diff --git a/shell/src/main/scala/orca/shell/actions/SessionAction.scala b/shell/src/main/scala/orca/shell/actions/SessionAction.scala
index fadf0d53..c9daaca7 100644
--- a/shell/src/main/scala/orca/shell/actions/SessionAction.scala
+++ b/shell/src/main/scala/orca/shell/actions/SessionAction.scala
@@ -43,8 +43,8 @@ private[shell] object SessionAction:
     val name = SessionNaming.displayName(session)
     val stage = session.stage.fold("")(s => s", stage '$s'")
     val branch = selection.manifest.branch.fold("")(b => s", on branch '$b'")
-    val crashedSuffix = if selection.crashed then " (crashed)" else ""
-    s"resuming session '$name' [$harnessName]$stage$branch, in ${selection.manifest.workDir}$crashedSuffix"
+    val crashed = SessionNaming.crashedSuffix(selection.observedStatus)
+    s"resuming session '$name' [$harnessName]$stage$branch, in ${selection.manifest.workDir}$crashed"
 
   /** Parses the manifest's stored `workDir` and confirms it's still a directory
     * — a checkout deleted after its run finished otherwise crashes resume:
diff --git a/shell/src/main/scala/orca/shell/cli/Cli.scala b/shell/src/main/scala/orca/shell/cli/Cli.scala
index 68944cd1..62955718 100644
--- a/shell/src/main/scala/orca/shell/cli/Cli.scala
+++ b/shell/src/main/scala/orca/shell/cli/Cli.scala
@@ -13,7 +13,7 @@ import org.jline.terminal.Terminal
 import orca.RawArgs
 import orca.shell.{ShellEnv, Tier, WorktreeScan}
 import orca.shell.run.LaunchResult
-import orca.shell.sessions.ManifestReader
+import orca.shell.sessions.ObservedStatus
 import orca.shell.ui.ShellUi
 import orca.subprocess.TtyProbe
 
@@ -309,7 +309,7 @@ private[cli] class CliCommands(using env: ShellEnv):
       list.value,
       json.value,
       isTty,
-      ManifestReader.pidAlive
+      ObservedStatus.processAlive
     )
 
   @main(doc =
diff --git a/shell/src/main/scala/orca/shell/cli/ContinueCli.scala b/shell/src/main/scala/orca/shell/cli/ContinueCli.scala
index 05c43f1f..627d9131 100644
--- a/shell/src/main/scala/orca/shell/cli/ContinueCli.scala
+++ b/shell/src/main/scala/orca/shell/cli/ContinueCli.scala
@@ -1,5 +1,6 @@
 package orca.shell.cli
 
+import orca.runner.manifest.AttemptManifest
 import orca.shell.ScanDirs
 import orca.shell.actions.SessionAction
 import orca.shell.sessions.{
@@ -17,10 +18,10 @@ import Cli.{actionFailure, complete, requireTty, usageFailure, withTerminal}
   */
 private[cli] object ContinueCli:
 
-  /** `continue`'s full behavior over explicit `dirs`/`tty`/`pidAlive` (test
+  /** `continue`'s full behavior over explicit `dirs`/`tty`/`processAlive` (test
     * seam) — tests seed each directory with `.orca/cache/attempts/` manifests,
-    * simulate a terminal or a pipe via `tty`, and fake pid liveness via
-    * `pidAlive`. The directories arrive resolved
+    * simulate a terminal or a pipe via `tty`, and fake process liveness via
+    * `processAlive`. The directories arrive resolved
     * ([[orca.shell.WorktreeScan.dirs]], at the real entry point), so nothing
     * here spawns git.
     */
@@ -30,10 +31,10 @@ private[cli] object ContinueCli:
       list: Boolean,
       json: Boolean,
       tty: Boolean,
-      pidAlive: Long => Boolean
+      processAlive: AttemptManifest => Boolean
   ): Int =
     val AttemptListing(attempts, warnings) =
-      ManifestReader.list(dirs.own, dirs.worktrees, pidAlive)
+      ManifestReader.list(dirs.own, dirs.worktrees, processAlive)
     warnings.foreach(Cli.diagnostic)
     val index = SessionIndex.of(attempts)
     if list then
diff --git a/shell/src/main/scala/orca/shell/cli/Tables.scala b/shell/src/main/scala/orca/shell/cli/Tables.scala
index 7143dbb7..02dd3f97 100644
--- a/shell/src/main/scala/orca/shell/cli/Tables.scala
+++ b/shell/src/main/scala/orca/shell/cli/Tables.scala
@@ -12,7 +12,12 @@ import orca.StagePath
 import orca.runner.manifest.SessionKind
 import orca.shell.flows.DiscoveredFlow
 import orca.settings.AgentSpec
-import orca.shell.sessions.{ResumeCommand, SessionIndex, SessionNaming}
+import orca.shell.sessions.{
+  ObservedStatus,
+  ResumeCommand,
+  SessionIndex,
+  SessionNaming
+}
 
 /** The CLI's table/JSON rendering (ADR 0021 §10) — the row shapes `list` and
   * `continue --list` emit, their jsoniter codecs, and the shared space-padded
@@ -50,8 +55,13 @@ private[cli] object Tables:
       lastActiveAt: String,
       resumable: Boolean,
       reason: Option[String],
-      crashed: Boolean
+      /** The attempt's status, `Crashed` included. */
+      attemptStatus: ObservedStatus
   )
+  private given ConfiguredJsonValueCodec[ObservedStatus] =
+    ConfiguredJsonValueCodec.derived[ObservedStatus](using
+      CodecMakerConfig.withDiscriminatorFieldName(None)
+    )
   // `withTransientEmpty`/`withTransientNone` false: `--json` output is for
   // scripts, which should see an always-present `reason` key (null when
   // unset) and `shadows`/similar fields rather than a silently vanishing one.
@@ -76,7 +86,7 @@ private[cli] object Tables:
         lastActiveAt = session.lastActiveAt.toString,
         resumable = gate.isRight,
         reason = gate.left.toOption,
-        crashed = selection.crashed
+        attemptStatus = selection.observedStatus
       )
 
   private[cli] def printSessionListing(
@@ -94,7 +104,7 @@ private[cli] object Tables:
           if r.resumable then ""
           else s"  not resumable: ${r.reason.getOrElse("")}"
         val sessionName =
-          r.sessionName + (if r.crashed then " (crashed)" else "") +
+          r.sessionName + SessionNaming.crashedSuffix(r.attemptStatus) +
             tag(r.workDir, r.branch)
         (
           r.id,
diff --git a/shell/src/main/scala/orca/shell/menu/ShellMenu.scala b/shell/src/main/scala/orca/shell/menu/ShellMenu.scala
index 400a16b3..37dfe6b4 100644
--- a/shell/src/main/scala/orca/shell/menu/ShellMenu.scala
+++ b/shell/src/main/scala/orca/shell/menu/ShellMenu.scala
@@ -8,6 +8,7 @@ import orca.shell.run.FlowLauncher
 import orca.shell.sessions.{
   AttemptListing,
   ManifestReader,
+  ObservedStatus,
   SessionIndex,
   SessionPicker
 }
@@ -49,7 +50,7 @@ private[shell] object ShellMenu:
       ManifestReader.list(
         scanDirs.own,
         scanDirs.worktrees,
-        ManifestReader.pidAlive
+        ObservedStatus.processAlive
       )
     warnings.foreach(ShellOutput.info)
     val continueSessionCount =
diff --git a/shell/src/main/scala/orca/shell/sessions/ManifestReader.scala b/shell/src/main/scala/orca/shell/sessions/ManifestReader.scala
index 9f181054..376e9121 100644
--- a/shell/src/main/scala/orca/shell/sessions/ManifestReader.scala
+++ b/shell/src/main/scala/orca/shell/sessions/ManifestReader.scala
@@ -1,20 +1,19 @@
 package orca.shell.sessions
 
 import orca.{AttemptId, OrcaDir}
-import orca.runner.manifest.{AttemptStatus, AttemptManifest}
+import orca.runner.manifest.AttemptManifest
 import orca.util.JsonFile
 
 import scala.util.control.NonFatal
 
-/** A manifest paired with its attempt's id (from the file name) and whether the
-  * attempt is now known to have crashed (status [[AttemptStatus.Running]] with
-  * a dead pid, ADR 0021 §8) — computed once here rather than re-derived by
-  * every caller.
+/** A manifest paired with its attempt's id (from the file name) and its
+  * [[ObservedStatus]] — read that rather than `manifest.status`, which cannot
+  * tell a crashed attempt from a running one.
   */
 private[shell] case class RecordedAttempt(
     id: AttemptId,
     manifest: AttemptManifest,
-    crashed: Boolean
+    observedStatus: ObservedStatus
 )
 
 /** What [[ManifestReader.list]] found: the continuable attempts, newest first,
@@ -46,23 +45,25 @@ private[shell] object ManifestReader:
     * parameters rather than one list, because that is the whole difference
     * between them.
     *
-    * A manifest with [[AttemptStatus.Running]] whose `pid` is no longer alive
-    * is a crashed attempt — its sessions are still offered, per ADR 0021 §8. An
-    * attempt that committed no session is left out: it has nothing to continue.
-    * Each directory's `.orca/cache/attempts/` is read passively
-    * ([[OrcaDir.attemptsPath]], not [[OrcaDir.ensureAttempts]]) — absent or
-    * empty contributes nothing and creates nothing on disk. A file that fails
-    * to parse as JSON, or doesn't match the `AttemptManifest` schema — which
-    * includes a timestamp that isn't an `Instant` — is skipped with a warning
-    * naming the file rather than aborting the whole listing.
+    * A crashed attempt ([[ObservedStatus.Crashed]], decided by `processAlive`;
+    * [[ObservedStatus.processAlive]] in production) still has its sessions
+    * offered, per ADR 0021 §8. An attempt that committed no session is left
+    * out: it has nothing to continue. Each directory's `.orca/cache/attempts/`
+    * is read passively ([[OrcaDir.attemptsPath]], not
+    * [[OrcaDir.ensureAttempts]]) — absent or empty contributes nothing and
+    * creates nothing on disk. A file that fails to parse as JSON, or doesn't
+    * match the `AttemptManifest` schema — which includes a timestamp that isn't
+    * an `Instant` — is skipped with a warning naming the file rather than
+    * aborting the whole listing.
     */
   def list(
       own: os.Path,
       otherWorktrees: List[os.Path],
-      pidAlive: Long => Boolean
+      processAlive: AttemptManifest => Boolean
   ): AttemptListing =
     val perDir =
-      readAttemptsDir(own, pidAlive) :: otherWorktrees.map(guarded(_, pidAlive))
+      readAttemptsDir(own, processAlive) ::
+        otherWorktrees.map(guarded(_, processAlive))
     AttemptListing(
       perDir.flatMap(_.attempts).sortBy(_.manifest.startedAt).reverse,
       perDir.flatMap(_.warnings)
@@ -70,9 +71,9 @@ private[shell] object ManifestReader:
 
   private def guarded(
       workDir: os.Path,
-      pidAlive: Long => Boolean
+      processAlive: AttemptManifest => Boolean
   ): AttemptListing =
-    try readAttemptsDir(workDir, pidAlive)
+    try readAttemptsDir(workDir, processAlive)
     catch
       case NonFatal(e) =>
         AttemptListing(Nil, List(s"skipping $workDir: ${firstLine(e)}"))
@@ -88,7 +89,7 @@ private[shell] object ManifestReader:
     */
   private def readAttemptsDir(
       workDir: os.Path,
-      pidAlive: Long => Boolean
+      processAlive: AttemptManifest => Boolean
   ): AttemptListing =
     val dir = OrcaDir.attemptsPath(workDir)
     OrcaDir.assertNoOrcaSymlinks(workDir, dir)
@@ -98,20 +99,12 @@ private[shell] object ManifestReader:
         os.list(dir).filter(OrcaDir.isManifest).toList.map(readManifest)
       val attempts = results.collect:
         case Right((id, m)) if m.continuable =>
-          RecordedAttempt(id, m, crashed(m, pidAlive))
+          RecordedAttempt(id, m, ObservedStatus.of(m, processAlive))
       AttemptListing(
         attempts,
         results.collect { case Left(warning) => warning }
       )
 
-  private def crashed(
-      manifest: AttemptManifest,
-      pidAlive: Long => Boolean
-  ): Boolean =
-    manifest.status match
-      case AttemptStatus.Running => !pidAlive(manifest.pid)
-      case AttemptStatus.Succeeded | AttemptStatus.Failed => false
-
   /** A missing file is a warning too: the listing saw it and the read found
     * nothing, which for a directory the shell does not control is a race with
     * pruning or removal worth a line.
@@ -132,12 +125,3 @@ private[shell] object ManifestReader:
       case JsonFile.Read.Unreadable(reason) =>
         Left(s"skipping $file: $reason")
       case JsonFile.Read.Corrupt(reason) => Left(s"skipping $file: $reason")
-
-  /** The production value of [[list]]'s `pidAlive` parameter (ADR 0021 §8):
-    * `ProcessHandle.of` finds nothing for a pid that's been reaped — treated as
-    * not alive, same as a live handle reporting `isAlive == false`. Shared by
-    * the interactive menu and the CLI's `continue`, so both derive an attempt's
-    * crashed status the same way.
-    */
-  private[shell] def pidAlive(pid: Long): Boolean =
-    ProcessHandle.of(pid).map[Boolean](_.isAlive).orElse(false)
diff --git a/shell/src/main/scala/orca/shell/sessions/ObservedStatus.scala b/shell/src/main/scala/orca/shell/sessions/ObservedStatus.scala
new file mode 100644
index 00000000..5c985c02
--- /dev/null
+++ b/shell/src/main/scala/orca/shell/sessions/ObservedStatus.scala
@@ -0,0 +1,47 @@
+package orca.shell.sessions
+
+import orca.runner.manifest.{AttemptManifest, AttemptStatus}
+
+import java.time.Duration
+import scala.jdk.OptionConverters.*
+
+/** An attempt's [[AttemptStatus]] as the shell sees it now: a manifest still
+  * [[AttemptStatus.Running]] whose process is gone is `Crashed` (ADR 0021 §8).
+  */
+private[shell] enum ObservedStatus:
+  case Running, Succeeded, Failed, Crashed
+
+private[shell] object ObservedStatus:
+
+  /** `processAlive` answers whether the process that wrote `manifest` still
+    * runs — [[processAlive]] in production.
+    */
+  def of(
+      manifest: AttemptManifest,
+      processAlive: AttemptManifest => Boolean
+  ): ObservedStatus =
+    manifest.status match
+      case AttemptStatus.Running =>
+        if processAlive(manifest) then Running else Crashed
+      case AttemptStatus.Succeeded => Succeeded
+      case AttemptStatus.Failed    => Failed
+
+  /** Whether `manifest.pid` names a live process that started no later than
+    * `startedAt` (which the attempt takes inside that process) — a later start
+    * means the pid was reused. The slack absorbs wall-clock steps, which shift
+    * the start instants the OS reports; a crashed attempt's pid being reused
+    * within it is negligible. An unknown start instant counts as alive.
+    */
+  def processAlive(manifest: AttemptManifest): Boolean =
+    ProcessHandle
+      .of(manifest.pid)
+      .toScala
+      .filter(_.isAlive)
+      .exists: handle =>
+        handle
+          .info()
+          .startInstant()
+          .toScala
+          .forall(!_.isAfter(manifest.startedAt.plus(ProcessStartSlack)))
+
+  private val ProcessStartSlack = Duration.ofMinutes(1)
diff --git a/shell/src/main/scala/orca/shell/sessions/SessionIndex.scala b/shell/src/main/scala/orca/shell/sessions/SessionIndex.scala
index 56cfaa44..121f4213 100644
--- a/shell/src/main/scala/orca/shell/sessions/SessionIndex.scala
+++ b/shell/src/main/scala/orca/shell/sessions/SessionIndex.scala
@@ -166,7 +166,7 @@ private[shell] object SessionIndex:
         SessionRef(attempt.id, i + 1),
         attempt.manifest,
         session,
-        attempt.crashed
+        attempt.observedStatus
       )
     val byLineage = all.groupBy(LineageKey.of)
     val lineages = byLineage.collect:
diff --git a/shell/src/main/scala/orca/shell/sessions/SessionNaming.scala b/shell/src/main/scala/orca/shell/sessions/SessionNaming.scala
index 6fb61b5d..a9fa0eeb 100644
--- a/shell/src/main/scala/orca/shell/sessions/SessionNaming.scala
+++ b/shell/src/main/scala/orca/shell/sessions/SessionNaming.scala
@@ -38,3 +38,10 @@ private[shell] object SessionNaming:
     */
   def displayName(session: ManifestSession): String =
     session.minted.fold(session.agent)(_.name)
+
+  /** ` (crashed)` for a crashed attempt's session; nothing otherwise. */
+  def crashedSuffix(status: ObservedStatus): String = status match
+    case ObservedStatus.Crashed => " (crashed)"
+    case ObservedStatus.Running | ObservedStatus.Succeeded |
+        ObservedStatus.Failed =>
+      ""
diff --git a/shell/src/main/scala/orca/shell/sessions/SessionPicker.scala b/shell/src/main/scala/orca/shell/sessions/SessionPicker.scala
index bf578236..7ca26019 100644
--- a/shell/src/main/scala/orca/shell/sessions/SessionPicker.scala
+++ b/shell/src/main/scala/orca/shell/sessions/SessionPicker.scala
@@ -151,5 +151,5 @@ private[shell] object SessionPicker:
   private def rowTail(selection: SessionSelection, marker: String): String =
     val harness = AgentSpec.harnessNameFor(selection.session.backend)
     val branch = selection.manifest.branch.fold("")(b => s" on $b")
-    val crashed = if selection.crashed then " (crashed)" else ""
+    val crashed = SessionNaming.crashedSuffix(selection.observedStatus)
     s"[$harness]$marker$branch$crashed"
diff --git a/shell/src/main/scala/orca/shell/sessions/SessionSelection.scala b/shell/src/main/scala/orca/shell/sessions/SessionSelection.scala
index a78f6577..af24e73b 100644
--- a/shell/src/main/scala/orca/shell/sessions/SessionSelection.scala
+++ b/shell/src/main/scala/orca/shell/sessions/SessionSelection.scala
@@ -5,10 +5,9 @@ import orca.runner.manifest.{ManifestSession, AttemptManifest}
 /** One recorded session with the attempt manifest it came from — everything
   * [[orca.shell.actions.SessionAction.resume]] needs (the harness command comes
   * from the session; the working directory comes from the manifest, which may
-  * differ from the shell's own cwd). `crashed` carries the attempt's crashed
-  * status (status `"Running"` with a dead pid) through to display — resuming
-  * still offers a crashed attempt's sessions (ADR 0021 §8), but the notice
-  * should say so.
+  * differ from the shell's own cwd). `observedStatus` is the attempt's, carried
+  * through to display — resuming still offers a crashed attempt's sessions (ADR
+  * 0021 §8), but the notice should say so.
   *
   * Lives in `sessions` so [[SessionIndex]] can construct it without `sessions`
   * depending back on `actions`, which — with `actions/SessionAction` already
@@ -18,5 +17,5 @@ private[shell] case class SessionSelection(
     ref: SessionRef,
     manifest: AttemptManifest,
     session: ManifestSession,
-    crashed: Boolean
+    observedStatus: ObservedStatus
 )
diff --git a/shell/src/test/scala/orca/shell/cli/CliTest.scala b/shell/src/test/scala/orca/shell/cli/CliTest.scala
index b1ba04ca..3adef4bf 100644
--- a/shell/src/test/scala/orca/shell/cli/CliTest.scala
+++ b/shell/src/test/scala/orca/shell/cli/CliTest.scala
@@ -3,7 +3,7 @@ package orca.shell.cli
 import mainargs.{ParserForMethods, TokensReader}
 import orca.StagePath
 import orca.agents.{BackendTag, SessionKey}
-import orca.runner.manifest.{AttemptStatus, ManifestSession}
+import orca.runner.manifest.{AttemptManifest, AttemptStatus, ManifestSession}
 import orca.settings.{AgentSettings, AgentSpec, SettingsFile, SettingsScope}
 import orca.shell.{ScanDirs, ShellEnv, TestShellEnv, Tier}
 import orca.shell.actions.SessionAction
@@ -13,6 +13,7 @@ import orca.shell.flows.DiscoveredFlow
 import orca.shell.run.LaunchResult
 import orca.shell.sessions.{
   ManifestFixtures,
+  ObservedStatus,
   RecordedAttempt,
   SessionIndex,
   SessionPicker,
@@ -42,7 +43,7 @@ class CliTest extends munit.FunSuite:
   /** `runContinue`'s liveness check: every recorded `Running` attempt reads as
     * crashed.
     */
-  private val everyPidDead: Long => Boolean = _ => false
+  private val everyProcessDead: AttemptManifest => Boolean = _ => false
 
   private def invoke(args: String*): Either[String, Any] =
     import Cli.given
@@ -757,8 +758,7 @@ class CliTest extends munit.FunSuite:
               lastActiveAt = "2026-07-18T09:45:00Z"
             )
           )
-        ),
-        crashed = false
+        )
       ),
       ManifestFixtures.recorded(
         manifest(
@@ -775,8 +775,7 @@ class CliTest extends munit.FunSuite:
               wireId = None
             )
           )
-        ),
-        crashed = false
+        )
       )
     )
 
@@ -804,8 +803,7 @@ class CliTest extends munit.FunSuite:
             durable(sessionName = "plan", lastActiveAt = "2026-07-18T09:45:00Z")
               .copy(minted = None)
           )
-        ),
-        crashed = false
+        )
       )
     )
     assertEquals(
@@ -935,8 +933,7 @@ class CliTest extends munit.FunSuite:
           sessions = List(
             durable(sessionName = sessionName, lastActiveAt = lastActiveAt)
           )
-        ),
-        crashed = false
+        )
       )
     // The older attempt holds the more recently active session.
     val attempts = List(
@@ -966,8 +963,7 @@ class CliTest extends munit.FunSuite:
               wireId = None
             )
           )
-        ),
-        crashed = false
+        )
       )
     )
     assertEquals(
@@ -986,8 +982,7 @@ class CliTest extends munit.FunSuite:
         sessions = List(
           durable(sessionName = "other", lastActiveAt = "2026-07-16T09:30:00Z")
         )
-      ),
-      crashed = false
+      )
     )
     assertEquals(
       SessionIndex.of(attempts).resolve(Some("older")),
@@ -1007,8 +1002,7 @@ class CliTest extends munit.FunSuite:
           startedAt = "2026-07-18T08:00:00Z",
           branch = Some("feature/x"),
           sessions = List(durable(lastActiveAt = lastActiveAt))
-        ),
-        crashed = false
+        )
       )
     val attempts = List(
       onBranch("/repo/a", "2026-07-18T09:30:00Z"),
@@ -1056,8 +1050,7 @@ class CliTest extends munit.FunSuite:
                 StagePath.FlowBody.child("Task: wire the parser", 0)
             )
           )
-        ),
-        crashed = false
+        )
       )
     )
     assertEquals(
@@ -1086,8 +1079,7 @@ class CliTest extends munit.FunSuite:
             durableAgent("agentA", "shared", "2026-07-18T09:30:00Z"),
             durableAgent("agentB", "shared", "2026-07-18T09:20:00Z")
           )
-        ),
-        crashed = false
+        )
       )
     )
     assertEquals(
@@ -1116,8 +1108,7 @@ class CliTest extends munit.FunSuite:
               lastActiveAt = "2026-07-18T09:30:00Z"
             )
           )
-        ),
-        crashed = false
+        )
       ),
       ManifestFixtures.recorded(
         manifest(
@@ -1129,8 +1120,7 @@ class CliTest extends munit.FunSuite:
               lastActiveAt = "2026-07-18T08:30:00Z"
             )
           )
-        ),
-        crashed = false
+        )
       )
     )
     assertEquals(
@@ -1160,8 +1150,7 @@ class CliTest extends munit.FunSuite:
                 branch = Some(branch),
                 sessions =
                   List(durable(lastActiveAt = s"2026-07-18T1${i}:00:00Z"))
-              ),
-              crashed = false
+              )
             )
     assertEquals(
       SessionPicker
@@ -1193,8 +1182,7 @@ class CliTest extends munit.FunSuite:
               sessionStage = StagePath.FlowBody.child("Task: wire", 0)
             )
           )
-        ),
-        crashed = false
+        )
       )
     )
     val labels = SessionPicker
@@ -1222,8 +1210,7 @@ class CliTest extends munit.FunSuite:
               sessionStage = StagePath.FlowBody.child("Task: parse", 0)
             )
           )
-        ),
-        crashed = false
+        )
       )
     )
     val labels = SessionPicker
@@ -1244,8 +1231,7 @@ class CliTest extends munit.FunSuite:
                 StagePath.FlowBody.child("Task: wire the parser", 0)
             )
           )
-        ),
-        crashed = false
+        )
       )
     )
     assertEquals(
@@ -1266,8 +1252,7 @@ class CliTest extends munit.FunSuite:
               lastActiveAt = "2026-07-18T09:30:00Z"
             )
           )
-        ),
-        crashed = false
+        )
       ),
       ManifestFixtures.recorded(
         manifest(
@@ -1278,8 +1263,7 @@ class CliTest extends munit.FunSuite:
               lastActiveAt = "2026-07-18T08:30:00Z"
             )
           )
-        ),
-        crashed = false
+        )
       )
     )
     val labels = SessionPicker
@@ -1308,8 +1292,7 @@ class CliTest extends munit.FunSuite:
     val selection =
       ManifestFixtures.selection(
         attempt.manifest,
-        attempt.manifest.sessions.head,
-        crashed = false
+        attempt.manifest.sessions.head
       )
     assertEquals(
       SessionAction.resumeNotice(selection),
@@ -1323,8 +1306,7 @@ class CliTest extends munit.FunSuite:
     val selection =
       ManifestFixtures.selection(
         attempt.manifest,
-        withStage,
-        crashed = false
+        withStage
       )
     assertEquals(
       SessionAction.resumeNotice(selection),
@@ -1337,7 +1319,7 @@ class CliTest extends munit.FunSuite:
       ManifestFixtures.selection(
         attempt.manifest,
         attempt.manifest.sessions.head,
-        crashed = true
+        observedStatus = ObservedStatus.Crashed
       )
     assertEquals(
       SessionAction.resumeNotice(selection),
@@ -1381,7 +1363,7 @@ class CliTest extends munit.FunSuite:
             list = true,
             json = true,
             tty = false,
-            pidAlive = everyPidDead
+            processAlive = everyProcessDead
           ),
         ExitCodes.Ok
       )
@@ -1430,7 +1412,7 @@ class CliTest extends munit.FunSuite:
           list = true,
           json = false,
           tty = false,
-          pidAlive = everyPidDead
+          processAlive = everyProcessDead
         ),
         ExitCodes.Ok
       )
@@ -1449,7 +1431,7 @@ class CliTest extends munit.FunSuite:
           list = true,
           json = false,
           tty = false,
-          pidAlive = everyPidDead
+          processAlive = everyProcessDead
         ),
         ExitCodes.Ok
       )
@@ -1468,7 +1450,7 @@ class CliTest extends munit.FunSuite:
           list = true,
           json = true,
           tty = false,
-          pidAlive = everyPidDead
+          processAlive = everyProcessDead
         ),
         ExitCodes.Ok
       )
@@ -1492,7 +1474,7 @@ class CliTest extends munit.FunSuite:
           list = true,
           json = json,
           tty = false,
-          pidAlive = everyPidDead
+          processAlive = everyProcessDead
         ),
         ExitCodes.Ok
       )
@@ -1529,7 +1511,7 @@ class CliTest extends munit.FunSuite:
           list = true,
           json = true,
           tty = false,
-          pidAlive = everyPidDead
+          processAlive = everyProcessDead
         ),
         ExitCodes.Ok
       )
@@ -1537,7 +1519,9 @@ class CliTest extends munit.FunSuite:
     assert(out.contains("\"kind\":\"Durable\""), out)
     assert(out.contains("\"kind\":\"Ephemeral\""), out)
 
-  test("runContinue --list --json: a crashed attempt reports crashed=true"):
+  test(
+    "runContinue --list --json: a crashed attempt reports attemptStatus Crashed"
+  ):
     val dir = TempDirs.dir()
     writeCrashedManifest(dir)
     val out = captured(
@@ -1549,12 +1533,12 @@ class CliTest extends munit.FunSuite:
             list = true,
             json = true,
             tty = false,
-            pidAlive = everyPidDead
+            processAlive = everyProcessDead
           ),
         ExitCodes.Ok
       )
     )
-    assert(out.contains("\"crashed\":true"), out)
+    assert(out.contains("\"attemptStatus\":\"Crashed\""), out)
 
   test(
     "runContinue --list: a crashed attempt's table row is suffixed (crashed)"
@@ -1570,7 +1554,7 @@ class CliTest extends munit.FunSuite:
             list = true,
             json = false,
             tty = false,
-            pidAlive = everyPidDead
+            processAlive = everyProcessDead
           ),
         ExitCodes.Ok
       )
@@ -1604,7 +1588,7 @@ class CliTest extends munit.FunSuite:
             list = false,
             json = false,
             tty = true,
-            pidAlive = everyPidDead
+            processAlive = everyProcessDead
           ),
         ExitCodes.ActionFailed
       )
diff --git a/shell/src/test/scala/orca/shell/sessions/ManifestFixtures.scala b/shell/src/test/scala/orca/shell/sessions/ManifestFixtures.scala
index 0cab8648..d44d1b1a 100644
--- a/shell/src/test/scala/orca/shell/sessions/ManifestFixtures.scala
+++ b/shell/src/test/scala/orca/shell/sessions/ManifestFixtures.scala
@@ -81,19 +81,32 @@ private[shell] object ManifestFixtures:
     */
   def recorded(
       manifest: AttemptManifest,
-      crashed: Boolean = false
+      observedStatus: ObservedStatus
   ): RecordedAttempt =
     RecordedAttempt(
       AttemptId(manifest.startedAt, manifest.pid),
       manifest,
-      crashed
+      observedStatus
     )
 
+  /** [[recorded]] with the writing process still alive. */
+  def recorded(manifest: AttemptManifest): RecordedAttempt =
+    recorded(manifest, ObservedStatus.of(manifest, _ => true))
+
+  /** `session`, recorded in `manifest`, as a [[SessionIndex]] holds it, with
+    * the writing process still alive.
+    */
+  def selection(
+      manifest: AttemptManifest,
+      session: ManifestSession
+  ): SessionSelection =
+    selection(manifest, session, ObservedStatus.of(manifest, _ => true))
+
   /** `session`, recorded in `manifest`, as a [[SessionIndex]] holds it. */
   def selection(
       manifest: AttemptManifest,
       session: ManifestSession,
-      crashed: Boolean = false
+      observedStatus: ObservedStatus
   ): SessionSelection =
     SessionSelection(
       SessionRef(
@@ -102,7 +115,7 @@ private[shell] object ManifestFixtures:
       ),
       manifest,
       session,
-      crashed
+      observedStatus
     )
 
   /** Writes `manifest` where `ManifestReader` lists `dir`'s attempts, under the
diff --git a/shell/src/test/scala/orca/shell/sessions/ManifestReaderTest.scala b/shell/src/test/scala/orca/shell/sessions/ManifestReaderTest.scala
index aa8cf7a4..ba18e485 100644
--- a/shell/src/test/scala/orca/shell/sessions/ManifestReaderTest.scala
+++ b/shell/src/test/scala/orca/shell/sessions/ManifestReaderTest.scala
@@ -1,14 +1,15 @@
 package orca.shell.sessions
 
 import orca.{AttemptId, OrcaDir, OrcaFlowException}
+import orca.runner.manifest.AttemptManifest
 import orca.testkit.TempDirs
 
 import java.time.Instant
 
 class ManifestReaderTest extends munit.FunSuite:
 
-  private val alwaysDead: Long => Boolean = _ => false
-  private val alwaysAlive: Long => Boolean = _ => true
+  private val alwaysDead: AttemptManifest => Boolean = _ => false
+  private val alwaysAlive: AttemptManifest => Boolean = _ => true
 
   private def attemptsDir(workDir: os.Path): os.Path =
     workDir / ".orca" / "cache" / "attempts"
@@ -190,9 +191,9 @@ class ManifestReaderTest extends munit.FunSuite:
     val AttemptListing(attempts, warnings) =
       ManifestReader.list(workDir, Nil, alwaysDead)
     assertEquals(warnings, Nil)
-    assertEquals(attempts.map(_.crashed), List(true))
+    assertEquals(attempts.map(_.observedStatus), List(ObservedStatus.Crashed))
 
-  test("a running manifest with a live pid is included and not marked crashed"):
+  test("a running manifest with a live pid is included and running"):
     val workDir = TempDirs.dir()
     writeManifest(
       workDir,
@@ -203,7 +204,7 @@ class ManifestReaderTest extends munit.FunSuite:
     val AttemptListing(attempts, warnings) =
       ManifestReader.list(workDir, Nil, alwaysAlive)
     assertEquals(warnings, Nil)
-    assertEquals(attempts.map(_.crashed), List(false))
+    assertEquals(attempts.map(_.observedStatus), List(ObservedStatus.Running))
 
   test(
     "list skips a manifest with an unrecognised outcome, warning by filename"
@@ -241,17 +242,17 @@ class ManifestReaderTest extends munit.FunSuite:
       warnings.head
     )
 
-  test("a finished manifest is never marked crashed, even with a dead pid"):
+  test("a failed manifest with a dead pid is not crashed"):
     val workDir = TempDirs.dir()
     writeManifest(
       workDir,
       startedAt = "2026-07-18T10:00:00Z",
       pid = 999999,
-      status = "Succeeded"
+      status = "Failed"
     )
     val AttemptListing(attempts, _) =
       ManifestReader.list(workDir, Nil, alwaysDead)
-    assertEquals(attempts.map(_.crashed), List(false))
+    assertEquals(attempts.map(_.observedStatus), List(ObservedStatus.Failed))
 
   test(
     "list skips a manifest whose minted key has no stage, warning by filename"
diff --git a/shell/src/test/scala/orca/shell/sessions/ManifestRoundTripTest.scala b/shell/src/test/scala/orca/shell/sessions/ManifestRoundTripTest.scala
index 25ae9784..799c78ac 100644
--- a/shell/src/test/scala/orca/shell/sessions/ManifestRoundTripTest.scala
+++ b/shell/src/test/scala/orca/shell/sessions/ManifestRoundTripTest.scala
@@ -48,10 +48,10 @@ class ManifestRoundTripTest extends munit.FunSuite:
       writer.finish(AttemptOutcome.Succeeded)
 
     val AttemptListing(attempts, warnings) =
-      ManifestReader.list(workDir, Nil, pidAlive = _ => true)
+      ManifestReader.list(workDir, Nil, processAlive = _ => true)
     assertEquals(warnings, Nil)
     assertEquals(attempts.size, 1)
-    assertEquals(attempts.head.crashed, false)
+    assertEquals(attempts.head.observedStatus, ObservedStatus.Succeeded)
     val session = attempts.head.manifest.sessions.head
     assertEquals(session.backend, BackendTag.ClaudeCode)
     assertEquals(session.wireId, Some("wire-1"))
diff --git a/shell/src/test/scala/orca/shell/sessions/ObservedStatusTest.scala b/shell/src/test/scala/orca/shell/sessions/ObservedStatusTest.scala
new file mode 100644
index 00000000..d2bfd24b
--- /dev/null
+++ b/shell/src/test/scala/orca/shell/sessions/ObservedStatusTest.scala
@@ -0,0 +1,30 @@
+package orca.shell.sessions
+
+import java.time.Instant
+
+class ObservedStatusTest extends munit.FunSuite:
+
+  private def attempt(pid: Long, startedAt: Instant) =
+    ManifestFixtures.manifest(
+      pid = pid,
+      startedAt = startedAt.toString,
+      sessions = Nil
+    )
+
+  test(
+    "processAlive: a process started within the slack after the attempt is alive"
+  ):
+    val self = ProcessHandle.current()
+    val startedAt = self.info().startInstant().get().minusSeconds(30)
+    assert(ObservedStatus.processAlive(attempt(self.pid(), startedAt)))
+
+  test("processAlive: a live process started after the attempt reused its pid"):
+    val self = ProcessHandle.current()
+    assert(!ObservedStatus.processAlive(attempt(self.pid(), Instant.EPOCH)))
+
+  test("processAlive: an exited process is not alive"):
+    val exited = os.proc("true").spawn()
+    assertEquals(exited.wrapped.waitFor(), 0)
+    assert(
+      !ObservedStatus.processAlive(attempt(exited.wrapped.pid(), Instant.now()))
+    )
diff --git a/shell/src/test/scala/orca/shell/sessions/SessionPickerTest.scala b/shell/src/test/scala/orca/shell/sessions/SessionPickerTest.scala
index 6d3e61ad..3abdb68f 100644
--- a/shell/src/test/scala/orca/shell/sessions/SessionPickerTest.scala
+++ b/shell/src/test/scala/orca/shell/sessions/SessionPickerTest.scala
@@ -30,8 +30,7 @@ class SessionPickerTest extends munit.FunSuite:
             lastActiveAt = "2026-07-16T09:01:00Z"
           )
         )
-      ),
-      crashed = false
+      )
     )
     val attempt2 = ManifestFixtures.recorded(
       manifest(
@@ -54,8 +53,7 @@ class SessionPickerTest extends munit.FunSuite:
             lastActiveAt = "2026-07-17T09:21:00Z"
           )
         )
-      ),
-      crashed = false
+      )
     )
     val attempt3 = ManifestFixtures.recorded(
       manifest(
@@ -72,8 +70,7 @@ class SessionPickerTest extends munit.FunSuite:
             lastActiveAt = "2026-07-18T09:40:00Z"
           )
         )
-      ),
-      crashed = false
+      )
     )
     List(
       attempt3,
@@ -163,8 +160,7 @@ class SessionPickerTest extends munit.FunSuite:
         sessions = List(
           durable(stage = Some("Plan"), lastActiveAt = "2026-07-17T09:05:00Z")
         )
-      ),
-      crashed = false
+      )
     )
     val attempt2 = ManifestFixtures.recorded(
       manifest(
@@ -172,8 +168,7 @@ class SessionPickerTest extends munit.FunSuite:
         sessions = List(
           durable(stage = Some("Task"), lastActiveAt = "2026-07-18T09:05:00Z")
         )
-      ),
-      crashed = false
+      )
     )
     val rows =
       SessionPicker.sessionRows(
@@ -200,8 +195,7 @@ class SessionPickerTest extends munit.FunSuite:
             stage = Some("Task: add auth")
           )
         )
-      ),
-      crashed = false
+      )
     )
     assertEquals(
       SessionPicker
@@ -216,8 +210,7 @@ class SessionPickerTest extends munit.FunSuite:
     "sessionRows omits the earlier-occurrences expander when there's only one occurrence"
   ):
     val run = ManifestFixtures.recorded(
-      manifest(sessions = List(durable())),
-      crashed = false
+      manifest(sessions = List(durable()))
     )
     assertEquals(
       SessionPicker
@@ -228,8 +221,7 @@ class SessionPickerTest extends munit.FunSuite:
 
   test("sessionRows singularises a count of 1 in the expander label"):
     val run = ManifestFixtures.recorded(
-      manifest(sessions = List(durable(), ephemeral())),
-      crashed = false
+      manifest(sessions = List(durable(), ephemeral()))
     )
     assertEquals(
       SessionPicker
@@ -262,8 +254,7 @@ class SessionPickerTest extends munit.FunSuite:
             lastActiveAt = "2026-07-18T09:05:00Z"
           )
         )
-      ),
-      crashed = false
+      )
     )
     assertEquals(
       SessionPicker
@@ -292,8 +283,7 @@ class SessionPickerTest extends munit.FunSuite:
             lastActiveAt = "2026-07-18T09:05:00Z"
           )
         )
-      ),
-      crashed = false
+      )
     )
     val rows =
       SessionPicker.sessionRows(SessionIndex.of(List(run)), expanded = false)
@@ -311,8 +301,7 @@ class SessionPickerTest extends munit.FunSuite:
       "feat-b" -> "2026-07-18T09:00:00Z"
     ).map: (b, at) =>
       ManifestFixtures.recorded(
-        manifest(branch = Some(b), sessions = List(durable(lastActiveAt = at))),
-        crashed = false
+        manifest(branch = Some(b), sessions = List(durable(lastActiveAt = at)))
       )
     assertEquals(
       SessionPicker
@@ -331,8 +320,7 @@ class SessionPickerTest extends munit.FunSuite:
           manifest(
             branch = Some("feat-a"),
             sessions = List(durable(lastActiveAt = at))
-          ),
-          crashed = false
+          )
         )
     assertEquals(
       SessionPicker
@@ -361,8 +349,7 @@ class SessionPickerTest extends munit.FunSuite:
           startedAt = startedAt,
           branch = Some("feat-a"),
           sessions = sessions
-        ),
-        crashed = false
+        )
       )
     assertEquals(
       SessionPicker
@@ -379,7 +366,7 @@ class SessionPickerTest extends munit.FunSuite:
     val run =
       ManifestFixtures.recorded(
         manifest(sessions = List(durable()), branch = Some("feat-a")),
-        crashed = true
+        observedStatus = ObservedStatus.Crashed
       )
     assertEquals(
       SessionPicker
@@ -390,10 +377,7 @@ class SessionPickerTest extends munit.FunSuite:
 
   test("sessionRows disables a wireId-less session, naming its harness"):
     val run = ManifestFixtures.recorded(
-      manifest(sessions =
-        List(durable(backend = BackendTag.Pi, wireId = None))
-      ),
-      crashed = false
+      manifest(sessions = List(durable(backend = BackendTag.Pi, wireId = None)))
     )
     assertEquals(
       SessionPicker
@@ -405,8 +389,7 @@ class SessionPickerTest extends munit.FunSuite:
   test("sessionRows enables a claude session with a wireId"):
     val run =
       ManifestFixtures.recorded(
-        manifest(sessions = List(durable())),
-        crashed = false
+        manifest(sessions = List(durable()))
       )
     assertEquals(
       SessionPicker