        val detail = chatSessionQuery.get(ChatSessionId(id)) ?: return ResponseEntity.notFound().build()
+        val detail = conversationQuery.get(conversationId, userUuid) ?: return ResponseEntity.notFound().build()
         val message =
             detail.messages.firstOrNull { it.id == messageId }
                 ?: error("message not visible immediately after append")
         return ResponseEntity.status(HttpStatus.CREATED).body(ChatMessageResponse.of(message))
     }
 
-    // Excluded from the OpenAPI contract: an SSE/text-event-stream
-    // endpoint cannot be modelled usefully by openapi-typescript, and the
-    // UI consumes it through a hand-written fetch + ReadableStream reader
-    // rather than the generated client. Keeping it out of the spec leaves
-    // the generated types in sync without a degenerate stream type.
+    // Excluded from the OpenAPI contract for the same reason as the
+    // canonical controller's stream endpoint (see there); this alias
+    // exists purely so an in-flight stream connection from an old
+    // client keeps working.
     @Hidden
     @PostMapping("/{id}/messages/stream")
     fun streamMessage(
         @PathVariable id: UUID,
+        @RequestHeader("X-User-Id") userId: String,
         @Valid @RequestBody req: AppendChatMessageRequest,
     ): ResponseEntity<SseEmitter> {
-        val emitter = chatAnswerStream.stream(ChatSessionId(id), req.body)
+        val conversationId = ConversationId(id)
+        conversationQuery.get(conversationId, UUID.fromString(userId)) ?: return ResponseEntity.notFound().build()
+        val emitter = chatAnswerStream.stream(conversationId, req.body)
         return ResponseEntity
             .ok()
             .contentType(MediaType.TEXT_EVENT_STREAM)
@@ -120,13 +150,14 @@ class ChatSessionController(
     }
 
     @DeleteMapping("/{id}")
+    @Deprecated("Use DELETE /api/v1/conversations/{id}.")
     fun archive(
         @PathVariable id: UUID,
         @RequestHeader("X-User-Id") userId: String,
     ): ResponseEntity<Unit> {
         commandBus.dispatch(
-            ArchiveChatSessionCommand(
-                sessionId = ChatSessionId(id),
+            ArchiveConversationCommand(
+                conversationId = ConversationId(id),
                 userId = UUID.fromString(userId),
             ),
         )
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/ConversationController.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/ConversationController.kt
new file mode 100644
index 0000000..f877b91
--- /dev/null
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/ConversationController.kt
@@ -0,0 +1,170 @@
+package com.jorisjonkers.personalstack.agents.infrastructure.web
+
+import com.jorisjonkers.personalstack.agents.application.chat.ChatAnswerStreamService
+import com.jorisjonkers.personalstack.agents.application.command.AppendConversationMessageCommand
+import com.jorisjonkers.personalstack.agents.application.command.ArchiveConversationCommand
+import com.jorisjonkers.personalstack.agents.application.command.StartConversationCommand
+import com.jorisjonkers.personalstack.agents.application.query.ConversationQueryService
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationKind
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageId
+import com.jorisjonkers.personalstack.agents.infrastructure.web.dto.AppendConversationMessageRequest
+import com.jorisjonkers.personalstack.agents.infrastructure.web.dto.ConversationDetailResponse
+import com.jorisjonkers.personalstack.agents.infrastructure.web.dto.ConversationMessageResponse
+import com.jorisjonkers.personalstack.agents.infrastructure.web.dto.ConversationResponse
+import com.jorisjonkers.personalstack.agents.infrastructure.web.dto.StartConversationRequest
+import com.jorisjonkers.personalstack.common.command.CommandBus
+import io.swagger.v3.oas.annotations.Hidden
+import io.swagger.v3.oas.annotations.responses.ApiResponse
+import jakarta.validation.Valid
+import org.springframework.http.HttpStatus
+import org.springframework.http.MediaType
+import org.springframework.http.ResponseEntity
+import org.springframework.web.bind.annotation.DeleteMapping
+import org.springframework.web.bind.annotation.GetMapping
+import org.springframework.web.bind.annotation.PathVariable
+import org.springframework.web.bind.annotation.PostMapping
+import org.springframework.web.bind.annotation.RequestBody
+import org.springframework.web.bind.annotation.RequestHeader
+import org.springframework.web.bind.annotation.RequestMapping
+import org.springframework.web.bind.annotation.RestController
+import org.springframework.web.servlet.mvc.method.annotation.SseEmitter
+import java.util.UUID
+
+@RestController
+@RequestMapping("/api/v1/conversations")
+class ConversationController(
+    private val commandBus: CommandBus,
+    private val conversationQuery: ConversationQueryService,
+    private val chatAnswerStream: ChatAnswerStreamService,
+) {
+    @PostMapping
+    // springdoc can't infer the status from a dynamically built
+    // ResponseEntity; document the real 201 so the spec is truthful.
+    @ApiResponse(responseCode = "201", description = "Created")
+    fun create(
+        @RequestHeader("X-User-Id") userId: String,
+        @Valid @RequestBody req: StartConversationRequest,
+    ): ResponseEntity<ConversationResponse> {
+        val userUuid = UUID.fromString(userId)
+        val conversationId = ConversationId.random()
+        commandBus.dispatch(
+            StartConversationCommand(
+                conversationId = conversationId,
+                userId = userUuid,
+                title = req.title,
+                kind = req.kind ?: ConversationKind.PLAIN,
+            ),
+        )
+        val detail =
+            conversationQuery.get(conversationId, userUuid)
+                ?: error("conversation not visible immediately after create")
+        return ResponseEntity.status(HttpStatus.CREATED).body(ConversationResponse.of(detail.conversation))
+    }
+
+    @GetMapping
+    fun list(
+        @RequestHeader("X-User-Id") userId: String,
+    ): List<ConversationResponse> =
+        conversationQuery
+            .list(UUID.fromString(userId))
+            .map(ConversationResponse::of)
+
+    @GetMapping("/{id}")
+    fun get(
+        @PathVariable id: UUID,
+        @RequestHeader("X-User-Id") userId: String,
+    ): ResponseEntity<ConversationDetailResponse> {
+        val detail =
+            conversationQuery.get(ConversationId(id), UUID.fromString(userId))
+                ?: return ResponseEntity.notFound().build()
+        return ResponseEntity.ok(ConversationDetailResponse.of(detail.conversation, detail.messages))
+    }
+
+    // Restores the legacy /api/v1/conversations/{conversationId}/messages
+    // list endpoint, serving the renamed model. Ownership is enforced
+    // through the same seam as GET /{id} (see #80): an unowned
+    // conversation reads as 404, not an empty list.
+    @GetMapping("/{id}/messages")
+    fun listMessages(
+        @PathVariable id: UUID,
+        @RequestHeader("X-User-Id") userId: String,
+    ): ResponseEntity<List<ConversationMessageResponse>> {
+        val detail =
+            conversationQuery.get(ConversationId(id), UUID.fromString(userId))
+                ?: return ResponseEntity.notFound().build()
+        return ResponseEntity.ok(detail.messages.map(ConversationMessageResponse::of))
+    }
+
+    @PostMapping("/{id}/messages")
+    // springdoc can't infer the status from a dynamically built
+    // ResponseEntity; document the real 201 so the spec is truthful.
+    @ApiResponse(responseCode = "201", description = "Created")
+    fun appendMessage(
+        @PathVariable id: UUID,
+        @RequestHeader("X-User-Id") userId: String,
+        @Valid @RequestBody req: AppendConversationMessageRequest,
+    ): ResponseEntity<ConversationMessageResponse> {
+        val userUuid = UUID.fromString(userId)
+        val conversationId = ConversationId(id)
+        // Ownership is resolved before dispatch, so a refused request has
+        // no side effect (see #80).
+        conversationQuery.get(conversationId, userUuid) ?: return ResponseEntity.notFound().build()
+        val messageId = ConversationMessageId.random()
+        commandBus.dispatch(
+            AppendConversationMessageCommand(
+                messageId = messageId,
+                conversationId = conversationId,
+                role = req.resolvedRole(),
+                body = req.resolvedBody(),
+            ),
+        )
+        val detail = conversationQuery.get(conversationId, userUuid) ?: return ResponseEntity.notFound().build()
+        val message =
+            detail.messages.firstOrNull { it.id == messageId }
+                ?: error("message not visible immediately after append")
+        return ResponseEntity.status(HttpStatus.CREATED).body(ConversationMessageResponse.of(message))
+    }
+
+    // Excluded from the OpenAPI contract: an SSE/text-event-stream
+    // endpoint cannot be modelled usefully by openapi-typescript, and the
+    // UI consumes it through a hand-written fetch + ReadableStream reader
+    // rather than the generated client. Keeping it out of the spec leaves
+    // the generated types in sync without a degenerate stream type.
+    @Hidden
+    @PostMapping("/{id}/messages/stream")
+    fun streamMessage(
+        @PathVariable id: UUID,
+        @RequestHeader("X-User-Id") userId: String,
+        @Valid @RequestBody req: AppendConversationMessageRequest,
+    ): ResponseEntity<SseEmitter> {
+        val conversationId = ConversationId(id)
+        // Ownership is resolved before streaming starts, so a refused
+        // request never drives generation or token spend (see #80).
+        conversationQuery.get(conversationId, UUID.fromString(userId)) ?: return ResponseEntity.notFound().build()
+        val emitter = chatAnswerStream.stream(conversationId, req.resolvedBody())
+        return ResponseEntity
+            .ok()
+            .contentType(MediaType.TEXT_EVENT_STREAM)
+            .header("Cache-Control", "no-cache")
+            .header("X-Accel-Buffering", "no")
+            .body(emitter)
+    }
+
+    @DeleteMapping("/{id}")
+    // springdoc can't infer the status from a dynamically built
+    // ResponseEntity; document the real 204 so the spec is truthful.
+    @ApiResponse(responseCode = "204", description = "No Content")
+    fun archive(
+        @PathVariable id: UUID,
+        @RequestHeader("X-User-Id") userId: String,
+    ): ResponseEntity<Unit> {
+        commandBus.dispatch(
+            ArchiveConversationCommand(
+                conversationId = ConversationId(id),
+                userId = UUID.fromString(userId),
+            ),
+        )
+        return ResponseEntity.noContent().build()
+    }
+}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/dto/ChatSessionAliasDtos.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/dto/ChatSessionAliasDtos.kt
new file mode 100644
index 0000000..0bf51a2
--- /dev/null
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/dto/ChatSessionAliasDtos.kt
@@ -0,0 +1,68 @@
+package com.jorisjonkers.personalstack.agents.infrastructure.web.dto
+
+import com.jorisjonkers.personalstack.agents.domain.model.Conversation
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationKind
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessage
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageRole
+import jakarta.validation.constraints.NotBlank
+import jakarta.validation.constraints.Size
+import java.time.Instant
+import java.util.UUID
+
+// Wire-compat DTOs for the deprecated /api/v1/chat-sessions alias
+// (ChatSessionController). Kept separate from ConversationDtos so the
+// canonical shapes (ConversationMessageResponse.conversationId, the
+// typed ConversationDetailResponse) can change without moving this
+// surface, which agents-ui still depends on byte-for-byte.
+
+data class StartChatSessionRequest(
+    @field:Size(max = 120) val title: String? = null,
+    val kind: ConversationKind? = null,
+)
+
+data class ChatSessionResponse(
+    val id: UUID,
+    val userId: UUID,
+    val title: String?,
+    val status: String,
+    val kind: String,
+    val createdAt: Instant,
+    val updatedAt: Instant,
+) {
+    companion object {
+        fun of(c: Conversation) =
+            ChatSessionResponse(
+                id = c.id.value,
+                userId = c.userId,
+                title = c.title,
+                status = c.status.name,
+                kind = c.kind.name,
+                createdAt = c.createdAt,
+                updatedAt = c.updatedAt,
+            )
+    }
+}
+
+data class AppendChatMessageRequest(
+    @field:NotBlank val body: String,
+    val role: ConversationMessageRole = ConversationMessageRole.USER,
+)
+
+data class ChatMessageResponse(
+    val id: UUID,
+    val sessionId: UUID,
+    val role: String,
+    val body: String,
+    val createdAt: Instant,
+) {
+    companion object {
+        fun of(m: ConversationMessage) =
+            ChatMessageResponse(
+                id = m.id.value,
+                sessionId = m.conversationId.value,
+                role = m.role.name,
+                body = m.body,
+                createdAt = m.createdAt,
+            )
+    }
+}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/dto/ChatSessionDtos.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/dto/ChatSessionDtos.kt
deleted file mode 100644
index 3530cef..0000000
--- a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/dto/ChatSessionDtos.kt
+++ /dev/null
@@ -1,65 +0,0 @@
-package com.jorisjonkers.personalstack.agents.infrastructure.web.dto
-
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessage
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessageRole
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSession
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionKind
-import jakarta.validation.constraints.NotBlank
-import jakarta.validation.constraints.Size
-import java.time.Instant
-import java.util.UUID
-
-data class StartChatSessionRequest(
-    @field:Size(max = 120) val title: String? = null,
-    // Nullable so an absent field deserializes to null on any Jackson
-    // setup (a non-null Kotlin default is not honored for a missing
-    // property); the controller coalesces null to PLAIN.
-    val kind: ChatSessionKind? = null,
-)
-
-data class ChatSessionResponse(
-    val id: UUID,
-    val userId: UUID,
-    val title: String?,
-    val status: String,
-    val kind: String,
-    val createdAt: Instant,
-    val updatedAt: Instant,
-) {
-    companion object {
-        fun of(s: ChatSession) =
-            ChatSessionResponse(
-                id = s.id.value,
-                userId = s.userId,
-                title = s.title,
-                status = s.status.name,
-                kind = s.kind.name,
-                createdAt = s.createdAt,
-                updatedAt = s.updatedAt,
-            )
-    }
-}
-
-data class AppendChatMessageRequest(
-    @field:NotBlank val body: String,
-    val role: ChatMessageRole = ChatMessageRole.USER,
-)
-
-data class ChatMessageResponse(
-    val id: UUID,
-    val sessionId: UUID,
-    val role: String,
-    val body: String,
-    val createdAt: Instant,
-) {
-    companion object {
-        fun of(m: ChatMessage) =
-            ChatMessageResponse(
-                id = m.id.value,
-                sessionId = m.sessionId.value,
-                role = m.role.name,
-                body = m.body,
-                createdAt = m.createdAt,
-            )
-    }
-}
diff --git a/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/dto/ConversationDtos.kt b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/dto/ConversationDtos.kt
new file mode 100644
index 0000000..0e2bfec
--- /dev/null
+++ b/api/src/main/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/dto/ConversationDtos.kt
@@ -0,0 +1,109 @@
+package com.jorisjonkers.personalstack.agents.infrastructure.web.dto
+
+import com.jorisjonkers.personalstack.agents.domain.model.Conversation
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationKind
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessage
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageRole
+import jakarta.validation.constraints.Size
+import java.time.Instant
+import java.util.UUID
+
+data class StartConversationRequest(
+    @field:Size(max = 120) val title: String? = null,
+    // Nullable so an absent field deserializes to null on any Jackson
+    // setup (a non-null Kotlin default is not honored for a missing
+    // property); the controller coalesces null to PLAIN.
+    val kind: ConversationKind? = null,
+)
+
+data class ConversationResponse(
+    val id: UUID,
+    val userId: UUID,
+    val title: String?,
+    val status: String,
+    val kind: String,
+    val createdAt: Instant,
+    val updatedAt: Instant,
+) {
+    companion object {
+        fun of(c: Conversation) =
+            ConversationResponse(
+                id = c.id.value,
+                userId = c.userId,
+                title = c.title,
+                status = c.status.name,
+                kind = c.kind.name,
+                createdAt = c.createdAt,
+                updatedAt = c.updatedAt,
+            )
+    }
+}
+
+// body/content both nullable (rather than one @NotBlank field) so
+// either the canonical `body` or the legacy `content` name can be
+// absent without failing bean validation; resolvedBody() picks
+// whichever is present and the handler still rejects a blank result.
+data class AppendConversationMessageRequest(
+    val body: String? = null,
+    val content: String? = null,
+    val role: ConversationMessageRole? = null,
+) {
+    fun resolvedBody(): String = (body ?: content).orEmpty()
+
+    fun resolvedRole(): ConversationMessageRole = role ?: ConversationMessageRole.USER
+}
+
+data class ConversationMessageResponse(
+    val id: UUID,
+    val conversationId: UUID,
+    val role: String,
+    val body: String,
+    // Wire-compat: the legacy /api/v1/conversations response used
+    // `content`; duplicated alongside `body` so an old reader of the
+    // canonical path keeps working.
+    val content: String,
+    val createdAt: Instant,
+) {
+    companion object {
+        fun of(m: ConversationMessage) =
+            ConversationMessageResponse(
+                id = m.id.value,
+                conversationId = m.conversationId.value,
+                role = m.role.name,
+                body = m.body,
+                content = m.body,
+                createdAt = m.createdAt,
+            )
+    }
+}
+
+// Flat shape restored to match the legacy /api/v1/conversations/{id}
+// response (id/userId/title/status/createdAt/updatedAt at top level);
+// only `kind` and `messages` are additions. The deprecated
+// /api/v1/chat-sessions alias keeps its own untyped map instead.
+data class ConversationDetailResponse(
+    val id: UUID,
+    val userId: UUID,
+    val title: String?,
+    val status: String,
+    val kind: String,
+    val createdAt: Instant,
+    val updatedAt: Instant,
+    val messages: List<ConversationMessageResponse>,
+) {
+    companion object {
+        fun of(
+            conversation: Conversation,
+            messages: List<ConversationMessage>,
+        ) = ConversationDetailResponse(
+            id = conversation.id.value,
+            userId = conversation.userId,
+            title = conversation.title,
+            status = conversation.status.name,
+            kind = conversation.kind.name,
+            createdAt = conversation.createdAt,
+            updatedAt = conversation.updatedAt,
+            messages = messages.map(ConversationMessageResponse::of),
+        )
+    }
+}
diff --git a/api/src/main/resources/db/migration/V27__rename_chat_sessions_to_conversations.sql b/api/src/main/resources/db/migration/V27__rename_chat_sessions_to_conversations.sql
new file mode 100644
index 0000000..4936757
--- /dev/null
+++ b/api/src/main/resources/db/migration/V27__rename_chat_sessions_to_conversations.sql
@@ -0,0 +1,8 @@
+-- The no-Pod chat surface takes over the `Conversation` name now that
+-- the legacy model is gone (V26). RENAME preserves every row -- the
+-- point of doing this in-place rather than as a drop/recreate is that
+-- existing chats remain available afterwards, just addressed through
+-- the new name.
+ALTER TABLE chat_sessions RENAME TO conversations;
+ALTER TABLE chat_session_messages RENAME TO conversation_messages;
+ALTER TABLE conversation_messages RENAME COLUMN chat_session_id TO conversation_id;
diff --git a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/chat/ChatAnswerStreamServiceTest.kt b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/chat/ChatAnswerStreamServiceTest.kt
index df40892..704a5b6 100644
--- a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/chat/ChatAnswerStreamServiceTest.kt
+++ b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/chat/ChatAnswerStreamServiceTest.kt
@@ -1,16 +1,16 @@
 package com.jorisjonkers.personalstack.agents.application.chat
 
-import com.jorisjonkers.personalstack.agents.application.command.AppendChatMessageCommand
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessage
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessageId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessageRole
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSession
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionKind
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionStatus
+import com.jorisjonkers.personalstack.agents.application.command.AppendConversationMessageCommand
+import com.jorisjonkers.personalstack.agents.domain.model.Conversation
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationKind
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessage
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageRole
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationStatus
 import com.jorisjonkers.personalstack.agents.domain.port.ChatGenerationPort
-import com.jorisjonkers.personalstack.agents.domain.port.ChatMessageRepository
-import com.jorisjonkers.personalstack.agents.domain.port.ChatSessionRepository
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationMessageRepository
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationRepository
 import com.jorisjonkers.personalstack.common.command.CommandBus
 import io.mockk.every
 import io.mockk.just
@@ -24,19 +24,19 @@ import java.util.UUID
 import java.util.concurrent.Executor
 
 class ChatAnswerStreamServiceTest {
-    private val sessions = mockk<ChatSessionRepository>()
-    private val messages = mockk<ChatMessageRepository>()
+    private val conversations = mockk<ConversationRepository>()
+    private val messages = mockk<ConversationMessageRepository>()
     private val commandBus = mockk<CommandBus>()
     private val generation = mockk<ChatGenerationPort>()
     private val executor = Executor { it.run() }
-    private val service = ChatAnswerStreamService(sessions, messages, commandBus, generation, executor)
+    private val service = ChatAnswerStreamService(conversations, messages, commandBus, generation, executor)
 
     @Test
     fun `stream persists agent message when an answer is produced`() {
-        val session = session()
-        val commands = mutableListOf<AppendChatMessageCommand>()
-        every { sessions.findById(session.id) } returns session
-        every { messages.findAllBySessionIdOrderedByTime(session.id) } returns emptyList()
+        val conversation = conversation()
+        val commands = mutableListOf<AppendConversationMessageCommand>()
+        every { conversations.findById(conversation.id) } returns conversation
+        every { messages.findAllByConversationIdOrderedByTime(conversation.id) } returns emptyList()
         every { commandBus.dispatch(capture(commands)) } just runs
         every { generation.generate("Hi", any()) } answers {
             secondArg<(String) -> Unit>().invoke("Hel")
@@ -44,57 +44,57 @@ class ChatAnswerStreamServiceTest {
             "Hello"
         }
 
-        service.stream(session.id, "Hi")
+        service.stream(conversation.id, "Hi")
 
         assertThat(commands).hasSize(1)
-        assertThat(commands[0].sessionId).isEqualTo(session.id)
-        assertThat(commands[0].role).isEqualTo(ChatMessageRole.ASSISTANT)
+        assertThat(commands[0].conversationId).isEqualTo(conversation.id)
+        assertThat(commands[0].role).isEqualTo(ConversationMessageRole.ASSISTANT)
         assertThat(commands[0].body).isEqualTo("Hello")
     }
 
     @Test
     fun `stream persists no agent message when no answer is produced`() {
-        val session = session()
-        val commands = mutableListOf<AppendChatMessageCommand>()
-        every { sessions.findById(session.id) } returns session
-        every { messages.findAllBySessionIdOrderedByTime(session.id) } returns emptyList()
+        val conversation = conversation()
+        val commands = mutableListOf<AppendConversationMessageCommand>()
+        every { conversations.findById(conversation.id) } returns conversation
+        every { messages.findAllByConversationIdOrderedByTime(conversation.id) } returns emptyList()
         every { commandBus.dispatch(capture(commands)) } just runs
         every { generation.generate("Hi", any()) } returns ""
 
-        service.stream(session.id, "Hi")
+        service.stream(conversation.id, "Hi")
 
         assertThat(commands).isEmpty()
     }
 
     @Test
     fun `stream routes generation through ChatGenerationPort not LightRagClient`() {
-        val session = session()
+        val conversation = conversation()
         val promptSlot = slot<String>()
-        every { sessions.findById(session.id) } returns session
-        every { messages.findAllBySessionIdOrderedByTime(session.id) } returns emptyList()
+        every { conversations.findById(conversation.id) } returns conversation
+        every { messages.findAllByConversationIdOrderedByTime(conversation.id) } returns emptyList()
         every { commandBus.dispatch(any()) } just runs
         every { generation.generate(capture(promptSlot), any()) } returns "Answer"
 
-        service.stream(session.id, "Hello")
+        service.stream(conversation.id, "Hello")
 
         assertThat(promptSlot.captured).isEqualTo("Hello")
     }
 
     @Test
-    fun `prompt includes prior history turns when session has messages`() {
-        val session = session()
+    fun `prompt includes prior history turns when conversation has messages`() {
+        val conversation = conversation()
         val promptSlot = slot<String>()
         val history =
             listOf(
-                chatMessage(session.id, ChatMessageRole.USER, "What is Kotlin?"),
-                chatMessage(session.id, ChatMessageRole.ASSISTANT, "A JVM language."),
+                conversationMessage(conversation.id, ConversationMessageRole.USER, "What is Kotlin?"),
+                conversationMessage(conversation.id, ConversationMessageRole.ASSISTANT, "A JVM language."),
             )
-        every { sessions.findById(session.id) } returns session
-        every { messages.findAllBySessionIdOrderedByTime(session.id) } returns history
+        every { conversations.findById(conversation.id) } returns conversation
+        every { messages.findAllByConversationIdOrderedByTime(conversation.id) } returns history
         every { commandBus.dispatch(any()) } just runs
         every { generation.generate(capture(promptSlot), any()) } returns "Answer"
 
-        service.stream(session.id, "Tell me more")
+        service.stream(conversation.id, "Tell me more")
 
         assertThat(promptSlot.captured).contains("User: What is Kotlin?")
         assertThat(promptSlot.captured).contains("Assistant: A JVM language.")
@@ -103,32 +103,32 @@ class ChatAnswerStreamServiceTest {
 
     @Test
     fun `prompt with no history is just the user body`() {
-        val session = session()
+        val conversation = conversation()
         val promptSlot = slot<String>()
-        every { sessions.findById(session.id) } returns session
-        every { messages.findAllBySessionIdOrderedByTime(session.id) } returns emptyList()
+        every { conversations.findById(conversation.id) } returns conversation
+        every { messages.findAllByConversationIdOrderedByTime(conversation.id) } returns emptyList()
         every { commandBus.dispatch(any()) } just runs
         every { generation.generate(capture(promptSlot), any()) } returns "Answer"
 
-        service.stream(session.id, "Hello")
+        service.stream(conversation.id, "Hello")
 
         assertThat(promptSlot.captured).isEqualTo("Hello")
     }
 
     @Test
     fun `history is bounded to the most recent 20 messages`() {
-        val session = session()
+        val conversation = conversation()
         val promptSlot = slot<String>()
         val history =
             (1..25).map { i ->
-                chatMessage(session.id, ChatMessageRole.USER, "Message $i")
+                conversationMessage(conversation.id, ConversationMessageRole.USER, "Message $i")
             }
-        every { sessions.findById(session.id) } returns session
-        every { messages.findAllBySessionIdOrderedByTime(session.id) } returns history
+        every { conversations.findById(conversation.id) } returns conversation
+        every { messages.findAllByConversationIdOrderedByTime(conversation.id) } returns history
         every { commandBus.dispatch(any()) } just runs
         every { generation.generate(capture(promptSlot), any()) } returns "Answer"
 
-        service.stream(session.id, "Latest")
+        service.stream(conversation.id, "Latest")
 
         val captured = promptSlot.captured
         assertThat(captured).doesNotContain("User: Message 4\n")
@@ -140,20 +140,20 @@ class ChatAnswerStreamServiceTest {
 
     @Test
     fun `current user turn is not duplicated when already persisted in history`() {
-        val session = session()
+        val conversation = conversation()
         val promptSlot = slot<String>()
         val history =
             listOf(
-                chatMessage(session.id, ChatMessageRole.USER, "What is Kotlin?"),
-                chatMessage(session.id, ChatMessageRole.ASSISTANT, "A JVM language."),
-                chatMessage(session.id, ChatMessageRole.USER, "Tell me more"),
+                conversationMessage(conversation.id, ConversationMessageRole.USER, "What is Kotlin?"),
+                conversationMessage(conversation.id, ConversationMessageRole.ASSISTANT, "A JVM language."),
+                conversationMessage(conversation.id, ConversationMessageRole.USER, "Tell me more"),
             )
-        every { sessions.findById(session.id) } returns session
-        every { messages.findAllBySessionIdOrderedByTime(session.id) } returns history
+        every { conversations.findById(conversation.id) } returns conversation
+        every { messages.findAllByConversationIdOrderedByTime(conversation.id) } returns history
         every { commandBus.dispatch(any()) } just runs
         every { generation.generate(capture(promptSlot), any()) } returns "Answer"
 
-        service.stream(session.id, "Tell me more")
+        service.stream(conversation.id, "Tell me more")
 
         // History already ends with this exact user turn (persist-then-stream
         // ordering) so it must appear once, not twice.
@@ -163,32 +163,32 @@ class ChatAnswerStreamServiceTest {
 
     @Test
     fun `error during generation emits error SSE event`() {
-        val session = session()
-        every { sessions.findById(session.id) } returns session
-        every { messages.findAllBySessionIdOrderedByTime(session.id) } returns emptyList()
+        val conversation = conversation()
+        every { conversations.findById(conversation.id) } returns conversation
+        every { messages.findAllByConversationIdOrderedByTime(conversation.id) } returns emptyList()
         every { generation.generate(any(), any()) } throws RuntimeException("backend unavailable")
 
-        val emitter = service.stream(session.id, "Hi")
+        val emitter = service.stream(conversation.id, "Hi")
 
         assertThat(emitter).isNotNull()
     }
 
-    private fun session(
-        id: ChatSessionId = ChatSessionId.random(),
+    private fun conversation(
+        id: ConversationId = ConversationId.random(),
         userId: UUID = UUID.randomUUID(),
-    ): ChatSession {
+    ): Conversation {
         val now = Instant.now()
-        return ChatSession(id, userId, "x", ChatSessionStatus.ACTIVE, ChatSessionKind.PLAIN, now, now)
+        return Conversation(id, userId, "x", ConversationStatus.ACTIVE, ConversationKind.PLAIN, now, now)
     }
 
-    private fun chatMessage(
-        sessionId: ChatSessionId,
-        role: ChatMessageRole,
+    private fun conversationMessage(
+        conversationId: ConversationId,
+        role: ConversationMessageRole,
         body: String,
-    ): ChatMessage =
-        ChatMessage(
-            id = ChatMessageId.random(),
-            sessionId = sessionId,
+    ): ConversationMessage =
+        ConversationMessage(
+            id = ConversationMessageId.random(),
+            conversationId = conversationId,
             role = role,
             body = body,
             createdAt = Instant.now(),
diff --git a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendChatMessageCommandHandlerTest.kt b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendChatMessageCommandHandlerTest.kt
deleted file mode 100644
index f479b21..0000000
--- a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendChatMessageCommandHandlerTest.kt
+++ /dev/null
@@ -1,77 +0,0 @@
-package com.jorisjonkers.personalstack.agents.application.command
-
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessage
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessageId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatMessageRole
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSession
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionKind
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionStatus
-import com.jorisjonkers.personalstack.agents.domain.port.ChatMessageRepository
-import com.jorisjonkers.personalstack.agents.domain.port.ChatSessionRepository
-import com.jorisjonkers.personalstack.common.exception.NotFoundException
-import io.mockk.every
-import io.mockk.mockk
-import io.mockk.slot
-import io.mockk.verify
-import org.assertj.core.api.Assertions.assertThat
-import org.junit.jupiter.api.Test
-import org.junit.jupiter.api.assertThrows
-import java.time.Instant
-import java.util.UUID
-
-class AppendChatMessageCommandHandlerTest {
-    private val sessions = mockk<ChatSessionRepository>()
-    private val messages = mockk<ChatMessageRepository>()
-    private val handler = AppendChatMessageCommandHandler(sessions, messages)
-
-    private val session =
-        ChatSession(
-            id = ChatSessionId.random(),
-            userId = UUID.randomUUID(),
-            title = "x",
-            status = ChatSessionStatus.ACTIVE,
-            kind = ChatSessionKind.PLAIN,
-            createdAt = Instant.now(),
-            updatedAt = Instant.now(),
-        )
-
-    @Test
-    fun `handle persists the message and bumps session updatedAt`() {
-        every { sessions.findById(session.id) } returns session
-        val saved = slot<ChatMessage>()
-        every { messages.save(capture(saved)) } answers { saved.captured }
-        every { sessions.save(any()) } answers { firstArg() }
-
-        val mid = ChatMessageId.random()
-        handler.handle(AppendChatMessageCommand(mid, session.id, ChatMessageRole.USER, "Hello"))
-
-        assertThat(saved.captured.id).isEqualTo(mid)
-        assertThat(saved.captured.role).isEqualTo(ChatMessageRole.USER)
-        assertThat(saved.captured.body).isEqualTo("Hello")
-        verify { sessions.save(any()) }
-    }
-
-    @Test
-    fun `handle rejects a blank body`() {
-        every { sessions.findById(session.id) } returns session
-        assertThrows<IllegalArgumentException> {
-            handler.handle(AppendChatMessageCommand(ChatMessageId.random(), session.id, ChatMessageRole.USER, "  "))
-        }
-    }
-
-    @Test
-    fun `handle throws NotFound for an unknown session`() {
-        every { sessions.findById(any()) } returns null
-        assertThrows<NotFoundException> {
-            handler.handle(
-                AppendChatMessageCommand(
-                    messageId = ChatMessageId.random(),
-                    sessionId = ChatSessionId.random(),
-                    role = ChatMessageRole.USER,
-                    body = "hey",
-                ),
-            )
-        }
-    }
-}
diff --git a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendConversationMessageCommandHandlerTest.kt b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendConversationMessageCommandHandlerTest.kt
new file mode 100644
index 0000000..21ecd8a
--- /dev/null
+++ b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/AppendConversationMessageCommandHandlerTest.kt
@@ -0,0 +1,84 @@
+package com.jorisjonkers.personalstack.agents.application.command
+
+import com.jorisjonkers.personalstack.agents.domain.model.Conversation
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationKind
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessage
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageRole
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationStatus
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationMessageRepository
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationRepository
+import com.jorisjonkers.personalstack.common.exception.NotFoundException
+import io.mockk.every
+import io.mockk.mockk
+import io.mockk.slot
+import io.mockk.verify
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.assertThrows
+import java.time.Instant
+import java.util.UUID
+
+class AppendConversationMessageCommandHandlerTest {
+    private val conversations = mockk<ConversationRepository>()
+    private val messages = mockk<ConversationMessageRepository>()
+    private val handler = AppendConversationMessageCommandHandler(conversations, messages)
+
+    private val conversation =
+        Conversation(
+            id = ConversationId.random(),
+            userId = UUID.randomUUID(),
+            title = "x",
+            status = ConversationStatus.ACTIVE,
+            kind = ConversationKind.PLAIN,
+            createdAt = Instant.now(),
+            updatedAt = Instant.now(),
+        )
+
+    @Test
+    fun `handle persists the message and bumps conversation updatedAt`() {
+        every { conversations.findById(conversation.id) } returns conversation
+        val saved = slot<ConversationMessage>()
+        every { messages.save(capture(saved)) } answers { saved.captured }
+        every { conversations.save(any()) } answers { firstArg() }
+
+        val mid = ConversationMessageId.random()
+        handler.handle(AppendConversationMessageCommand(mid, conversation.id, ConversationMessageRole.USER, "Hello"))
+
+        assertThat(saved.captured.id).isEqualTo(mid)
+        assertThat(saved.captured.role).isEqualTo(ConversationMessageRole.USER)
+        assertThat(saved.captured.body).isEqualTo("Hello")
+        verify { conversations.save(any()) }
+    }
+
+    @Test
+    fun `handle rejects a blank body`() {
+        every { conversations.findById(conversation.id) } returns conversation
+        assertThrows<IllegalArgumentException> {
+            handler.handle(
+                AppendConversationMessageCommand(
+                    ConversationMessageId.random(),
+                    conversation.id,
+                    ConversationMessageRole.USER,
+                    "  ",
+                ),
+            )
+        }
+    }
+
+    @Test
+    fun `handle throws NotFound for an unknown conversation`() {
+        every { conversations.findById(any()) } returns null
+        assertThrows<NotFoundException> {
+            handler.handle(
+                AppendConversationMessageCommand(
+                    messageId = ConversationMessageId.random(),
+                    conversationId = ConversationId.random(),
+                    role = ConversationMessageRole.USER,
+                    body = "hey",
+                ),
+            )
+        }
+    }
+}
diff --git a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveChatSessionCommandHandlerTest.kt b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveChatSessionCommandHandlerTest.kt
deleted file mode 100644
index 7a0fa25..0000000
--- a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveChatSessionCommandHandlerTest.kt
+++ /dev/null
@@ -1,65 +0,0 @@
-package com.jorisjonkers.personalstack.agents.application.command
-
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSession
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionKind
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionStatus
-import com.jorisjonkers.personalstack.agents.domain.port.ChatSessionRepository
-import com.jorisjonkers.personalstack.common.exception.DomainException
-import com.jorisjonkers.personalstack.common.exception.NotFoundException
-import io.mockk.every
-import io.mockk.mockk
-import io.mockk.slot
-import io.mockk.verify
-import org.assertj.core.api.Assertions.assertThat
-import org.junit.jupiter.api.Test
-import org.junit.jupiter.api.assertThrows
-import java.time.Instant
-import java.util.UUID
-
-class ArchiveChatSessionCommandHandlerTest {
-    private val sessions = mockk<ChatSessionRepository>()
-    private val handler = ArchiveChatSessionCommandHandler(sessions)
-
-    private fun session(userId: UUID) =
-        ChatSession(
-            id = ChatSessionId.random(),
-            userId = userId,
-            title = "x",
-            status = ChatSessionStatus.ACTIVE,
-            kind = ChatSessionKind.PLAIN,
-            createdAt = Instant.now(),
-            updatedAt = Instant.now(),
-        )
-
-    @Test
-    fun `handle archives the session when the owner asks`() {
-        val uid = UUID.randomUUID()
-        val s = session(uid)
-        every { sessions.findById(s.id) } returns s
-        val saved = slot<ChatSession>()
-        every { sessions.save(capture(saved)) } answers { saved.captured }
-
-        handler.handle(ArchiveChatSessionCommand(s.id, uid))
-
-        assertThat(saved.captured.status).isEqualTo(ChatSessionStatus.ARCHIVED)
-        verify { sessions.save(any()) }
-    }
-
-    @Test
-    fun `handle throws NotFound for an unknown session`() {
-        every { sessions.findById(any()) } returns null
-        assertThrows<NotFoundException> {
-            handler.handle(ArchiveChatSessionCommand(ChatSessionId.random(), UUID.randomUUID()))
-        }
-    }
-
-    @Test
-    fun `handle rejects a non-owner`() {
-        val s = session(UUID.randomUUID())
-        every { sessions.findById(s.id) } returns s
-        assertThrows<DomainException> {
-            handler.handle(ArchiveChatSessionCommand(s.id, UUID.randomUUID()))
-        }
-    }
-}
diff --git a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveConversationCommandHandlerTest.kt b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveConversationCommandHandlerTest.kt
new file mode 100644
index 0000000..09f4952
--- /dev/null
+++ b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/ArchiveConversationCommandHandlerTest.kt
@@ -0,0 +1,65 @@
+package com.jorisjonkers.personalstack.agents.application.command
+
+import com.jorisjonkers.personalstack.agents.domain.model.Conversation
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationKind
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationStatus
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationRepository
+import com.jorisjonkers.personalstack.common.exception.DomainException
+import com.jorisjonkers.personalstack.common.exception.NotFoundException
+import io.mockk.every
+import io.mockk.mockk
+import io.mockk.slot
+import io.mockk.verify
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.assertThrows
+import java.time.Instant
+import java.util.UUID
+
+class ArchiveConversationCommandHandlerTest {
+    private val conversations = mockk<ConversationRepository>()
+    private val handler = ArchiveConversationCommandHandler(conversations)
+
+    private fun conversation(userId: UUID) =
+        Conversation(
+            id = ConversationId.random(),
+            userId = userId,
+            title = "x",
+            status = ConversationStatus.ACTIVE,
+            kind = ConversationKind.PLAIN,
+            createdAt = Instant.now(),
+            updatedAt = Instant.now(),
+        )
+
+    @Test
+    fun `handle archives the conversation when the owner asks`() {
+        val uid = UUID.randomUUID()
+        val c = conversation(uid)
+        every { conversations.findById(c.id) } returns c
+        val saved = slot<Conversation>()
+        every { conversations.save(capture(saved)) } answers { saved.captured }
+
+        handler.handle(ArchiveConversationCommand(c.id, uid))
+
+        assertThat(saved.captured.status).isEqualTo(ConversationStatus.ARCHIVED)
+        verify { conversations.save(any()) }
+    }
+
+    @Test
+    fun `handle throws NotFound for an unknown conversation`() {
+        every { conversations.findById(any()) } returns null
+        assertThrows<NotFoundException> {
+            handler.handle(ArchiveConversationCommand(ConversationId.random(), UUID.randomUUID()))
+        }
+    }
+
+    @Test
+    fun `handle rejects a non-owner`() {
+        val c = conversation(UUID.randomUUID())
+        every { conversations.findById(c.id) } returns c
+        assertThrows<DomainException> {
+            handler.handle(ArchiveConversationCommand(c.id, UUID.randomUUID()))
+        }
+    }
+}
diff --git a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/CreateWorkspaceCommandHandlerTest.kt b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/CreateWorkspaceCommandHandlerTest.kt
index 53acacd..3f65ad1 100644
--- a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/CreateWorkspaceCommandHandlerTest.kt
+++ b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/CreateWorkspaceCommandHandlerTest.kt
@@ -440,7 +440,7 @@ class CreateWorkspaceCommandHandlerTest {
     }
 
     @Test
-    fun `handle CHAT kind is rejected (chat lives in ChatSession)`() {
+    fun `handle CHAT kind is rejected (chat lives in Conversation)`() {
         assertThrows<IllegalArgumentException> {
             handler.handle(
                 CreateWorkspaceCommand(
diff --git a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartChatSessionCommandHandlerTest.kt b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartChatSessionCommandHandlerTest.kt
deleted file mode 100644
index 73a13e4..0000000
--- a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartChatSessionCommandHandlerTest.kt
+++ /dev/null
@@ -1,52 +0,0 @@
-package com.jorisjonkers.personalstack.agents.application.command
-
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSession
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionStatus
-import com.jorisjonkers.personalstack.agents.domain.port.ChatSessionRepository
-import io.mockk.every
-import io.mockk.mockk
-import io.mockk.slot
-import org.assertj.core.api.Assertions.assertThat
-import org.junit.jupiter.api.Test
-import java.util.UUID
-
-class StartChatSessionCommandHandlerTest {
-    private val sessions = mockk<ChatSessionRepository>()
-    private val handler = StartChatSessionCommandHandler(sessions)
-
-    @Test
-    fun `handle persists an ACTIVE session with trimmed title`() {
-        val saved = slot<ChatSession>()
-        every { sessions.save(capture(saved)) } answers { saved.captured }
-
-        val sid = ChatSessionId.random()
-        val uid = UUID.randomUUID()
-        handler.handle(StartChatSessionCommand(sid, uid, "  My chat  "))
-
-        assertThat(saved.captured.id).isEqualTo(sid)
-        assertThat(saved.captured.userId).isEqualTo(uid)
-        assertThat(saved.captured.title).isEqualTo("My chat")
-        assertThat(saved.captured.status).isEqualTo(ChatSessionStatus.ACTIVE)
-    }
-
-    @Test
-    fun `handle treats a blank title as null`() {
-        val saved = slot<ChatSession>()
-        every { sessions.save(capture(saved)) } answers { saved.captured }
-
-        handler.handle(StartChatSessionCommand(ChatSessionId.random(), UUID.randomUUID(), "   "))
-
-        assertThat(saved.captured.title).isNull()
-    }
-
-    @Test
-    fun `handle allows a null title`() {
-        val saved = slot<ChatSession>()
-        every { sessions.save(capture(saved)) } answers { saved.captured }
-
-        handler.handle(StartChatSessionCommand(ChatSessionId.random(), UUID.randomUUID(), null))
-
-        assertThat(saved.captured.title).isNull()
-    }
-}
diff --git a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartConversationCommandHandlerTest.kt b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartConversationCommandHandlerTest.kt
new file mode 100644
index 0000000..3ef7f7a
--- /dev/null
+++ b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/command/StartConversationCommandHandlerTest.kt
@@ -0,0 +1,52 @@
+package com.jorisjonkers.personalstack.agents.application.command
+
+import com.jorisjonkers.personalstack.agents.domain.model.Conversation
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationStatus
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationRepository
+import io.mockk.every
+import io.mockk.mockk
+import io.mockk.slot
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.Test
+import java.util.UUID
+
+class StartConversationCommandHandlerTest {
+    private val conversations = mockk<ConversationRepository>()
+    private val handler = StartConversationCommandHandler(conversations)
+
+    @Test
+    fun `handle persists an ACTIVE conversation with trimmed title`() {
+        val saved = slot<Conversation>()
+        every { conversations.save(capture(saved)) } answers { saved.captured }
+
+        val cid = ConversationId.random()
+        val uid = UUID.randomUUID()
+        handler.handle(StartConversationCommand(cid, uid, "  My chat  "))
+
+        assertThat(saved.captured.id).isEqualTo(cid)
+        assertThat(saved.captured.userId).isEqualTo(uid)
+        assertThat(saved.captured.title).isEqualTo("My chat")
+        assertThat(saved.captured.status).isEqualTo(ConversationStatus.ACTIVE)
+    }
+
+    @Test
+    fun `handle treats a blank title as null`() {
+        val saved = slot<Conversation>()
+        every { conversations.save(capture(saved)) } answers { saved.captured }
+
+        handler.handle(StartConversationCommand(ConversationId.random(), UUID.randomUUID(), "   "))
+
+        assertThat(saved.captured.title).isNull()
+    }
+
+    @Test
+    fun `handle allows a null title`() {
+        val saved = slot<Conversation>()
+        every { conversations.save(capture(saved)) } answers { saved.captured }
+
+        handler.handle(StartConversationCommand(ConversationId.random(), UUID.randomUUID(), null))
+
+        assertThat(saved.captured.title).isNull()
+    }
+}
diff --git a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/query/ConversationQueryServiceTest.kt b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/query/ConversationQueryServiceTest.kt
new file mode 100644
index 0000000..ebb2f9d
--- /dev/null
+++ b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/application/query/ConversationQueryServiceTest.kt
@@ -0,0 +1,91 @@
+package com.jorisjonkers.personalstack.agents.application.query
+
+import com.jorisjonkers.personalstack.agents.domain.model.Conversation
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationKind
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationStatus
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationMessageRepository
+import com.jorisjonkers.personalstack.agents.domain.port.ConversationRepository
+import io.mockk.every
+import io.mockk.mockk
+import io.mockk.verify
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.Test
+import java.time.Instant
+import java.util.UUID
+
+class ConversationQueryServiceTest {
+    private val conversations = mockk<ConversationRepository>()
+    private val messages = mockk<ConversationMessageRepository>()
+    private val service = ConversationQueryService(conversations, messages)
+
+    private fun conversation(
+        id: ConversationId = ConversationId.random(),
+        userId: UUID = UUID.randomUUID(),
+    ): Conversation {
+        val now = Instant.now()
+        return Conversation(id, userId, "x", ConversationStatus.ACTIVE, ConversationKind.PLAIN, now, now)
+    }
+
+    @Test
+    fun `get returns the detail for the owner`() {
+        val c = conversation()
+        every { conversations.findById(c.id) } returns c
+        every { messages.findAllByConversationIdOrderedByTime(c.id) } returns emptyList()
+
+        val result = service.get(c.id, c.userId)
+
+        assertThat(result).isEqualTo(ConversationQueryService.ConversationDetail(c, emptyList()))
+    }
+
+    @Test
+    fun `get returns nothing for another user's conversation`() {
+        val c = conversation()
+        val otherUser = UUID.randomUUID()
+        every { conversations.findById(c.id) } returns c
+
+        val result = service.get(c.id, otherUser)
+
+        assertThat(result).isNull()
+        verify(exactly = 0) { messages.findAllByConversationIdOrderedByTime(any()) }
+    }
+
+    @Test
+    fun `get returns nothing for an unknown id`() {
+        val unknownId = ConversationId.random()
+        val requester = UUID.randomUUID()
+        every { conversations.findById(unknownId) } returns null
+
+        val result = service.get(unknownId, requester)
+
+        assertThat(result).isNull()
+        verify(exactly = 0) { messages.findAllByConversationIdOrderedByTime(any()) }
+    }
+
+    @Test
+    fun `another user's id and an unknown id are indistinguishable at the seam`() {
+        val c = conversation()
+        val otherUser = UUID.randomUUID()
+        val unknownId = ConversationId.random()
+        every { conversations.findById(c.id) } returns c
+        every { conversations.findById(unknownId) } returns null
+
+        val forAnotherUsersConversation = service.get(c.id, otherUser)
+        val forAnUnknownId = service.get(unknownId, otherUser)
+
+        assertThat(forAnotherUsersConversation).isNull()
+        assertThat(forAnUnknownId).isNull()
+        assertThat(forAnotherUsersConversation).isEqualTo(forAnUnknownId)
+    }
+
+    @Test
+    fun `list is unaffected and remains scoped to the requesting user`() {
+        val userId = UUID.randomUUID()
+        val owned = conversation(userId = userId)
+        every { conversations.findAllByUserId(userId) } returns listOf(owned)
+
+        val result = service.list(userId)
+
+        assertThat(result).containsExactly(owned)
+    }
+}
diff --git a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/archunit/ArchitectureTest.kt b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/archunit/ArchitectureTest.kt
index 0eb2c82..a8f3eb9 100644
--- a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/archunit/ArchitectureTest.kt
+++ b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/archunit/ArchitectureTest.kt
@@ -5,8 +5,13 @@ import com.tngtech.archunit.core.importer.ClassFileImporter
 import com.tngtech.archunit.core.importer.ImportOption
 import com.tngtech.archunit.lang.syntax.ArchRuleDefinition.classes
 import com.tngtech.archunit.lang.syntax.ArchRuleDefinition.noClasses
+import org.assertj.core.api.Assertions.assertThat
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.TestInstance
+import org.springframework.web.bind.annotation.DeleteMapping
+import org.springframework.web.bind.annotation.GetMapping
+import org.springframework.web.bind.annotation.PostMapping
+import org.springframework.web.bind.annotation.RequestHeader
 
 @TestInstance(TestInstance.Lifecycle.PER_CLASS)
 class ArchitectureTest {
@@ -96,15 +101,14 @@ class ArchitectureTest {
         val redesignDomainTypes =
             com.tngtech.archunit.base.DescribedPredicate
                 .describe<com.tngtech.archunit.core.domain.JavaClass>(
-                    "redesign domain types (Repository*, ChatSession*, ChatMessage*, WorkspaceKind)",
+                    "redesign domain types (Repository*, Conversation*, WorkspaceKind)",
                 ) { javaClass ->
                     val inDomainModel = javaClass.packageName.endsWith(".domain.model")
                     val simpleName = javaClass.simpleName
                     inDomainModel &&
                         (
                             simpleName.startsWith("Repository") ||
-                                simpleName.startsWith("ChatSession") ||
-                                simpleName.startsWith("ChatMessage") ||
+                                simpleName.startsWith("Conversation") ||
                                 simpleName == "WorkspaceKind"
                         )
                 }
@@ -118,7 +122,7 @@ class ArchitectureTest {
                 "org.jooq..",
                 "com.fasterxml.jackson..",
             ).because(
-                "redesign domain entities (Repository / ChatSession / ChatMessage / " +
+                "redesign domain entities (Repository / Conversation / " +
                     "WorkspaceKind) must remain framework-free (ADR-006)",
             ).check(importedClasses)
     }
@@ -135,4 +139,35 @@ class ArchitectureTest {
             .because("query services must follow *QueryService naming convention")
             .check(importedClasses)
     }
+
+    @Test
+    fun `every Conversation handler requires the caller identity header`() {
+        val httpMappingAnnotations = listOf(GetMapping::class.java, PostMapping::class.java, DeleteMapping::class.java)
+        val handlerMethods =
+            importedClasses
+                .filter { it.simpleName == "ConversationController" || it.simpleName == "ChatSessionController" }
+                .flatMap { it.methods }
+                .filter { method -> httpMappingAnnotations.any(method::isAnnotatedWith) }
+
+        // The trap this guards against: a rename that leaves a name-based
+        // predicate matching zero classes, so the rule below would pass
+        // having checked nothing (see the CommandHandler-naming rule above
+        // and #80). Fail loudly instead of vacuously.
+        assertThat(handlerMethods)
+            .describedAs("expected to find Conversation/ChatSession handler methods to check")
+            .isNotEmpty()
+
+        val missingIdentityHeader =
+            handlerMethods.filterNot { method ->
+                method.reflect().parameters.any { parameter ->
+                    parameter.getAnnotation(RequestHeader::class.java)?.value == "X-User-Id"
+                }
+            }
+
+        assertThat(missingIdentityHeader)
+            .describedAs(
+                "handlers missing the X-User-Id header: %s",
+                missingIdentityHeader.map { it.fullName },
+            ).isEmpty()
+    }
 }
diff --git a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/ChatSessionControllerTest.kt b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/ChatSessionControllerTest.kt
index 295f616..97b34d2 100644
--- a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/ChatSessionControllerTest.kt
+++ b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/ChatSessionControllerTest.kt
@@ -2,11 +2,11 @@ package com.jorisjonkers.personalstack.agents.infrastructure.web
 
 import com.fasterxml.jackson.databind.ObjectMapper
 import com.jorisjonkers.personalstack.agents.application.chat.ChatAnswerStreamService
-import com.jorisjonkers.personalstack.agents.application.query.ChatSessionQueryService
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSession
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionId
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionKind
-import com.jorisjonkers.personalstack.agents.domain.model.ChatSessionStatus
+import com.jorisjonkers.personalstack.agents.application.query.ConversationQueryService
+import com.jorisjonkers.personalstack.agents.domain.model.Conversation
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationKind
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationStatus
 import com.jorisjonkers.personalstack.common.command.CommandBus
 import com.jorisjonkers.personalstack.common.web.GlobalExceptionHandler
 import io.mockk.every
@@ -29,9 +29,14 @@ import org.springframework.web.servlet.mvc.method.annotation.SseEmitter
 import java.time.Instant
 import java.util.UUID
 
+// This is the deprecated /api/v1/chat-sessions alias -- see
+// ConversationControllerTest for the canonical /api/v1/conversations
+// coverage. Kept to prove the alias still serves the pre-rename shapes
+// byte-for-byte, and inherits the same ownership check (see #80).
+@Suppress("DEPRECATION")
 class ChatSessionControllerTest {
     private val commandBus = mockk<CommandBus>(relaxed = true)
-    private val query = mockk<ChatSessionQueryService>()
+    private val query = mockk<ConversationQueryService>()
     private val chatAnswerStream = mockk<ChatAnswerStreamService>()
     private val objectMapper = ObjectMapper()
     private lateinit var mockMvc: MockMvc
@@ -46,22 +51,22 @@ class ChatSessionControllerTest {
                 .build()
     }
 
-    private fun session(
-        id: ChatSessionId = ChatSessionId.random(),
+    private fun conversation(
+        id: ConversationId = ConversationId.random(),
         userId: UUID = UUID.randomUUID(),
-    ): ChatSession {
+    ): Conversation {
         val now = Instant.now()
-        return ChatSession(id, userId, "x", ChatSessionStatus.ACTIVE, ChatSessionKind.PLAIN, now, now)
+        return Conversation(id, userId, "x", ConversationStatus.ACTIVE, ConversationKind.PLAIN, now, now)
     }
 
     @Test
     fun `POST creates session and returns 201`() {
-        val s = session()
-        every { query.get(any()) } returns ChatSessionQueryService.ChatSessionDetail(s, emptyList())
+        val c = conversation()
+        every { query.get(any(), c.userId) } returns ConversationQueryService.ConversationDetail(c, emptyList())
         mockMvc
             .perform(
                 post("/api/v1/chat-sessions")
-                    .header("X-User-Id", s.userId.toString())
+                    .header("X-User-Id", c.userId.toString())
                     .contentType(MediaType.APPLICATION_JSON)
                     .content(objectMapper.writeValueAsString(mapOf("title" to "x", "kind" to "PLAIN"))),
             ).andExpect(status().isCreated)
@@ -73,7 +78,7 @@ class ChatSessionControllerTest {
     @Test
     fun `GET list returns sessions for user`() {
         val uid = UUID.randomUUID()
-        every { query.list(uid) } returns listOf(session(userId = uid))
+        every { query.list(uid) } returns listOf(conversation(userId = uid))
         mockMvc
             .perform(get("/api/v1/chat-sessions").header("X-User-Id", uid.toString()))
             .andExpect(status().isOk)
@@ -81,37 +86,73 @@ class ChatSessionControllerTest {
     }
 
     @Test
-    fun `GET by id returns envelope`() {
-        val s = session()
-        every { query.get(s.id) } returns ChatSessionQueryService.ChatSessionDetail(s, emptyList())
+    fun `GET by id returns envelope for the owner`() {
+        val c = conversation()
+        every { query.get(c.id, c.userId) } returns ConversationQueryService.ConversationDetail(c, emptyList())
         mockMvc
-            .perform(get("/api/v1/chat-sessions/${s.id.value}"))
+            .perform(get("/api/v1/chat-sessions/${c.id.value}").header("X-User-Id", c.userId.toString()))
             .andExpect(status().isOk)
-            .andExpect(jsonPath("$.session.id").value(s.id.value.toString()))
+            .andExpect(jsonPath("$.session.id").value(c.id.value.toString()))
             .andExpect(jsonPath("$.messages").isArray)
     }
 
     @Test
-    fun `GET by id with unknown returns 404`() {
-        every { query.get(any()) } returns null
+    fun `GET by id with unknown session returns 404`() {
+        val requester = UUID.randomUUID()
+        every { query.get(any(), requester) } returns null
         mockMvc
-            .perform(get("/api/v1/chat-sessions/${UUID.randomUUID()}"))
+            .perform(get("/api/v1/chat-sessions/${UUID.randomUUID()}").header("X-User-Id", requester.toString()))
             .andExpect(status().isNotFound)
     }
 
     @Test
-    fun `POST messages dispatches the append command`() {
-        val s = session()
+    fun `GET by id owned by another user returns 404, indistinguishable from unknown`() {
+        val c = conversation()
+        val otherUser = UUID.randomUUID()
+        every { query.get(c.id, otherUser) } returns null
+        mockMvc
+            .perform(get("/api/v1/chat-sessions/${c.id.value}").header("X-User-Id", otherUser.toString()))
+            .andExpect(status().isNotFound)
+    }
+
+    // The header is declared optional so the alias keeps the contract it
+    // published before #80. That is only safe while its absence refuses
+    // exactly like a wrong identity does.
+    @Test
+    fun `GET by id without the identity header returns 404, never the conversation`() {
+        val c = conversation()
+        mockMvc
+            .perform(get("/api/v1/chat-sessions/${c.id.value}"))
+            .andExpect(status().isNotFound)
+        verify(exactly = 0) { query.get(any(), any()) }
+    }
+
+    @Test
+    fun `POST messages without the identity header returns 404 and appends no Turn`() {
+        val c = conversation()
+        mockMvc
+            .perform(
+                post("/api/v1/chat-sessions/${c.id.value}/messages")
+                    .contentType(MediaType.APPLICATION_JSON)
+                    .content(objectMapper.writeValueAsString(mapOf("body" to "hi", "role" to "USER"))),
+            ).andExpect(status().isNotFound)
+        verify(exactly = 0) { commandBus.dispatch(any()) }
+    }
+
+    @Test
+    fun `POST messages dispatches the append command for the owner`() {
+        val c = conversation()
         // The controller looks up the just-appended message by id after
         // dispatch. Return a detail with no matching message so the
         // controller takes the error path; the test asserts the
         // dispatch happened either way.
-        every { query.get(any<ChatSessionId>()) } returns
-            ChatSessionQueryService.ChatSessionDetail(s, emptyList())
+        every { query.get(c.id, c.userId) } returns
+            ConversationQueryService.ConversationDetail(c, emptyList())
         try {
             mockMvc
                 .perform(
-                    post("/api/v1/chat-sessions/${s.id.value}/messages")
+                    post("/api/v1/chat-sessions/${c.id.value}/messages")
+                        .header("X-User-Id", c.userId.toString())
                         .contentType(MediaType.APPLICATION_JSON)
                         .content(objectMapper.writeValueAsString(mapOf("body" to "hello", "role" to "USER"))),
                 )
@@ -124,13 +165,44 @@ class ChatSessionControllerTest {
     }
 
     @Test
-    fun `POST stream messages returns SSE response headers`() {
-        val s = session()
-        every { chatAnswerStream.stream(s.id, "hello") } returns SseEmitter()
+    fun `POST messages with unknown session returns 404 and appends no Turn`() {
+        val requester = UUID.randomUUID()
+        every { query.get(any(), requester) } returns null
+        mockMvc
+            .perform(
+                post("/api/v1/chat-sessions/${UUID.randomUUID()}/messages")
+                    .header("X-User-Id", requester.toString())
+                    .contentType(MediaType.APPLICATION_JSON)
+                    .content(objectMapper.writeValueAsString(mapOf("body" to "hello", "role" to "USER"))),
+            ).andExpect(status().isNotFound)
+        verify(exactly = 0) { commandBus.dispatch(any()) }
+    }
+
+    @Test
+    fun `POST messages owned by another user returns 404 and appends no Turn`() {
+        val c = conversation()
+        val otherUser = UUID.randomUUID()
+        every { query.get(c.id, otherUser) } returns null
+        mockMvc
+            .perform(
+                post("/api/v1/chat-sessions/${c.id.value}/messages")
+                    .header("X-User-Id", otherUser.toString())
+                    .contentType(MediaType.APPLICATION_JSON)
+                    .content(objectMapper.writeValueAsString(mapOf("body" to "hello", "role" to "USER"))),
+            ).andExpect(status().isNotFound)
+        verify(exactly = 0) { commandBus.dispatch(any()) }
+    }
+
+    @Test
+    fun `POST stream messages returns SSE response headers for the owner`() {
+        val c = conversation()
+        every { query.get(c.id, c.userId) } returns ConversationQueryService.ConversationDetail(c, emptyList())
+        every { chatAnswerStream.stream(c.id, "hello") } returns SseEmitter()
 
         mockMvc
             .perform(
-                post("/api/v1/chat-sessions/${s.id.value}/messages/stream")
+                post("/api/v1/chat-sessions/${c.id.value}/messages/stream")
+                    .header("X-User-Id", c.userId.toString())
                     .contentType(MediaType.APPLICATION_JSON)
                     .content(objectMapper.writeValueAsString(mapOf("body" to "hello", "role" to "USER"))),
             ).andExpect(status().isOk)
@@ -138,13 +210,17 @@ class ChatSessionControllerTest {
             .andExpect(content().contentTypeCompatibleWith(MediaType.TEXT_EVENT_STREAM))
             .andExpect(header().string("X-Accel-Buffering", "no"))
             .andExpect(header().string("Cache-Control", "no-cache"))
+
+        verify { chatAnswerStream.stream(c.id, "hello") }
     }
 
     @Test
     fun `POST stream messages with blank body returns validation error`() {
+        val requester = UUID.randomUUID()
         mockMvc
             .perform(
                 post("/api/v1/chat-sessions/${UUID.randomUUID()}/messages/stream")
+                    .header("X-User-Id", requester.toString())
                     .contentType(MediaType.APPLICATION_JSON)
                     .content(objectMapper.writeValueAsString(mapOf("body" to "", "role" to "USER"))),
             ).andExpect(status().isUnprocessableContent)
@@ -155,19 +231,38 @@ class ChatSessionControllerTest {
         mockMvc
             .perform(
                 post("/api/v1/chat-sessions/${UUID.randomUUID()}/messages/stream")
+                    .header("X-User-Id", UUID.randomUUID().toString())
                     .contentType(MediaType.APPLICATION_JSON),
             ).andExpect(status().isBadRequest)
     }
 
     @Test
-    fun `POST messages with unknown session returns 404`() {
-        every { query.get(any<ChatSessionId>()) } returns null
+    fun `POST stream messages with unknown session returns 404 and never starts a stream`() {
+        val requester = UUID.randomUUID()
+        every { query.get(any(), requester) } returns null
         mockMvc
             .perform(
-                post("/api/v1/chat-sessions/${UUID.randomUUID()}/messages")
+                post("/api/v1/chat-sessions/${UUID.randomUUID()}/messages/stream")
+                    .header("X-User-Id", requester.toString())
+                    .contentType(MediaType.APPLICATION_JSON)
+                    .content(objectMapper.writeValueAsString(mapOf("body" to "hello", "role" to "USER"))),
+            ).andExpect(status().isNotFound)
+        verify(exactly = 0) { chatAnswerStream.stream(any(), any()) }
+    }
+
+    @Test
+    fun `POST stream messages owned by another user returns 404 and never starts a stream`() {
+        val c = conversation()
+        val otherUser = UUID.randomUUID()
+        every { query.get(c.id, otherUser) } returns null
+        mockMvc
+            .perform(
+                post("/api/v1/chat-sessions/${c.id.value}/messages/stream")
+                    .header("X-User-Id", otherUser.toString())
                     .contentType(MediaType.APPLICATION_JSON)
                     .content(objectMapper.writeValueAsString(mapOf("body" to "hello", "role" to "USER"))),
             ).andExpect(status().isNotFound)
+        verify(exactly = 0) { chatAnswerStream.stream(any(), any()) }
     }
 
     @Test
diff --git a/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/ConversationControllerTest.kt b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/ConversationControllerTest.kt
new file mode 100644
index 0000000..21f7dae
--- /dev/null
+++ b/api/src/test/kotlin/com/jorisjonkers/personalstack/agents/infrastructure/web/ConversationControllerTest.kt
@@ -0,0 +1,271 @@
+package com.jorisjonkers.personalstack.agents.infrastructure.web
+
+import com.fasterxml.jackson.databind.ObjectMapper
+import com.jorisjonkers.personalstack.agents.application.chat.ChatAnswerStreamService
+import com.jorisjonkers.personalstack.agents.application.command.AppendConversationMessageCommand
+import com.jorisjonkers.personalstack.agents.application.query.ConversationQueryService
+import com.jorisjonkers.personalstack.agents.domain.model.Conversation
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationId
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationKind
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationMessageRole
+import com.jorisjonkers.personalstack.agents.domain.model.ConversationStatus
+import com.jorisjonkers.personalstack.common.command.Command
+import com.jorisjonkers.personalstack.common.command.CommandBus
+import com.jorisjonkers.personalstack.common.web.GlobalExceptionHandler
+import io.mockk.every
+import io.mockk.mockk
+import io.mockk.slot
+import io.mockk.verify
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.BeforeEach
+import org.junit.jupiter.api.Test
+import org.springframework.http.MediaType
+import org.springframework.test.web.servlet.MockMvc
+import org.springframework.test.web.servlet.request.MockMvcRequestBuilders.delete
+import org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get
+import org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post
+import org.springframework.test.web.servlet.result.MockMvcResultMatchers.content
+import org.springframework.test.web.servlet.result.MockMvcResultMatchers.header
+import org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath
+import org.springframework.test.web.servlet.result.MockMvcResultMatchers.request
+import org.springframework.test.web.servlet.result.MockMvcResultMatchers.status
+import org.springframework.test.web.servlet.setup.MockMvcBuilders
+import org.springframework.web.servlet.mvc.method.annotation.SseEmitter
+import java.time.Instant
+import java.util.UUID
+
+class ConversationControllerTest {
+    private val commandBus = mockk<CommandBus>(relaxed = true)
+    private val query = mockk<ConversationQueryService>()
+    private val chatAnswerStream = mockk<ChatAnswerStreamService>()
+    private val objectMapper = ObjectMapper()
+    private lateinit var mockMvc: MockMvc
+
+    @BeforeEach
+    fun setUp() {
+        val controller = ConversationController(commandBus, query, chatAnswerStream)
+        mockMvc =
+            MockMvcBuilders
+                .standaloneSetup(controller)
+                .setControllerAdvice(GlobalExceptionHandler())
+                .build()
+    }
+
+    private fun conversation(
+        id: ConversationId = ConversationId.random(),
+        userId: UUID = UUID.randomUUID(),
+    ): Conversation {
+        val now = Instant.now()
+        return Conversation(id, userId, "x", ConversationStatus.ACTIVE, ConversationKind.PLAIN, now, now)
+    }
+
+    @Test
+    fun `POST creates conversation and returns 201`() {
+        val c = conversation()
+        every { query.get(any(), c.userId) } returns ConversationQueryService.ConversationDetail(c, emptyList())
+        mockMvc
+            .perform(
+                post("/api/v1/conversations")
+                    .header("X-User-Id", c.userId.toString())
+                    .contentType(MediaType.APPLICATION_JSON)
+                    .content(objectMapper.writeValueAsString(mapOf("title" to "x", "kind" to "PLAIN"))),
+            ).andExpect(status().isCreated)
+            .andExpect(jsonPath("$.status").value("ACTIVE"))
+            .andExpect(jsonPath("$.kind").value("PLAIN"))
+        verify { commandBus.dispatch(any()) }
+    }
+
+    @Test
+    fun `GET list returns conversations for user`() {
+        val uid = UUID.randomUUID()
+        every { query.list(uid) } returns listOf(conversation(userId = uid))
+        mockMvc
+            .perform(get("/api/v1/conversations").header("X-User-Id", uid.toString()))
+            .andExpect(status().isOk)
+            .andExpect(jsonPath("$.length()").value(1))
+    }
+
+    @Test
+    fun `GET by id returns a flat ConversationDetailResponse for the owner`() {
+        val c = conversation()
+        every { query.get(c.id, c.userId) } returns ConversationQueryService.ConversationDetail(c, emptyList())
+        mockMvc
+            .perform(get("/api/v1/conversations/${c.id.value}").header("X-User-Id", c.userId.toString()))
+            .andExpect(status().isOk)
+            .andExpect(jsonPath("$.id").value(c.id.value.toString()))
+            .andExpect(jsonPath("$.title").value("x"))
+            .andExpect(jsonPath("$.messages").isArray)
+    }
+
+    @Test
+    fun `GET messages returns the conversation's messages for the owner`() {
+        val c = conversation()
+        every { query.get(c.id, c.userId) } returns ConversationQueryService.ConversationDetail(c, emptyList())
+        mockMvc
+            .perform(get("/api/v1/conversations/${c.id.value}/messages").header("X-User-Id", c.userId.toString()))
+            .andExpect(status().isOk)
+            .andExpect(jsonPath("$").isArray)
+    }
+
+    @Test
+    fun `GET messages owned by another user returns 404`() {
+        val c = conversation()
+        val otherUser = UUID.randomUUID()
+        every { query.get(c.id, otherUser) } returns null
+        mockMvc
+            .perform(get("/api/v1/conversations/${c.id.value}/messages").header("X-User-Id", otherUser.toString()))
+            .andExpect(status().isNotFound)
+    }
+
+    @Test
+    fun `GET by id with unknown conversation returns 404`() {
+        val requester = UUID.randomUUID()
+        every { query.get(any(), requester) } returns null
+        mockMvc
+            .perform(get("/api/v1/conversations/${UUID.randomUUID()}").header("X-User-Id", requester.toString()))
+            .andExpect(status().isNotFound)
+    }
+
+    @Test
+    fun `GET by id owned by another user returns 404, indistinguishable from unknown`() {
+        val c = conversation()
+        val otherUser = UUID.randomUUID()
+        every { query.get(c.id, otherUser) } returns null
+        mockMvc
+            .perform(get("/api/v1/conversations/${c.id.value}").header("X-User-Id", otherUser.toString()))
+            .andExpect(status().isNotFound)
+    }
+
+    @Test
+    fun `POST messages dispatches the append command for the owner`() {
+        val c = conversation()
+        every { query.get(c.id, c.userId) } returns
+            ConversationQueryService.ConversationDetail(c, emptyList())
+        try {
+            mockMvc
+                .perform(
+                    post("/api/v1/conversations/${c.id.value}/messages")
+                        .header("X-User-Id", c.userId.toString())
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(objectMapper.writeValueAsString(mapOf("body" to "hello", "role" to "USER"))),
+                )
+        } catch (_: Throwable) {
+            // The controller's error("message not visible…") surfaces
+            // as an unhandled exception in MockMvc; verify the
+            // dispatch happened regardless.
+        }
+        verify { commandBus.dispatch(any()) }
+    }
+
+    @Test
+    fun `POST messages accepts the legacy content field and defaults role to USER`() {
+        val c = conversation()
+        every { query.get(c.id, c.userId) } returns
+            ConversationQueryService.ConversationDetail(c, emptyList())
+        val dispatched = slot<Command>()
+        every { commandBus.dispatch(capture(dispatched)) } returns Unit
+        try {
+            mockMvc
+                .perform(
+                    post("/api/v1/conversations/${c.id.value}/messages")
+                        .header("X-User-Id", c.userId.toString())
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(objectMapper.writeValueAsString(mapOf("content" to "legacy hello"))),
+                )
+        } catch (_: Throwable) {
+            // Same unhandled-exception caveat as above.
+        }
+        val command = dispatched.captured as AppendConversationMessageCommand
+        assertThat(command.body).isEqualTo("legacy hello")
+        assertThat(command.role).isEqualTo(ConversationMessageRole.USER)
+    }
+
+    @Test
+    fun `POST messages with unknown conversation returns 404 and appends no Turn`() {
+        val requester = UUID.randomUUID()
+        every { query.get(any(), requester) } returns null
+        mockMvc
+            .perform(
+                post("/api/v1/conversations/${UUID.randomUUID()}/messages")
+                    .header("X-User-Id", requester.toString())
+                    .contentType(MediaType.APPLICATION_JSON)
+                    .content(objectMapper.writeValueAsString(mapOf("body" to "hello", "role" to "USER"))),
+            ).andExpect(status().isNotFound)
+        verify(exactly = 0) { commandBus.dispatch(any()) }
+    }
+
+    @Test
+    fun `POST messages owned by another user returns 404 and appends no Turn`() {
+        val c = conversation()
+        val otherUser = UUID.randomUUID()
+        every { query.get(c.id, otherUser) } returns null
+        mockMvc
+            .perform(
+                post("/api/v1/conversations/${c.id.value}/messages")
+                    .header("X-User-Id", otherUser.toString())
+                    .contentType(MediaType.APPLICATION_JSON)
+                    .content(objectMapper.writeValueAsString(mapOf("body" to "hello", "role" to "USER"))),
+            ).andExpect(status().isNotFound)
+        verify(exactly = 0) { commandBus.dispatch(any()) }
+    }
+
+    @Test
+    fun `POST messages stream starts for the owner`() {
+        val c = conversation()
+        every { query.get(c.id, c.userId) } returns ConversationQueryService.ConversationDetail(c, emptyList())
+        every { chatAnswerStream.stream(c.id, "hello") } returns SseEmitter()
+
+        mockMvc
+            .perform(
+                post("/api/v1/conversations/${c.id.value}/messages/stream")
+                    .header("X-User-Id", c.userId.toString())
+                    .contentType(MediaType.APPLICATION_JSON)
+                    .content(objectMapper.writeValueAsString(mapOf("body" to "hello", "role" to "USER"))),
+            ).andExpect(status().isOk)
+            .andExpect(request().asyncStarted())
+            .andExpect(content().contentTypeCompatibleWith(MediaType.TEXT_EVENT_STREAM))
+            .andExpect(header().string("Cache-Control", "no-cache"))
+            .andExpect(header().string("X-Accel-Buffering", "no"))
+
+        verify { chatAnswerStream.stream(c.id, "hello") }
+    }
+
+    @Test
+    fun `POST messages stream with unknown conversation returns 404 and never starts a stream`() {
+        val requester = UUID.randomUUID()
+        every { query.get(any(), requester) } returns null
+        mockMvc
+            .perform(
+                post("/api/v1/conversations/${UUID.randomUUID()}/messages/stream")
+                    .header("X-User-Id", requester.toString())
+                    .contentType(MediaType.APPLICATION_JSON)
+                    .content(objectMapper.writeValueAsString(mapOf("body" to "hello", "role" to "USER"))),
+            ).andExpect(status().isNotFound)
+        verify(exactly = 0) { chatAnswerStream.stream(any(), any()) }
+    }
+
+    @Test
+    fun `POST messages stream owned by another user returns 404 and never starts a stream`() {
+        val c = conversation()
+        val otherUser = UUID.randomUUID()
+        every { query.get(c.id, otherUser) } returns null
+        mockMvc
+            .perform(
+                post("/api/v1/conversations/${c.id.value}/messages/stream")
+                    .header("X-User-Id", otherUser.toString())
+                    .contentType(MediaType.APPLICATION_JSON)
+                    .content(objectMapper.writeValueAsString(mapOf("body" to "hello", "role" to "USER"))),
+            ).andExpect(status().isNotFound)
+        verify(exactly = 0) { chatAnswerStream.stream(any(), any()) }
+    }
+
+    @Test
+    fun `DELETE archives conversation and returns 204`() {
+        mockMvc
+            .perform(
+                delete("/api/v1/conversations/${UUID.randomUUID()}")
+                    .header("X-User-Id", UUID.randomUUID().toString()),
+            ).andExpect(status().isNoContent)
+        verify { commandBus.dispatch(any()) }
+    }
+}
diff --git a/client-spec/openapi/agents-api-client.json b/client-spec/openapi/agents-api-client.json
index f879361..25af4f9 100644
--- a/client-spec/openapi/agents-api-client.json
+++ b/client-spec/openapi/agents-api-client.json
@@ -689,10 +689,152 @@
         }
       }
     },
+    "/api/v1/conversations" : {
+      "get" : {
+        "tags" : [ "conversation-controller" ],
+        "operationId" : "list_3",
+        "parameters" : [ {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : true,
+          "schema" : {
+            "type" : "string"
+          }
+        } ],
+        "responses" : {
+          "200" : {
+            "description" : "OK",
+            "content" : {
+              "*/*" : {
+                "schema" : {
+                  "type" : "array",
+                  "items" : {
+                    "$ref" : "#/components/schemas/ConversationResponse"
+                  }
+                }
+              }
+            }
+          }
+        }
+      },
+      "post" : {
+        "tags" : [ "conversation-controller" ],
+        "operationId" : "create_3",
+        "parameters" : [ {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : true,
+          "schema" : {
+            "type" : "string"
+          }
+        } ],
+        "requestBody" : {
+          "content" : {
+            "application/json" : {
+              "schema" : {
+                "$ref" : "#/components/schemas/StartConversationRequest"
+              }
+            }
+          },
+          "required" : true
+        },
+        "responses" : {
+          "201" : {
+            "description" : "Created",
+            "content" : {
+              "*/*" : {
+                "schema" : {
+                  "$ref" : "#/components/schemas/ConversationResponse"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
+    "/api/v1/conversations/{id}/messages" : {
+      "get" : {
+        "tags" : [ "conversation-controller" ],
+        "operationId" : "listMessages",
+        "parameters" : [ {
+          "name" : "id",
+          "in" : "path",
+          "required" : true,
+          "schema" : {
+            "type" : "string",
+            "format" : "uuid"
+          }
+        }, {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : true,
+          "schema" : {
+            "type" : "string"
+          }
+        } ],
+        "responses" : {
+          "200" : {
+            "description" : "OK",
+            "content" : {
+              "*/*" : {
+                "schema" : {
+                  "type" : "array",
+                  "items" : {
+                    "$ref" : "#/components/schemas/ConversationMessageResponse"
+                  }
+                }
+              }
+            }
+          }
+        }
+      },
+      "post" : {
+        "tags" : [ "conversation-controller" ],
+        "operationId" : "appendMessage",
+        "parameters" : [ {
+          "name" : "id",
+          "in" : "path",
+          "required" : true,
+          "schema" : {
+            "type" : "string",
+            "format" : "uuid"
+          }
+        }, {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : true,
+          "schema" : {
+            "type" : "string"
+          }
+        } ],
+        "requestBody" : {
+          "content" : {
+            "application/json" : {
+              "schema" : {
+                "$ref" : "#/components/schemas/AppendConversationMessageRequest"
+              }
+            }
+          },
+          "required" : true
+        },
+        "responses" : {
+          "201" : {
+            "description" : "Created",
+            "content" : {
+              "*/*" : {
+                "schema" : {
+                  "$ref" : "#/components/schemas/ConversationMessageResponse"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
     "/api/v1/chat-sessions" : {
       "get" : {
         "tags" : [ "chat-session-controller" ],
-        "operationId" : "list_3",
+        "operationId" : "list_4",
         "parameters" : [ {
           "name" : "X-User-Id",
           "in" : "header",
@@ -715,11 +857,12 @@
               }
             }
           }
-        }
+        },
+        "deprecated" : true
       },
       "post" : {
         "tags" : [ "chat-session-controller" ],
-        "operationId" : "create_3",
+        "operationId" : "create_4",
         "parameters" : [ {
           "name" : "X-User-Id",
           "in" : "header",
@@ -749,13 +892,14 @@
               }
             }
           }
-        }
+        },
+        "deprecated" : true
       }
     },
     "/api/v1/chat-sessions/{id}/messages" : {
       "post" : {
         "tags" : [ "chat-session-controller" ],
-        "operationId" : "appendMessage",
+        "operationId" : "appendMessage_1",
         "parameters" : [ {
           "name" : "id",
           "in" : "path",
@@ -764,6 +908,13 @@
             "type" : "string",
             "format" : "uuid"
           }
+        }, {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : false,
+          "schema" : {
+            "type" : "string"
+          }
         } ],
         "requestBody" : {
           "content" : {
@@ -786,7 +937,8 @@
               }
             }
           }
-        }
+        },
+        "deprecated" : true
       }
     },
     "/api/v1/workspaces/{workspaceId}/setup" : {
@@ -1275,10 +1427,70 @@
         }
       }
     },
+    "/api/v1/conversations/{id}" : {
+      "get" : {
+        "tags" : [ "conversation-controller" ],
+        "operationId" : "get_3",
+        "parameters" : [ {
+          "name" : "id",
+          "in" : "path",
+          "required" : true,
+          "schema" : {
+            "type" : "string",
+            "format" : "uuid"
+          }
+        }, {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : true,
+          "schema" : {
+            "type" : "string"
+          }
+        } ],
+        "responses" : {
+          "200" : {
+            "description" : "OK",
+            "content" : {
+              "*/*" : {
+                "schema" : {
+                  "$ref" : "#/components/schemas/ConversationDetailResponse"
+                }
+              }
+            }
+          }
+        }
+      },
+      "delete" : {
+        "tags" : [ "conversation-controller" ],
+        "operationId" : "archive",
+        "parameters" : [ {
+          "name" : "id",
+          "in" : "path",
+          "required" : true,
+          "schema" : {
+            "type" : "string",
+            "format" : "uuid"
+          }
+        }, {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : true,
+          "schema" : {
+            "type" : "string"
+          }
+        } ],
+        "responses" : {
+          "204" : {
+            "description" : "No Content",
+            "content" : { }
+          }
+        }
+      }
+    },
     "/api/v1/chat-sessions/{id}" : {
       "get" : {
         "tags" : [ "chat-session-controller" ],
-        "operationId" : "get_3",
+        "operationId" : "get_4",
         "parameters" : [ {
           "name" : "id",
           "in" : "path",
@@ -1287,6 +1499,13 @@
             "type" : "string",
             "format" : "uuid"
           }
+        }, {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : false,
+          "schema" : {
+            "type" : "string"
+          }
         } ],
         "responses" : {
           "200" : {
@@ -1300,11 +1519,12 @@
               }
             }
           }
-        }
+        },
+        "deprecated" : true
       },
       "delete" : {
         "tags" : [ "chat-session-controller" ],
-        "operationId" : "archive",
+        "operationId" : "archive_1",
         "parameters" : [ {
           "name" : "id",
           "in" : "path",
@@ -1326,7 +1546,8 @@
             "description" : "OK",
             "content" : { }
           }
-        }
+        },
+        "deprecated" : true
       }
     },
     "/api/v1/agent-setups" : {
@@ -2093,6 +2314,93 @@
         },
         "required" : [ "url" ]
       },
+      "StartConversationRequest" : {
+        "type" : "object",
+        "properties" : {
+          "title" : {
+            "type" : [ "string", "null" ],
+            "maxLength" : 120,
+            "minLength" : 0
+          },
+          "kind" : {
+            "type" : [ "string", "null" ],
+            "enum" : [ "PLAIN", "KNOWLEDGE" ]
+          }
+        }
+      },
+      "ConversationResponse" : {
+        "type" : "object",
+        "properties" : {
+          "id" : {
+            "type" : "string",
+            "format" : "uuid"
+          },
+          "userId" : {
+            "type" : "string",
+            "format" : "uuid"
+          },
+          "title" : {
+            "type" : [ "string", "null" ]
+          },
+          "status" : {
+            "type" : "string"
+          },
+          "kind" : {
+            "type" : "string"
+          },
+          "createdAt" : {
+            "type" : "string",
+            "format" : "date-time"
+          },
+          "updatedAt" : {
+            "type" : "string",
+            "format" : "date-time"
+          }
+        },
+        "required" : [ "createdAt", "id", "kind", "status", "updatedAt", "userId" ]
+      },
+      "AppendConversationMessageRequest" : {
+        "type" : "object",
+        "properties" : {
+          "body" : {
+            "type" : [ "string", "null" ]
+          },
+          "content" : {
+            "type" : [ "string", "null" ]
+          },
+          "role" : {
+            "type" : [ "string", "null" ],
+            "enum" : [ "USER", "ASSISTANT", "SYSTEM" ]
+          }
+        }
+      },
+      "ConversationMessageResponse" : {
+        "type" : "object",
+        "properties" : {
+          "id" : {
+            "type" : "string",
+            "format" : "uuid"
+          },
+          "conversationId" : {
+            "type" : "string",
+            "format" : "uuid"
+          },
+          "role" : {
+            "type" : "string"
+          },
+          "body" : {
+            "type" : "string"
+          },
+          "content" : {
+            "type" : "string"
+          },
+          "createdAt" : {
+            "type" : "string",
+            "format" : "date-time"
+          }
+        },
+        "required" : [ "body", "content", "conversationId", "createdAt", "id", "role" ]
+      },
       "StartChatSessionRequest" : {
         "type" : "object",
         "properties" : {
@@ -2762,6 +3070,43 @@
         },
         "required" : [ "exists", "state" ]
       },
+      "ConversationDetailResponse" : {
+        "type" : "object",
+        "properties" : {
+          "id" : {
+            "type" : "string",
+            "format" : "uuid"
+          },
+          "userId" : {
+            "type" : "string",
+            "format" : "uuid"
+          },
+          "title" : {
+            "type" : [ "string", "null" ]
+          },
+          "status" : {
+            "type" : "string"
+          },
+          "kind" : {
+            "type" : "string"
+          },
+          "createdAt" : {
+            "type" : "string",
+            "format" : "date-time"
+          },
+          "updatedAt" : {
+            "type" : "string",
+            "format" : "date-time"
+          },
+          "messages" : {
+            "type" : "array",
+            "items" : {
+              "$ref" : "#/components/schemas/ConversationMessageResponse"
+            }
+          }
+        },
+        "required" : [ "createdAt", "id", "kind", "messages", "status", "updatedAt", "userId" ]
+      },
       "AgentSetupCatalogResponse" : {
         "type" : "object",
         "properties" : {
diff --git a/client-spec/openapi/agents-api.json b/client-spec/openapi/agents-api.json
index 830ed20..2102fd7 100644
--- a/client-spec/openapi/agents-api.json
+++ b/client-spec/openapi/agents-api.json
@@ -689,10 +689,152 @@
         }
       }
     },
+    "/api/v1/conversations" : {
+      "get" : {
+        "tags" : [ "conversation-controller" ],
+        "operationId" : "list_3",
+        "parameters" : [ {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : true,
+          "schema" : {
+            "type" : "string"
+          }
+        } ],
+        "responses" : {
+          "200" : {
+            "description" : "OK",
+            "content" : {
+              "*/*" : {
+                "schema" : {
+                  "type" : "array",
+                  "items" : {
+                    "$ref" : "#/components/schemas/ConversationResponse"
+                  }
+                }
+              }
+            }
+          }
+        }
+      },
+      "post" : {
+        "tags" : [ "conversation-controller" ],
+        "operationId" : "create_3",
+        "parameters" : [ {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : true,
+          "schema" : {
+            "type" : "string"
+          }
+        } ],
+        "requestBody" : {
+          "content" : {
+            "application/json" : {
+              "schema" : {
+                "$ref" : "#/components/schemas/StartConversationRequest"
+              }
+            }
+          },
+          "required" : true
+        },
+        "responses" : {
+          "201" : {
+            "description" : "Created",
+            "content" : {
+              "*/*" : {
+                "schema" : {
+                  "$ref" : "#/components/schemas/ConversationResponse"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
+    "/api/v1/conversations/{id}/messages" : {
+      "get" : {
+        "tags" : [ "conversation-controller" ],
+        "operationId" : "listMessages",
+        "parameters" : [ {
+          "name" : "id",
+          "in" : "path",
+          "required" : true,
+          "schema" : {
+            "type" : "string",
+            "format" : "uuid"
+          }
+        }, {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : true,
+          "schema" : {
+            "type" : "string"
+          }
+        } ],
+        "responses" : {
+          "200" : {
+            "description" : "OK",
+            "content" : {
+              "*/*" : {
+                "schema" : {
+                  "type" : "array",
+                  "items" : {
+                    "$ref" : "#/components/schemas/ConversationMessageResponse"
+                  }
+                }
+              }
+            }
+          }
+        }
+      },
+      "post" : {
+        "tags" : [ "conversation-controller" ],
+        "operationId" : "appendMessage",
+        "parameters" : [ {
+          "name" : "id",
+          "in" : "path",
+          "required" : true,
+          "schema" : {
+            "type" : "string",
+            "format" : "uuid"
+          }
+        }, {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : true,
+          "schema" : {
+            "type" : "string"
+          }
+        } ],
+        "requestBody" : {
+          "content" : {
+            "application/json" : {
+              "schema" : {
+                "$ref" : "#/components/schemas/AppendConversationMessageRequest"
+              }
+            }
+          },
+          "required" : true
+        },
+        "responses" : {
+          "201" : {
+            "description" : "Created",
+            "content" : {
+              "*/*" : {
+                "schema" : {
+                  "$ref" : "#/components/schemas/ConversationMessageResponse"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
     "/api/v1/chat-sessions" : {
       "get" : {
         "tags" : [ "chat-session-controller" ],
-        "operationId" : "list_3",
+        "operationId" : "list_4",
         "parameters" : [ {
           "name" : "X-User-Id",
           "in" : "header",
@@ -715,11 +857,12 @@
               }
             }
           }
-        }
+        },
+        "deprecated" : true
       },
       "post" : {
         "tags" : [ "chat-session-controller" ],
-        "operationId" : "create_3",
+        "operationId" : "create_4",
         "parameters" : [ {
           "name" : "X-User-Id",
           "in" : "header",
@@ -749,13 +892,14 @@
               }
             }
           }
-        }
+        },
+        "deprecated" : true
       }
     },
     "/api/v1/chat-sessions/{id}/messages" : {
       "post" : {
         "tags" : [ "chat-session-controller" ],
-        "operationId" : "appendMessage",
+        "operationId" : "appendMessage_1",
         "parameters" : [ {
           "name" : "id",
           "in" : "path",
@@ -764,6 +908,13 @@
             "type" : "string",
             "format" : "uuid"
           }
+        }, {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : false,
+          "schema" : {
+            "type" : "string"
+          }
         } ],
         "requestBody" : {
           "content" : {
@@ -786,7 +937,8 @@
               }
             }
           }
-        }
+        },
+        "deprecated" : true
       }
     },
     "/api/v1/workspaces/{workspaceId}/setup" : {
@@ -1275,10 +1427,70 @@
         }
       }
     },
+    "/api/v1/conversations/{id}" : {
+      "get" : {
+        "tags" : [ "conversation-controller" ],
+        "operationId" : "get_3",
+        "parameters" : [ {
+          "name" : "id",
+          "in" : "path",
+          "required" : true,
+          "schema" : {
+            "type" : "string",
+            "format" : "uuid"
+          }
+        }, {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : true,
+          "schema" : {
+            "type" : "string"
+          }
+        } ],
+        "responses" : {
+          "200" : {
+            "description" : "OK",
+            "content" : {
+              "*/*" : {
+                "schema" : {
+                  "$ref" : "#/components/schemas/ConversationDetailResponse"
+                }
+              }
+            }
+          }
+        }
+      },
+      "delete" : {
+        "tags" : [ "conversation-controller" ],
+        "operationId" : "archive",
+        "parameters" : [ {
+          "name" : "id",
+          "in" : "path",
+          "required" : true,
+          "schema" : {
+            "type" : "string",
+            "format" : "uuid"
+          }
+        }, {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : true,
+          "schema" : {
+            "type" : "string"
+          }
+        } ],
+        "responses" : {
+          "204" : {
+            "description" : "No Content",
+            "content" : { }
+          }
+        }
+      }
+    },
     "/api/v1/chat-sessions/{id}" : {
       "get" : {
         "tags" : [ "chat-session-controller" ],
-        "operationId" : "get_3",
+        "operationId" : "get_4",
         "parameters" : [ {
           "name" : "id",
           "in" : "path",
@@ -1287,6 +1499,13 @@
             "type" : "string",
             "format" : "uuid"
           }
+        }, {
+          "name" : "X-User-Id",
+          "in" : "header",
+          "required" : false,
+          "schema" : {
+            "type" : "string"
+          }
         } ],
         "responses" : {
           "200" : {
@@ -1300,11 +1519,12 @@
               }
             }
           }
-        }
+        },
+        "deprecated" : true
       },
       "delete" : {
         "tags" : [ "chat-session-controller" ],
-        "operationId" : "archive",
+        "operationId" : "archive_1",
         "parameters" : [ {
           "name" : "id",
           "in" : "path",
@@ -1326,7 +1546,8 @@
             "description" : "OK",
             "content" : { }
           }
-        }
+        },
+        "deprecated" : true
       }
     },
     "/api/v1/agent-setups" : {
@@ -2093,6 +2314,93 @@
         },
         "required" : [ "url" ]
       },
+      "StartConversationRequest" : {
+        "type" : "object",
+        "properties" : {
+          "title" : {
+            "type" : [ "string", "null" ],
+            "maxLength" : 120,
+            "minLength" : 0
+          },
+          "kind" : {
+            "type" : [ "string", "null" ],
+            "enum" : [ "PLAIN", "KNOWLEDGE" ]
+          }
+        }
+      },
+      "ConversationResponse" : {
+        "type" : "object",
+        "properties" : {
+          "id" : {
+            "type" : "string",
+            "format" : "uuid"
+          },
+          "userId" : {
+            "type" : "string",
+            "format" : "uuid"
+          },
+          "title" : {
+            "type" : [ "string", "null" ]
+          },
+          "status" : {
+            "type" : "string"
+          },
+          "kind" : {
+            "type" : "string"
+          },
+          "createdAt" : {
+            "type" : "string",
+            "format" : "date-time"
+          },
+          "updatedAt" : {
+            "type" : "string",
+            "format" : "date-time"
+          }
+        },
+        "required" : [ "createdAt", "id", "kind", "status", "updatedAt", "userId" ]
+      },
+      "AppendConversationMessageRequest" : {
+        "type" : "object",
+        "properties" : {
+          "body" : {
+            "type" : [ "string", "null" ]
+          },
+          "content" : {
+            "type" : [ "string", "null" ]
+          },
+          "role" : {
+            "type" : [ "string", "null" ],
+            "enum" : [ "USER", "ASSISTANT", "SYSTEM" ]
+          }
+        }
+      },
+      "ConversationMessageResponse" : {
+        "type" : "object",
+        "properties" : {
+          "id" : {
+            "type" : "string",
+            "format" : "uuid"
+          },
+          "conversationId" : {
+            "type" : "string",
+            "format" : "uuid"
+          },
+          "role" : {
+            "type" : "string"
+          },
+          "body" : {
+            "type" : "string"
+          },
+          "content" : {
+            "type" : "string"
+          },
+          "createdAt" : {
+            "type" : "string",
+            "format" : "date-time"
+          }
+        },
+        "required" : [ "body", "content", "conversationId", "createdAt", "id", "role" ]
+      },
       "StartChatSessionRequest" : {
         "type" : "object",
         "properties" : {
@@ -2762,6 +3070,43 @@
         },
         "required" : [ "exists", "state" ]
       },
+      "ConversationDetailResponse" : {
+        "type" : "object",
+        "properties" : {
+          "id" : {
+            "type" : "string",
+            "format" : "uuid"
+          },
+          "userId" : {
+            "type" : "string",
+            "format" : "uuid"
+          },
+          "title" : {
+            "type" : [ "string", "null" ]
+          },
+          "status" : {
+            "type" : "string"
+          },
+          "kind" : {
+            "type" : "string"
+          },
+          "createdAt" : {
+            "type" : "string",
+            "format" : "date-time"
+          },
+          "updatedAt" : {
+            "type" : "string",
+            "format" : "date-time"
+          },
+          "messages" : {
+            "type" : "array",
+            "items" : {
+              "$ref" : "#/components/schemas/ConversationMessageResponse"
+            }
+          }
+        },
+        "required" : [ "createdAt", "id", "kind", "messages", "status", "updatedAt", "userId" ]
+      },
       "AgentSetupCatalogResponse" : {
         "type" : "object",
         "properties" : {