diff --git a/apps/desktop/src/main/__tests__/desktop-transcript-range-store.test.ts b/apps/desktop/src/main/__tests__/desktop-transcript-range-store.test.ts
index 308b9dce42..fa8cb4a3fc 100644
--- a/apps/desktop/src/main/__tests__/desktop-transcript-range-store.test.ts
+++ b/apps/desktop/src/main/__tests__/desktop-transcript-range-store.test.ts
@@ -582,5 +582,6 @@ function continuitySnapshot() {
       followup: [],
     },
     interactions: { pending: [] },
+    rootTurnSourceMessageIds: [],
   };
 }
diff --git a/apps/desktop/src/main/__tests__/permission-response-ipc-boundary.test.ts b/apps/desktop/src/main/__tests__/permission-response-ipc-boundary.test.ts
index bbc6bbad36..e5c6a2585f 100644
--- a/apps/desktop/src/main/__tests__/permission-response-ipc-boundary.test.ts
+++ b/apps/desktop/src/main/__tests__/permission-response-ipc-boundary.test.ts
@@ -251,9 +251,14 @@ describe('permission response IPC boundary', () => {
       normalizeStopSessionInput({
         source: 'stop_button',
         expectedTurnId: 'turn-workhub',
+        expectedAdmissionId: 'side-admission',
         extra: true,
       }),
-      { source: 'stop_button', expectedTurnId: 'turn-workhub' },
+      {
+        source: 'stop_button',
+        expectedTurnId: 'turn-workhub',
+        expectedAdmissionId: 'side-admission',
+      },
     );
     assert.throws(() => normalizeStopSessionInput(null), /stop session input/);
     assert.throws(() => normalizeStopSessionInput({ source: 'toolbar' }), /stop session source/);
@@ -261,5 +266,9 @@ describe('permission response IPC boundary', () => {
       () => normalizeStopSessionInput({ expectedTurnId: '' }),
       /expectedTurnId/,
     );
+    assert.throws(
+      () => normalizeStopSessionInput({ expectedAdmissionId: '' }),
+      /expectedAdmissionId/,
+    );
   });
 });
diff --git a/apps/desktop/src/main/__tests__/quote-companion-disposal.test.ts b/apps/desktop/src/main/__tests__/quote-companion-disposal.test.ts
index 8553509e2d..262600e919 100644
--- a/apps/desktop/src/main/__tests__/quote-companion-disposal.test.ts
+++ b/apps/desktop/src/main/__tests__/quote-companion-disposal.test.ts
@@ -121,7 +121,7 @@ describe('quote companion disposal fencing', () => {
       ...defaults.sideChat,
       send: async () => {
         sends += 1;
-        return { ok: true as const };
+        return { ok: true as const, turnId: 'side-chat-turn' };
       },
     };
 
@@ -140,7 +140,7 @@ describe('quote companion disposal fencing', () => {
   });
 
   it('does not consume quotes or report success when disposal wins the send race', async () => {
-    const pendingSend = deferred<{ ok: true }>();
+    const pendingSend = deferred<{ ok: true; turnId: string }>();
     let disposed = false;
     let consumed = 0;
     const defaults = createFakeWorkbarServices();
@@ -158,7 +158,7 @@ describe('quote companion disposal fencing', () => {
     );
 
     disposed = true;
-    pendingSend.resolve({ ok: true });
+    pendingSend.resolve({ ok: true, turnId: 'side-chat-turn' });
 
     assert.deepEqual(await turn, { status: 'disposed' });
     assert.equal(consumed, 0);
@@ -179,7 +179,7 @@ describe('quote companion disposal fencing', () => {
       },
       send: async () => {
         sends += 1;
-        return { ok: true as const };
+        return { ok: true as const, turnId: 'side-chat-turn' };
       },
     };
     const turn = performCompanionTurn(
diff --git a/apps/desktop/src/main/__tests__/quote-companion-retry.test.ts b/apps/desktop/src/main/__tests__/quote-companion-retry.test.ts
index 4070741470..c92153b392 100644
--- a/apps/desktop/src/main/__tests__/quote-companion-retry.test.ts
+++ b/apps/desktop/src/main/__tests__/quote-companion-retry.test.ts
@@ -22,6 +22,7 @@ import { afterEach, test } from 'node:test';
 import { parseHTML } from 'linkedom';
 import { act, createElement } from 'react';
 import { createRoot, type Root } from 'react-dom/client';
+import type { SessionEvent } from '@maka/core/events';
 import type { SessionChangedEvent, SessionSummary, TurnRecord } from '@maka/core/session';
 import {
   createFakeWorkbarServices,
@@ -44,18 +45,69 @@ const originalGlobals = {
 let mountedRoot: Root | undefined;
 const SOURCE_SESSION = session('source-session');
 
-afterEach(async () => {
-  if (mountedRoot) {
-    await act(async () => {
-      mountedRoot?.unmount();
-      await Promise.resolve();
-    });
-  }
-  mountedRoot = undefined;
-  Object.assign(globalThis, originalGlobals);
-});
+function deferred<T>() {
+  let resolve!: (value: T) => void;
+  let reject!: (reason?: unknown) => void;
+  const promise = new Promise<T>((settle, fail) => {
+    resolve = settle;
+    reject = fail;
+  });
+  return { promise, reject, resolve };
+}
 
-test('retries a busy Side Conversation at the newest settled boundary and clears its banner', async () => {
+type QueueUpdate = Extract<SessionEvent, { type: 'queue_update' }>;
+type QueueEntry = NonNullable<QueueUpdate['steeringEntries']>[number];
+
+function completeEvent(id: string, turnId: string, ts: number): SessionEvent {
+  return { type: 'complete', id, turnId, ts, stopReason: 'end_turn' };
+}
+
+function textDeltaEvent(id: string, turnId: string, ts: number, text: string): SessionEvent {
+  return { type: 'text_delta', id, messageId: 'assistant-message', turnId, ts, text };
+}
+
+function queueUpdateEvent(
+  id: string,
+  turnId: string,
+  ts: number,
+  steeringEntries: readonly QueueEntry[] = [],
+  followupEntries: readonly QueueEntry[] = [],
+): QueueUpdate {
+  return {
+    type: 'queue_update',
+    id,
+    turnId,
+    ts,
+    queueRevision: 1,
+    steering: steeringEntries.map((entry) => entry.content.text),
+    followup: followupEntries.map((entry) => entry.content.text),
+    steeringEntries: [...steeringEntries],
+    followupEntries: [...followupEntries],
+  };
+}
+
+function messageAdmittedEvent(
+  id: string,
+  turnId: string,
+  ts: number,
+  messageId: string,
+): SessionEvent {
+  return { type: 'message_admission', id, messageId, turnId, ts, outcome: 'admitted' };
+}
+
+function recoverableErrorEvent(id: string, turnId: string, ts: number): SessionEvent {
+  return {
+    type: 'error',
+    id,
+    turnId,
+    ts,
+    recoverable: true,
+    reason: 'connection_closed',
+    message: 'connection closed',
+  };
+}
+
+function installDom() {
   const parsed = parseHTML('<html><body><div id="root"></div></body></html>');
   const { document, window } = parsed;
   Object.assign(globalThis, {
@@ -67,16 +119,110 @@ test('retries a busy Side Conversation at the newest settled boundary and clears
     Node: window.Node,
     IS_REACT_ACT_ENVIRONMENT: true,
   });
+  const container = document.querySelector('#root');
+  assert.ok(container);
+  return container;
+}
 
-  let listCount = 0;
-  let sessionChange: ((event: SessionChangedEvent) => void) | undefined;
-  let releaseRetry: (() => void) | undefined;
-  const branchInputs: Array<{ sourceTurnId: string; copyId: string }> = [];
+async function renderProbe(
+  sideChat: Partial<WorkbarServices['sideChat']>,
+  options: {
+    ownership?: boolean;
+    sourceSession?: SessionSummary;
+    ready?: (container: Element) => boolean;
+    onSend?: (send: (text: string) => Promise<boolean>) => void;
+    onSteer?: (steer: (text: string) => Promise<boolean>) => void;
+    onStop?: (stop: () => Promise<void>) => void;
+  } = {},
+) {
+  const container = installDom();
   const defaults = createFakeWorkbarServices();
   const services: WorkbarServices = {
     ...defaults,
     sideChat: {
       ...defaults.sideChat,
+      listTurns: async () => [settledTurn('source-turn')],
+      branchFromTurn: async () => ({ ok: true as const, session: session('side-conversation') }),
+      ...sideChat,
+    },
+  };
+  const root = createRoot(container);
+  mountedRoot = root;
+  const children = options.ownership
+    ? createElement(QuoteCompanionOwnershipProbe, {
+        onSend: options.onSend ?? (() => undefined),
+        onSteer: options.onSteer,
+        onStop: options.onStop,
+      })
+    : createElement(QuoteCompanionProbe, { sourceSession: options.sourceSession });
+
+  await act(async () => {
+    root.render(createElement(WorkbarServicesProvider, { services, children }));
+    await Promise.resolve();
+  });
+  await waitUntil(
+    () =>
+      options.ready?.(container) ??
+      container.firstElementChild?.getAttribute('data-companion-id') === 'side-conversation',
+  );
+  return { container, root, services };
+}
+
+async function renderOwnershipProbe(sideChat: Partial<WorkbarServices['sideChat']>) {
+  let send!: (text: string) => Promise<boolean>;
+  let steer!: (text: string) => Promise<boolean>;
+  let stop!: () => Promise<void>;
+  let eventHandler: ((event: SessionEvent) => void) | undefined;
+  const subscribeEvents = sideChat.subscribeEvents;
+  const rendered = await renderProbe(
+    {
+      ...sideChat,
+      subscribeEvents: (sessionId, handler, onSeeded, onSeedError) => {
+        eventHandler = handler;
+        if (subscribeEvents) {
+          return subscribeEvents(sessionId, handler, onSeeded, onSeedError);
+        }
+        onSeeded?.();
+        return () => undefined;
+      },
+    },
+    {
+      ownership: true,
+      onSend: (value) => (send = value),
+      onSteer: (value) => (steer = value),
+      onStop: (value) => (stop = value),
+    },
+  );
+  return {
+    ...rendered,
+    send: (text: string) => send(text),
+    steer: (text: string) => steer(text),
+    stop: () => stop(),
+    emit(event: SessionEvent) {
+      assert.ok(eventHandler);
+      eventHandler(event);
+    },
+  };
+}
+
+afterEach(async () => {
+  if (mountedRoot) {
+    await act(async () => {
+      mountedRoot?.unmount();
+      await Promise.resolve();
+    });
+  }
+  mountedRoot = undefined;
+  Object.assign(globalThis, originalGlobals);
+});
+
+test('retries a busy Side Conversation at the newest settled boundary and clears its banner', async () => {
+  let listCount = 0;
+  let sessionChange: ((event: SessionChangedEvent) => void) | undefined;
+  let releaseRetry: (() => void) | undefined;
+  const branchInputs: Array<{ sourceTurnId: string; copyId: string }> = [];
+  const { container } = await renderProbe(
+    {
       listTurns: async () => {
         listCount += 1;
         return listCount === 1
@@ -100,22 +246,8 @@ test('retries a busy Side Conversation at the newest settled boundary and clears
         };
       },
     },
-  };
-  const container = document.querySelector('#root');
-  assert.ok(container);
-  const root = createRoot(container);
-  mountedRoot = root;
-
-  await act(async () => {
-    root.render(
-      createElement(WorkbarServicesProvider, {
-        services,
-        children: createElement(QuoteCompanionProbe),
-      }),
-    );
-    await Promise.resolve();
-  });
-  await waitUntil(() => branchInputs.length === 1 && sessionChange !== undefined);
+    { ready: () => branchInputs.length === 1 && sessionChange !== undefined },
+  );
   assert.match(container.textContent, /main conversation or a linked task is still running/i);
   const probe = container.firstElementChild;
   assert.ok(probe);
@@ -152,24 +284,9 @@ test('retries a busy Side Conversation at the newest settled boundary and clears
 });
 
 test('does not restart foreground setup when the source Session object refreshes', async () => {
-  const parsed = parseHTML('<html><body><div id="root"></div></body></html>');
-  const { document, window } = parsed;
-  Object.assign(globalThis, {
-    document,
-    window,
-    HTMLElement: window.HTMLElement,
-    HTMLIFrameElement: window.HTMLIFrameElement ?? class HTMLIFrameElement {},
-    Event: window.Event,
-    Node: window.Node,
-    IS_REACT_ACT_ENVIRONMENT: true,
-  });
-
   let branchCount = 0;
-  const defaults = createFakeWorkbarServices();
-  const services: WorkbarServices = {
-    ...defaults,
-    sideChat: {
-      ...defaults.sideChat,
+  const { container, root, services } = await renderProbe(
+    {
       listTurns: async () => [settledTurn('settled-turn')],
       branchFromTurn: async () => {
         branchCount += 1;
@@ -179,37 +296,676 @@ test('does not restart foreground setup when the source Session object refreshes
         return await new Promise<never>(() => undefined);
       },
     },
-  };
-  const container = document.querySelector('#root');
-  assert.ok(container);
-  const root = createRoot(container);
-  mountedRoot = root;
+    { sourceSession: session('source-session'), ready: () => branchCount === 1 },
+  );
+  const probe = container.firstElementChild;
+  assert.ok(probe);
+  await waitUntil(
+    () => branchCount === 1 && probe.getAttribute('data-preparing') === 'false',
+  );
 
-  const render = (sourceSession: SessionSummary) =>
+  await act(async () => {
     root.render(
       createElement(WorkbarServicesProvider, {
         services,
-        children: createElement(QuoteCompanionProbe, { sourceSession }),
+        children: createElement(QuoteCompanionProbe, {
+          sourceSession: session('source-session'),
+        }),
       }),
     );
+    await Promise.resolve();
+  });
+
+  assert.equal(branchCount, 1);
+  assert.equal(probe.getAttribute('data-preparing'), 'false');
+});
+
+test('keeps Side Conversation events owned by the Host-admitted turn across an admission race', async () => {
+  const pendingSend = deferred<{ ok: true; turnId: string }>();
+  const { container, emit, send } = await renderOwnershipProbe({
+    send: async () => pendingSend.promise,
+  });
+
+  let sendResult!: Promise<boolean>;
+  await act(async () => {
+    sendResult = send('new prompt');
+    await Promise.resolve();
+  });
+
+  await act(async () => {
+    emit(completeEvent('late-old-terminal', 'old-turn', 1));
+    await Promise.resolve();
+  });
+  assert.equal(container.firstElementChild?.getAttribute('data-processing'), 'true');
+
+  await act(async () => {
+    emit(textDeltaEvent('new-text-before-response', 'host-admitted-turn', 2, 'answer'));
+    await Promise.resolve();
+  });
+  assert.equal(container.firstElementChild?.getAttribute('data-processing'), 'true');
+
+  await act(async () => {
+    pendingSend.resolve({ ok: true, turnId: 'host-admitted-turn' });
+    assert.equal(await sendResult, true);
+    await Promise.resolve();
+  });
+
+  const probe = container.firstElementChild;
+  assert.ok(probe);
+  assert.equal(probe.getAttribute('data-live-turn-id'), 'host-admitted-turn');
+  assert.equal(probe.getAttribute('data-live-text'), 'answer');
+  assert.equal(probe.getAttribute('data-streaming'), 'true');
+  assert.equal(probe.getAttribute('data-processing'), 'false');
+});
+
+test('binds a busy-raced Side Conversation send through its Host-admitted message identity', async () => {
+  let admissionId: string | undefined;
+  const pendingSend = deferred<{
+    ok: true;
+    steered: true;
+    turnId: string;
+    messageId: string;
+  }>();
+  const { container, emit, send } = await renderOwnershipProbe({
+    send: async (_sessionId, command) => {
+      admissionId = command.turnId;
+      return pendingSend.promise;
+    },
+  });
+
+  let sendResult!: Promise<boolean>;
+  await act(async () => {
+    sendResult = send('steer the active turn');
+    await Promise.resolve();
+  });
+  await act(async () => {
+    emit(completeEvent('late-old-terminal', 'old-turn', 1));
+    emit(
+      queueUpdateEvent('accepted-queue', 'host-active-turn', 2, [
+        {
+          entryId: 'accepted-entry',
+          messageId: admissionId as string,
+          content: { text: 'steer the active turn' },
+          placement: 'current_turn',
+          state: 'queued',
+        },
+      ]),
+    );
+    await Promise.resolve();
+  });
+  assert.equal(container.firstElementChild?.getAttribute('data-processing'), 'true');
+  assert.notEqual(
+    container.firstElementChild?.getAttribute('data-live-turn-id'),
+    'host-active-turn',
+  );
+
+  await act(async () => {
+    pendingSend.resolve({
+      ok: true,
+      steered: true,
+      turnId: 'requested-turn-is-not-the-owner',
+      messageId: admissionId as string,
+    });
+    assert.equal(await sendResult, true);
+    await Promise.resolve();
+  });
+  assert.notEqual(
+    container.firstElementChild?.getAttribute('data-live-turn-id'),
+    'host-active-turn',
+  );
+  await act(async () => {
+    emit(
+      messageAdmittedEvent(
+        'accepted-admission',
+        'host-active-turn',
+        2.5,
+        admissionId as string,
+      ),
+    );
+    emit(textDeltaEvent('accepted-text', 'host-active-turn', 3, 'answer after steering'));
+    await Promise.resolve();
+  });
+
+  const probe = container.firstElementChild;
+  assert.ok(probe);
+  assert.equal(probe.getAttribute('data-live-turn-id'), 'host-active-turn');
+  assert.equal(probe.getAttribute('data-live-text'), 'answer after steering');
+  assert.equal(probe.getAttribute('data-streaming'), 'true');
+  assert.equal(probe.getAttribute('data-processing'), 'false');
+});
+
+test('replays queued Side Conversation text after Host assigns the ticket to a successor Turn', async () => {
+  let admissionId: string | undefined;
+  const pendingSend = deferred<{
+    ok: false;
+    reason: 'outcome_unknown';
+    messageId: string;
+  }>();
+  const { container, emit, send } = await renderOwnershipProbe({
+    send: async (_sessionId, command) => {
+      admissionId = command.turnId;
+      return pendingSend.promise;
+    },
+  });
+
+  let sendResult!: Promise<boolean>;
+  await act(async () => {
+    sendResult = send('continue in the successor turn');
+    await Promise.resolve();
+  });
+  await act(async () => {
+    emit(
+      messageAdmittedEvent(
+        'successor-admission',
+        'successor-root',
+        1,
+        admissionId as string,
+      ),
+    );
+    emit(queueUpdateEvent('successor-queue', 'successor-root', 2));
+    emit(textDeltaEvent('successor-text', 'successor-root', 3, 'answer from successor'));
+    await Promise.resolve();
+  });
 
   await act(async () => {
-    render(session('source-session'));
+    pendingSend.resolve({
+      ok: false,
+      reason: 'outcome_unknown',
+      messageId: admissionId as string,
+    });
+    assert.equal(await sendResult, true);
     await Promise.resolve();
   });
+
   const probe = container.firstElementChild;
   assert.ok(probe);
+  assert.equal(probe.getAttribute('data-live-turn-id'), 'successor-root');
+  assert.equal(probe.getAttribute('data-live-text'), 'answer from successor');
+  assert.equal(probe.getAttribute('data-processing'), 'false');
+});
+
+test('clears a stopped Side Conversation admission when its live retraction is lost', async () => {
+  let admissionId: string | undefined;
+  const pendingStop = deferred<{ kind: 'retracted'; messageId: string }>();
+  const pendingSend = deferred<{
+    ok: true;
+    steered: true;
+    turnId: string;
+    messageId: string;
+  }>();
+  const { container, send, stop } = await renderOwnershipProbe({
+    send: async (_sessionId, command) => {
+      admissionId = command.turnId;
+      return pendingSend.promise;
+    },
+    stop: async (_sessionId, expectedAdmissionId) => {
+      assert.equal(expectedAdmissionId, admissionId);
+      return pendingStop.promise;
+    },
+  });
+
+  let sendResult!: Promise<boolean>;
+  await act(async () => {
+    sendResult = send('stop this queued send');
+    await Promise.resolve();
+  });
+  let stopResult!: Promise<void>;
+  await act(async () => {
+    stopResult = stop();
+    await Promise.resolve();
+  });
+  assert.equal(container.firstElementChild?.getAttribute('data-processing'), 'true');
+
+  await act(async () => {
+    pendingStop.resolve({ kind: 'retracted', messageId: admissionId as string });
+    await stopResult;
+    await Promise.resolve();
+  });
+  assert.equal(container.firstElementChild?.getAttribute('data-processing'), 'false');
+
+  await act(async () => {
+    pendingSend.resolve({
+      ok: true,
+      steered: true,
+      turnId: 'old-turn',
+      messageId: admissionId as string,
+    });
+    assert.equal(await sendResult, false);
+    await Promise.resolve();
+  });
+  assert.equal(container.firstElementChild?.getAttribute('data-processing'), 'false');
+  assert.equal(container.firstElementChild?.getAttribute('data-live-turn-id'), '');
+});
+
+test('keeps a Side Conversation admission when Host stop outcome is unknown', async () => {
+  let admissionId: string | undefined;
+  const pendingStop = deferred<undefined>();
+  const { container, emit, send, stop } = await renderOwnershipProbe({
+    send: async (_sessionId, command) => {
+      admissionId = command.turnId;
+      return {
+        ok: false as const,
+        reason: 'outcome_unknown' as const,
+        messageId: admissionId as string,
+      };
+    },
+    stop: async () => pendingStop.promise,
+  });
+
+  await act(async () => {
+    assert.equal(await send('keep this admission'), true);
+    await Promise.resolve();
+  });
+  let stopResult!: Promise<void>;
+  await act(async () => {
+    stopResult = stop();
+    await Promise.resolve();
+  });
+  await act(async () => {
+    emit(
+      messageAdmittedEvent(
+        'admitted-during-unknown-stop',
+        'admitted-after-unknown-stop',
+        1,
+        admissionId as string,
+      ),
+    );
+    emit(
+      textDeltaEvent(
+        'text-during-unknown-stop',
+        'admitted-after-unknown-stop',
+        2,
+        'answer',
+      ),
+    );
+    await Promise.resolve();
+  });
+  await act(async () => {
+    pendingStop.reject(new Error('Host stop result is unknown'));
+    await stopResult;
+    await Promise.resolve();
+  });
   await waitUntil(
-    () => branchCount === 1 && probe.getAttribute('data-preparing') === 'false',
+    () =>
+      container.firstElementChild?.getAttribute('data-live-turn-id') ===
+      'admitted-after-unknown-stop',
   );
+  assert.equal(
+    container.firstElementChild?.getAttribute('data-live-turn-id'),
+    'admitted-after-unknown-stop',
+  );
+  assert.equal(container.firstElementChild?.getAttribute('data-live-text'), 'answer');
+  assert.equal(container.firstElementChild?.getAttribute('data-streaming'), 'true');
+  assert.equal(container.firstElementChild?.getAttribute('data-processing'), 'false');
+});
 
+test('stops a bound Side Conversation by its exact Host Turn identity', async () => {
+  let stoppedAdmissionId: string | undefined;
+  const { send, stop } = await renderOwnershipProbe({
+    send: async () => ({ ok: true as const, turnId: 'host-turn-1' }),
+    stop: async (_sessionId, admissionId) => {
+      stoppedAdmissionId = admissionId;
+    },
+  });
+  await act(async () => {
+    assert.equal(await send('start this exact turn'), true);
+    await Promise.resolve();
+  });
   await act(async () => {
-    render(session('source-session'));
+    await stop();
     await Promise.resolve();
   });
+  assert.equal(stoppedAdmissionId, 'host-turn-1');
+});
 
-  assert.equal(branchCount, 1);
-  assert.equal(probe.getAttribute('data-preparing'), 'false');
+test('releases a queued Side Conversation admission from the Host queue retract', async () => {
+  let admissionId: string | undefined;
+  const pendingSend = deferred<{
+    ok: true;
+    steered: true;
+    turnId: string;
+    messageId: string;
+  }>();
+  const { container, emit, send } = await renderOwnershipProbe({
+    send: async (_sessionId, command) => {
+      admissionId = command.turnId;
+      return pendingSend.promise;
+    },
+  });
+
+  let sendResult!: Promise<boolean>;
+  await act(async () => {
+    sendResult = send('retract this queued send');
+    await Promise.resolve();
+  });
+  assert.equal(container.firstElementChild?.getAttribute('data-processing'), 'true');
+
+  await act(async () => {
+    emit({
+      type: 'message_admission',
+      id: 'retracted-admission',
+      turnId: 'old-turn',
+      ts: 1,
+      messageId: admissionId as string,
+      outcome: 'retracted',
+    });
+    await Promise.resolve();
+  });
+  assert.equal(container.firstElementChild?.getAttribute('data-processing'), 'false');
+
+  await act(async () => {
+    pendingSend.resolve({
+      ok: true,
+      steered: true,
+      turnId: 'not-the-owner',
+      messageId: admissionId as string,
+    });
+    assert.equal(await sendResult, false);
+    await Promise.resolve();
+  });
+  assert.equal(container.firstElementChild?.getAttribute('data-processing'), 'false');
+});
+
+test('keeps the same Side Conversation admission across a recoverable subscription error', async () => {
+  let subscriptionCount = 0;
+  const pendingSend = deferred<{ ok: true; turnId: string }>();
+  const { container, emit, send } = await renderOwnershipProbe({
+    subscribeEvents: (_sessionId, _handler, onSeeded) => {
+      subscriptionCount += 1;
+      onSeeded?.();
+      return () => undefined;
+    },
+    send: async () => pendingSend.promise,
+  });
+  assert.equal(subscriptionCount, 1);
+
+  let sendResult!: Promise<boolean>;
+  await act(async () => {
+    sendResult = send('survive a recoverable stream error');
+    await Promise.resolve();
+  });
+  await waitUntil(() => container.firstElementChild?.getAttribute('data-processing') === 'true');
+  await act(async () => {
+    emit(recoverableErrorEvent('recoverable-subscription-error', 'old-turn', 1));
+    await Promise.resolve();
+  });
+  assert.equal(container.firstElementChild?.getAttribute('data-processing'), 'true');
+  assert.equal(subscriptionCount, 1);
+
+  await act(async () => {
+    pendingSend.resolve({ ok: true, turnId: 'late-turn' });
+    assert.equal(await sendResult, true);
+    await Promise.resolve();
+  });
+  await act(async () => {
+    emit(completeEvent('late-complete', 'late-turn', 2));
+    await Promise.resolve();
+  });
+  await waitUntil(() => container.firstElementChild?.getAttribute('data-processing') === 'false');
+});
+
+test('keeps the active Side Conversation streaming when Stop retracts a queued steer', async () => {
+  const pendingSteer = deferred<{ kind: 'queued'; messageId: string }>();
+  let admissionId: string | undefined;
+  let steerCalls = 0;
+  const { container, emit, send, steer, stop } = await renderOwnershipProbe({
+    send: async () => ({ ok: true as const, turnId: 'old-turn' }),
+    steer: async (_sessionId, _text, requestedAdmissionId) => {
+      steerCalls += 1;
+      admissionId = requestedAdmissionId;
+      return pendingSteer.promise;
+    },
+    stop: async () => undefined,
+  });
+
+  await act(async () => {
+    assert.equal(await send('initial prompt'), true);
+    await Promise.resolve();
+  });
+  await waitUntil(() => container.firstElementChild?.getAttribute('data-streaming') === 'true');
+  let steerResult!: Promise<boolean>;
+  await act(async () => {
+    steerResult = steer('queue this steer');
+    await Promise.resolve();
+  });
+  await waitUntil(() => steerCalls === 1);
+  assert.ok(admissionId);
+  await act(async () => {
+    await stop();
+    await Promise.resolve();
+  });
+  assert.equal(container.firstElementChild?.getAttribute('data-live-turn-id'), 'old-turn');
+  assert.equal(container.firstElementChild?.getAttribute('data-streaming'), 'true');
+
+  await act(async () => {
+    emit({
+      type: 'message_admission',
+      id: 'queued-steer-retracted',
+      turnId: 'old-turn',
+      ts: 1,
+      messageId: admissionId as string,
+      outcome: 'retracted',
+    });
+    await Promise.resolve();
+  });
+  assert.equal(container.firstElementChild?.getAttribute('data-streaming'), 'true');
+
+  await act(async () => {
+    pendingSteer.resolve({ kind: 'queued', messageId: admissionId as string });
+    assert.equal(await steerResult, false);
+    await Promise.resolve();
+  });
+});
+
+test('stops the active Side Conversation after retracting its queued steer', async () => {
+  const pendingSteer = deferred<{ kind: 'queued'; messageId: string }>();
+  let admissionId: string | undefined;
+  const stoppedIds: Array<string | undefined> = [];
+  const { send, steer, stop } = await renderOwnershipProbe({
+    send: async () => ({ ok: true as const, turnId: 'old-turn' }),
+    steer: async (_sessionId, _text, requestedAdmissionId) => {
+      admissionId = requestedAdmissionId;
+      return pendingSteer.promise;
+    },
+    stop: async (_sessionId, expectedId) => {
+      stoppedIds.push(expectedId);
+      return expectedId && expectedId === admissionId
+        ? { kind: 'retracted' as const, messageId: expectedId }
+        : undefined;
+    },
+  });
+
+  await act(async () => {
+    assert.equal(await send('initial prompt'), true);
+    await Promise.resolve();
+  });
+  let steerResult!: Promise<boolean>;
+  await act(async () => {
+    steerResult = steer('queue this steer');
+    await Promise.resolve();
+  });
+  await waitUntil(() => admissionId !== undefined);
+  await act(async () => {
+    await stop();
+    await Promise.resolve();
+  });
+  await act(async () => {
+    await stop();
+    await Promise.resolve();
+  });
+
+  assert.deepEqual(stoppedIds, [admissionId, 'old-turn']);
+  await act(async () => {
+    pendingSteer.resolve({ kind: 'queued', messageId: admissionId as string });
+    assert.equal(await steerResult, false);
+    await Promise.resolve();
+  });
+});
+
+test('does not let an older Stop failure release a newer active Turn Stop', async () => {
+  const pendingSteer = deferred<{ kind: 'queued'; messageId: string }>();
+  const queuedStop = deferred<undefined>();
+  const activeStop = deferred<undefined>();
+  let admissionId: string | undefined;
+  const stoppedIds: Array<string | undefined> = [];
+  const { emit, send, steer, stop } = await renderOwnershipProbe({
+    send: async () => ({ ok: true as const, turnId: 'old-turn' }),
+    steer: async (_sessionId, _text, requestedAdmissionId) => {
+      admissionId = requestedAdmissionId;
+      return pendingSteer.promise;
+    },
+    stop: async (_sessionId, expectedId) => {
+      stoppedIds.push(expectedId);
+      return stoppedIds.length === 1 ? queuedStop.promise : activeStop.promise;
+    },
+  });
+
+  await act(async () => {
+    assert.equal(await send('initial prompt'), true);
+    await Promise.resolve();
+  });
+  let steerResult!: Promise<boolean>;
+  await act(async () => {
+    steerResult = steer('queue this steer');
+    await Promise.resolve();
+  });
+  await waitUntil(() => admissionId !== undefined);
+  const queuedStopResult = stop();
+  await act(async () => {
+    emit({
+      type: 'message_admission',
+      id: 'queued-steer-retracted-before-stop-reply',
+      turnId: 'old-turn',
+      ts: 1,
+      messageId: admissionId as string,
+      outcome: 'retracted',
+    });
+    await Promise.resolve();
+  });
+  const activeStopResult = stop();
+  await act(async () => {
+    queuedStop.reject(new Error('old Stop reply was lost'));
+    await queuedStopResult;
+    await Promise.resolve();
+  });
+  const duplicateStopResult = stop();
+  await Promise.resolve();
+
+  assert.deepEqual(stoppedIds, [admissionId, 'old-turn']);
+  activeStop.resolve(undefined);
+  await Promise.all([activeStopResult, duplicateStopResult]);
+  await act(async () => {
+    pendingSteer.resolve({ kind: 'queued', messageId: admissionId as string });
+    assert.equal(await steerResult, false);
+    await Promise.resolve();
+  });
+});
+
+test('continues projecting the active Turn while a steer awaits Host admission', async () => {
+  const pendingSteer = deferred<{ kind: 'queued'; messageId: string }>();
+  let admissionId: string | undefined;
+  const { container, emit, send, steer } = await renderOwnershipProbe({
+    send: async () => ({ ok: true as const, turnId: 'old-turn' }),
+    steer: async (_sessionId, _text, requestedAdmissionId) => {
+      admissionId = requestedAdmissionId;
+      return pendingSteer.promise;
+    },
+  });
+
+  await act(async () => {
+    assert.equal(await send('initial prompt'), true);
+    await Promise.resolve();
+  });
+  let steerResult!: Promise<boolean>;
+  await act(async () => {
+    steerResult = steer('queue this steer');
+    await Promise.resolve();
+  });
+  await waitUntil(() => admissionId !== undefined);
+  await act(async () => {
+    emit(textDeltaEvent('old-turn-text', 'old-turn', 1, 'still streaming'));
+    await Promise.resolve();
+  });
+
+  assert.equal(container.firstElementChild?.getAttribute('data-live-turn-id'), 'old-turn');
+  assert.equal(container.firstElementChild?.getAttribute('data-live-text'), 'still streaming');
+  assert.equal(container.firstElementChild?.getAttribute('data-streaming'), 'true');
+
+  await act(async () => {
+    pendingSteer.resolve({ kind: 'queued', messageId: admissionId as string });
+    assert.equal(await steerResult, true);
+    await Promise.resolve();
+  });
+});
+
+test('fails a send when observation seed rejects and resubscribes for retry', async () => {
+  let sendCalls = 0;
+  let subscriptionCount = 0;
+  let rejectSeed: ((error: unknown) => void) | undefined;
+  let markSeeded: (() => void) | undefined;
+  const { send } = await renderOwnershipProbe({
+    subscribeEvents: (_sessionId, _handler, onSeeded, onSeedError) => {
+      subscriptionCount += 1;
+      if (subscriptionCount === 1) rejectSeed = onSeedError;
+      else markSeeded = onSeeded;
+      return () => undefined;
+    },
+    send: async () => {
+      sendCalls += 1;
+      return { ok: true as const, turnId: 'retry-turn' };
+    },
+  });
+  assert.ok(rejectSeed);
+
+  let failedResult!: Promise<boolean>;
+  await act(async () => {
+    failedResult = send('observer failure');
+    rejectSeed?.(new Error('observer failed'));
+    assert.equal(await failedResult, false);
+  });
+  assert.equal(sendCalls, 0);
+  assert.equal(subscriptionCount, 2);
+  assert.ok(markSeeded);
+
+  await act(async () => {
+    markSeeded?.();
+    await Promise.resolve();
+  });
+  let retryResult!: Promise<boolean>;
+  await act(async () => {
+    retryResult = send('retry after observer failure');
+    assert.equal(await retryResult, true);
+  });
+  assert.equal(sendCalls, 1);
+});
+
+test('releases a send waiting for observation when the Side Conversation is disposed', async () => {
+  let sendCalls = 0;
+  let unsubscribed = false;
+  const { root, send } = await renderOwnershipProbe({
+    subscribeEvents: () => () => {
+      unsubscribed = true;
+    },
+    send: async () => {
+      sendCalls += 1;
+      return { ok: true as const, turnId: 'disposed-turn' };
+    },
+  });
+
+  let sendResult!: Promise<boolean>;
+  await act(async () => {
+    sendResult = send('dispose while observing');
+    await Promise.resolve();
+  });
+  await act(async () => {
+    root.unmount();
+    await Promise.resolve();
+  });
+
+  assert.equal(await sendResult, false);
+  assert.equal(sendCalls, 0);
+  assert.equal(unsubscribed, true);
+  mountedRoot = undefined;
 });
 
 function QuoteCompanionProbe(props: { sourceSession?: SessionSummary }) {
@@ -227,6 +983,31 @@ function QuoteCompanionProbe(props: { sourceSession?: SessionSummary }) {
   }, companion.error);
 }
 
+function QuoteCompanionOwnershipProbe(props: {
+  onSend: (send: (text: string) => Promise<boolean>) => void;
+  onSteer?: (steer: (text: string) => Promise<boolean>) => void;
+  onStop?: (stop: () => Promise<void>) => void;
+}) {
+  const companion = useQuoteCompanion({
+    panelId: 'ownership-panel',
+    pendingQuotes: [],
+    sourceSession: SOURCE_SESSION,
+    locale: 'en',
+    onQuotesConsumed: () => undefined,
+  });
+  props.onSend(companion.send);
+  props.onSteer?.(companion.steer);
+  props.onStop?.(companion.stop);
+  return createElement('div', {
+    'data-companion-id': companion.companionSession?.id ?? '',
+    'data-error': companion.error ?? '',
+    'data-live-turn-id': companion.liveTurn?.turnId ?? '',
+    'data-live-text': companion.liveTurn?.steps.find((step) => step.text)?.text?.text ?? '',
+    'data-streaming': String(companion.streaming),
+    'data-processing': String(companion.processing),
+  });
+}
+
 function session(id: string): SessionSummary {
   return {
     id,
diff --git a/apps/desktop/src/main/__tests__/runtime-host-bot-session-adapter.test.ts b/apps/desktop/src/main/__tests__/runtime-host-bot-session-adapter.test.ts
index 6482a9a2bf..2dc9bd14ea 100644
--- a/apps/desktop/src/main/__tests__/runtime-host-bot-session-adapter.test.ts
+++ b/apps/desktop/src/main/__tests__/runtime-host-bot-session-adapter.test.ts
@@ -467,6 +467,7 @@ function continuitySnapshot(rootTurn: TurnSnapshot | null): SessionContinuitySna
     goal: null,
     queue: { hostEpoch: 'host-1', queueRevision: 0, steering: [], followup: [] },
     interactions: { pending: [] },
+    rootTurnSourceMessageIds: [],
   };
 }
 
diff --git a/apps/desktop/src/main/__tests__/runtime-host-client.test.ts b/apps/desktop/src/main/__tests__/runtime-host-client.test.ts
index 01fd41646e..748a679bc4 100644
--- a/apps/desktop/src/main/__tests__/runtime-host-client.test.ts
+++ b/apps/desktop/src/main/__tests__/runtime-host-client.test.ts
@@ -181,6 +181,7 @@ function subscription(
       goal: null,
       queue: { hostEpoch: 'host-1', queueRevision: 0, steering: [], followup: [] },
       interactions: { pending: [] },
+      rootTurnSourceMessageIds: [],
     },
     loadTranscript: async <T>(_decodeMessage: (value: unknown) => T) => {
       lifecycle.push(`${sessionId}:transcript`);
diff --git a/apps/desktop/src/main/__tests__/runtime-host-desktop-candidate.test.ts b/apps/desktop/src/main/__tests__/runtime-host-desktop-candidate.test.ts
index ea2d4b24b7..af1ab014cc 100644
--- a/apps/desktop/src/main/__tests__/runtime-host-desktop-candidate.test.ts
+++ b/apps/desktop/src/main/__tests__/runtime-host-desktop-candidate.test.ts
@@ -1119,6 +1119,7 @@ function continuitySnapshot(
       followup: [],
     },
     interactions: { pending: [] },
+    rootTurnSourceMessageIds: [],
     ...overrides,
   };
 }
diff --git a/apps/desktop/src/main/__tests__/runtime-host-session-execution-ipc-main.test.ts b/apps/desktop/src/main/__tests__/runtime-host-session-execution-ipc-main.test.ts
index 4514ea326b..708350c8f2 100644
--- a/apps/desktop/src/main/__tests__/runtime-host-session-execution-ipc-main.test.ts
+++ b/apps/desktop/src/main/__tests__/runtime-host-session-execution-ipc-main.test.ts
@@ -30,7 +30,10 @@ import {
   SESSION_CONTINUITY_SCHEMA_VERSION,
   type SessionCatalogProjection,
 } from "@maka/runtime-host/protocol";
-import { RuntimeHostOperationError } from '@maka/runtime-host/client';
+import {
+  RuntimeHostOperationError,
+  RuntimeHostRequestInterruptedError,
+} from '@maka/runtime-host/client';
 import { createAttachmentApprovalRegistry } from "../attachment-approval.js";
 import type { DesktopRuntimeHostSession } from "../runtime-host-client.js";
 import {
@@ -40,6 +43,13 @@ import {
 import { RuntimeHostSessionObserver } from "../runtime-host-session-observer.js";
 import { runtimeHostSessionFixture } from "./runtime-host-session-test-fixture.js";
 
+test('registers Session observation as one reconnectable operation', () => {
+  const ipc = ipcHarness();
+  registerExecutionIpc({ client: executionClient({}) }, ipc);
+
+  assert.equal(ipc.reconnectableChannels.has('sessions:observe'), true);
+});
+
 test("keeps synthetic E2E interactions visible through Host hydration and retires their answer", async () => {
   const observer = observerWithSnapshot();
   const ipc = ipcHarness();
@@ -627,6 +637,232 @@ test("queues a mid-turn send as steering when the Host reports the session busy"
   ]);
 });
 
+test("retries a dispatched normal send with its original Turn identity", async () => {
+  const starts: unknown[] = [];
+  let reconnectQueries = 0;
+  const ipc = ipcHarness();
+  registerExecutionIpc(
+    {
+      client: executionClient({
+        getSession: async () => {
+          reconnectQueries += 1;
+          return sideConversationSession();
+        },
+        startTurn: async (input) => {
+          starts.push(input);
+          if (starts.length === 1) {
+            throw new RuntimeHostRequestInterruptedError(
+              "turn.start",
+              "command",
+              "dispatched",
+              "connection_lost",
+            );
+          }
+          return {
+            kind: "started",
+            turn: {
+              sessionId: input.sessionId,
+              turnId: input.turnId,
+              runId: "run-1",
+              status: "running",
+            },
+            skillInvocation: { loaded: [], failed: [], receipts: [] },
+          };
+        },
+      }),
+      newId: () => "turn-1",
+    },
+    ipc,
+  );
+
+  const result = await ipc.invoke("sessions:send", "session-1", {
+    type: "send",
+    text: "keep this Turn identity",
+  });
+
+  assert.equal(reconnectQueries, 2, 'initial Session lookup plus reconnect probe');
+  assert.deepEqual(starts, [
+    {
+      sessionId: "session-1",
+      turnId: "turn-1",
+      content: { text: "keep this Turn identity", inlineReferences: [] },
+    },
+    {
+      sessionId: "session-1",
+      turnId: "turn-1",
+      content: { text: "keep this Turn identity", inlineReferences: [] },
+    },
+  ]);
+  assert.deepEqual(result, {
+    ok: true,
+    turnId: "turn-1",
+    attachments: [],
+    inlineReferences: [],
+    skillInvocation: { loaded: [], failed: [], receipts: [] },
+  });
+});
+
+test("does not add admission retry semantics to an ordinary send", async () => {
+  let starts = 0;
+  let sessionQueries = 0;
+  const ipc = ipcHarness();
+  registerExecutionIpc(
+    {
+      client: executionClient({
+        getSession: async () => {
+          sessionQueries += 1;
+          return session();
+        },
+        startTurn: async () => {
+          starts += 1;
+          throw new RuntimeHostRequestInterruptedError(
+            "turn.start",
+            "command",
+            "dispatched",
+            "connection_lost",
+          );
+        },
+      }),
+      newId: () => "turn-1",
+    },
+    ipc,
+  );
+
+  await assert.rejects(
+    ipc.invoke("sessions:send", "session-1", {
+      type: "send",
+      text: "preserve the ordinary send contract",
+    }),
+    RuntimeHostRequestInterruptedError,
+  );
+  assert.equal(starts, 1);
+  assert.equal(sessionQueries, 1, "only the initial Session lookup runs");
+});
+
+test("retries a dispatched busy fallback with its original message identity", async () => {
+  const submits: unknown[] = [];
+  let reconnectQueries = 0;
+  const ipc = ipcHarness();
+  registerExecutionIpc(
+    {
+      client: executionClient({
+        getSession: async (sessionId) => {
+          reconnectQueries += 1;
+          return sessionId === 'side-session'
+            ? sideConversationSession(sessionId)
+            : session();
+        },
+        startTurn: async () => {
+          throw new RuntimeHostOperationError(
+            "turn.start",
+            "session_busy",
+            "Session already has an active root Turn",
+          );
+        },
+        submitMessage: async (input) => {
+          submits.push(input);
+          if (
+            input.messageId === "turn-unknown" ||
+            input.content.text === "ordinary chat keeps the existing failure contract"
+          ) {
+            throw new RuntimeHostOperationError(
+              "turn.message.submit",
+              "outcome_unknown",
+              "Message disposition cannot be proven in this Host Epoch",
+            );
+          }
+          if (submits.length === 1) {
+            throw new RuntimeHostRequestInterruptedError(
+              "turn.message.submit",
+              "command",
+              "dispatched",
+              "connection_lost",
+            );
+          }
+          return { disposition: "steering", queueRevision: 1 };
+        },
+      }),
+      newId: () => "id-1",
+    },
+    ipc,
+  );
+
+  const result = await ipc.invoke("sessions:send", "side-session", {
+    type: "send",
+    turnId: "turn-1",
+    text: "keep this message identity",
+  });
+
+  assert.equal(reconnectQueries, 2, 'initial Session lookup plus reconnect probe');
+  assert.deepEqual(submits, [
+    {
+      sessionId: "side-session",
+      messageId: "turn-1",
+      content: { text: "keep this message identity", inlineReferences: [] },
+      placement: "current_turn",
+    },
+    {
+      sessionId: "side-session",
+      messageId: "turn-1",
+      content: { text: "keep this message identity", inlineReferences: [] },
+      placement: "current_turn",
+    },
+  ]);
+  assert.deepEqual(result, {
+    ok: true,
+    steered: true,
+    turnId: "turn-1",
+    messageId: "turn-1",
+    attachments: [],
+    inlineReferences: [],
+    skillInvocation: { loaded: [], failed: [], receipts: [] },
+  });
+  await assert.rejects(
+    ipc.invoke("sessions:send", "session-1", {
+      type: "send",
+      turnId: "turn-unknown",
+      text: "ordinary chat keeps the existing failure contract",
+    }),
+    (error: unknown) =>
+      error instanceof RuntimeHostOperationError && error.code === 'outcome_unknown',
+  );
+  assert.deepEqual(
+    await ipc.invoke("sessions:send", "side-session", {
+      type: "send",
+      turnId: "turn-unknown",
+      text: "keep waiting for the Host outcome",
+    }),
+    {
+      ok: false,
+      reason: "outcome_unknown",
+      messageId: "turn-unknown",
+      skillInvocation: { loaded: [], failed: [], receipts: [] },
+    },
+  );
+});
+
+test("returns the Host-started Turn identity when a direct steer races idle", async () => {
+  const ipc = ipcHarness();
+  registerExecutionIpc(
+    {
+      client: executionClient({
+        getSession: async () => session(),
+        submitMessage: async () => ({
+          disposition: "turn_started",
+          turnId: "host-started-turn",
+        }),
+      }),
+      newId: () => "steer-message-id",
+    },
+    ipc,
+  );
+
+  assert.deepEqual(await ipc.invoke("sessions:steer", "session-1", "continue now"), {
+    kind: "started",
+    turnId: "host-started-turn",
+  });
+});
+
 test("starts the turn from the queued message when the busy race resolves idle", async () => {
   const changes: unknown[] = [];
   const submits: unknown[] = [];
@@ -920,11 +1156,19 @@ test("routes per-entry queue mutations to the Runtime Host", async () => {
 test("binds steer and stop to Host-owned queue and active Turn identities", async () => {
   const submits: unknown[] = [];
   const interrupts: unknown[] = [];
+  const retractions: unknown[] = [];
   const stopLifecycle: string[] = [];
   let sequence = 0;
   const client = executionClient({
     submitMessage: async (input) => {
       submits.push(input);
+      if (input.messageId === 'unknown-ticket') {
+        throw new RuntimeHostOperationError(
+          'turn.message.submit',
+          'outcome_unknown',
+          'Message disposition cannot be proven in this Host Epoch',
+        );
+      }
       return { disposition: "steering", queueRevision: 2 };
     },
     interruptTurn: async (input) => {
@@ -943,17 +1187,40 @@ test("binds steer and stop to Host-owned queue and active Turn identities", asyn
         },
       };
     },
+    retractQueueEntry: async (input) => {
+      retractions.push(input);
+      return { queueRevision: 3 };
+    },
+  });
+  const observer = observerWithSnapshot({
+    queue: {
+      hostEpoch: 'host-1',
+      queueRevision: 2,
+      steering: [
+        {
+          entryId: 'entry-1',
+          messageId: 'steer-ticket-1',
+          content: { text: 'Continue' },
+          placement: 'current_turn',
+          state: 'queued',
+        },
+        {
+          entryId: 'entry-2',
+          messageId: 'in-flight-ticket',
+          content: { text: 'Already accepted' },
+          placement: 'current_turn',
+          state: 'in_flight',
+        },
+      ],
+      followup: [],
+    },
+    rootTurnSourceMessageIds: ['successor-ticket'],
   });
-  const observer = observerWithSnapshot();
   const ipc = ipcHarness();
   registerExecutionIpc(
     {
       client,
       observer,
-      attachmentApprovals: createAttachmentApprovalRegistry(),
-      emitSessionsChanged() {},
-      stat: async () => ({ size: 0 }),
-      resizeImage: async (bytes) => bytes,
       beforeStop() {
         stopLifecycle.push("teardown");
       },
@@ -963,29 +1230,69 @@ test("binds steer and stop to Host-owned queue and active Turn identities", asyn
   );
 
   assert.deepEqual(
-    await ipc.invoke("sessions:steer", "session-1", "  Continue  "),
+    await ipc.invoke("sessions:steer", "session-1", "  Continue  ", "steer-ticket-1"),
     {
       kind: "queued",
+      messageId: "steer-ticket-1",
     },
   );
+  assert.deepEqual(
+    await ipc.invoke('sessions:steer', 'session-1', 'Continue', 'unknown-ticket'),
+    { kind: 'outcome_unknown', messageId: 'unknown-ticket' },
+  );
+  assert.deepEqual(
+    await ipc.invoke("sessions:stop", "session-1", {
+      source: "stop_button",
+      expectedAdmissionId: "steer-ticket-1",
+    }),
+    { kind: 'retracted', messageId: 'steer-ticket-1' },
+  );
+  assert.deepEqual(retractions, [
+    {
+      sessionId: 'session-1',
+      entryId: 'entry-1',
+      retractId: 'id-1',
+    },
+  ]);
+  assert.deepEqual(stopLifecycle, []);
+  for (const expectedAdmissionId of ['in-flight-ticket', 'successor-ticket']) {
+    await ipc.invoke('sessions:stop', 'session-1', {
+      source: 'stop_button',
+      expectedAdmissionId,
+    });
+  }
+  assert.deepEqual(stopLifecycle, ['teardown', 'interrupt', 'teardown', 'interrupt']);
   await ipc.invoke("sessions:stop", "session-1", {
     source: "stop_button",
     expectedTurnId: "turn-unrelated",
   });
-  assert.deepEqual(stopLifecycle, []);
+  assert.deepEqual(stopLifecycle, ['teardown', 'interrupt', 'teardown', 'interrupt']);
   await ipc.invoke("sessions:stop", "session-1", {
     source: "stop_button",
     expectedTurnId: "turn-1",
   });
-  assert.deepEqual(stopLifecycle, ["teardown", "interrupt"]);
+  assert.deepEqual(stopLifecycle, [
+    'teardown',
+    'interrupt',
+    'teardown',
+    'interrupt',
+    'teardown',
+    'interrupt',
+  ]);
 
   assert.deepEqual(submits, [
     {
       sessionId: "session-1",
-      messageId: "id-1",
+      messageId: "steer-ticket-1",
       content: { text: "Continue" },
       placement: "current_turn",
     },
+    {
+      sessionId: 'session-1',
+      messageId: 'unknown-ticket',
+      content: { text: 'Continue' },
+      placement: 'current_turn',
+    },
   ]);
   assert.deepEqual(interrupts, [
     {
@@ -994,6 +1301,18 @@ test("binds steer and stop to Host-owned queue and active Turn identities", asyn
       turnId: "turn-1",
       runId: "run-1",
     },
+    {
+      sessionId: 'session-1',
+      interruptId: 'id-3',
+      turnId: 'turn-1',
+      runId: 'run-1',
+    },
+    {
+      sessionId: 'session-1',
+      interruptId: 'id-4',
+      turnId: 'turn-1',
+      runId: 'run-1',
+    },
   ]);
   await observer.close();
 });
@@ -1041,12 +1360,15 @@ function unusedObserver(): RuntimeHostSessionObserver {
   });
 }
 
-function observerWithSnapshot(): RuntimeHostSessionObserver {
-  return observerWithTranscript([]);
+function observerWithSnapshot(
+  overrides: Partial<import('@maka/runtime-host/protocol').SessionContinuitySnapshot> = {},
+): RuntimeHostSessionObserver {
+  return observerWithTranscript([], overrides);
 }
 
 function observerWithTranscript(
   transcript: readonly import('@maka/core/session').StoredMessage[],
+  overrides: Partial<import('@maka/runtime-host/protocol').SessionContinuitySnapshot> = {},
 ): RuntimeHostSessionObserver {
   let finishEvents!: () => void;
   const eventsFinished = new Promise<void>((resolve) => {
@@ -1079,6 +1401,8 @@ function observerWithTranscript(
             followup: [],
           },
           interactions: { pending: [] },
+          rootTurnSourceMessageIds: [],
+          ...overrides,
         },
         activeAssistantStreams: [],
         transcript: Promise.resolve([...transcript]),
@@ -1100,15 +1424,24 @@ type IpcHandler = Parameters<Pick<IpcMain, "handle">["handle"]>[1];
 
 function ipcHarness() {
   const handlers = new Map<string, IpcHandler>();
+  const reconnectableChannels = new Set<string>();
   const sender = Object.assign(new EventEmitter(), { id: 9, send() {} });
+  const register = (channel: string, handler: IpcHandler) => {
+    assert.equal(
+      handlers.has(channel),
+      false,
+      `duplicate handler: ${channel}`,
+    );
+    handlers.set(channel, handler);
+  };
   return {
+    reconnectableChannels,
     handle(channel: string, handler: IpcHandler) {
-      assert.equal(
-        handlers.has(channel),
-        false,
-        `duplicate handler: ${channel}`,
-      );
-      handlers.set(channel, handler);
+      register(channel, handler);
+    },
+    handleReconnectableRead(channel: string, handler: IpcHandler) {
+      reconnectableChannels.add(channel);
+      register(channel, handler);
     },
     async invoke(channel: string, ...args: unknown[]): Promise<unknown> {
       const handler = handlers.get(channel);
@@ -1125,22 +1458,21 @@ function ipcHarness() {
 }
 
 function registerExecutionIpc(
-  deps: Omit<
-    RuntimeHostSessionExecutionIpcDeps,
-    'sessionCopyCleanup' | 'onBackgroundError' | 'observations'
-  > &
-    Partial<
-      Pick<
-        RuntimeHostSessionExecutionIpcDeps,
-        'sessionCopyCleanup' | 'onBackgroundError' | 'observations'
-      >
-    >,
-  ipcMain: Pick<IpcMain, 'handle'>,
+  deps: Pick<RuntimeHostSessionExecutionIpcDeps, 'client'> &
+    Partial<Omit<RuntimeHostSessionExecutionIpcDeps, 'client'>>,
+  ipcMain: Pick<IpcMain, 'handle'> & { handleReconnectableRead?: IpcMain['handle'] },
 ): (sessionId: string) => Promise<void> {
+  const observer = deps.observer ?? unusedObserver();
   return registerRuntimeHostSessionExecutionIpc(
     {
+      observer,
+      attachmentApprovals: createAttachmentApprovalRegistry(),
+      emitSessionsChanged() {},
+      stat: async () => ({ size: 0 }),
+      resizeImage: async (bytes) => bytes,
+      beforeStop() {},
       ...deps,
-      observations: deps.observations ?? deps.observer,
+      observations: deps.observations ?? observer,
       sessionCopyCleanup: deps.sessionCopyCleanup ?? unusedSessionCopyCleanup(),
       onBackgroundError: deps.onBackgroundError ?? (() => undefined),
     },
@@ -1161,9 +1493,9 @@ function unusedSessionCopyCleanup(): RuntimeHostSessionExecutionIpcDeps['session
   };
 }
 
-function session(cwd = "/workspace"): SessionCatalogProjection {
+function session(cwd = "/workspace", id = 'session-1'): SessionCatalogProjection {
   return {
-    id: "session-1",
+    id,
     revision: 1,
     workspace: {
       target: { kind: 'host_path', path: cwd },
@@ -1187,3 +1519,7 @@ function session(cwd = "/workspace"): SessionCatalogProjection {
     orchestrationMode: "default",
   };
 }
+
+function sideConversationSession(id = 'session-1'): SessionCatalogProjection {
+  return { ...session('/workspace', id), labels: [SIDE_CONVERSATION_SESSION_LABEL] };
+}
diff --git a/apps/desktop/src/main/__tests__/runtime-host-session-observer.test.ts b/apps/desktop/src/main/__tests__/runtime-host-session-observer.test.ts
index 29e4ebcde1..e8c21a387a 100644
--- a/apps/desktop/src/main/__tests__/runtime-host-session-observer.test.ts
+++ b/apps/desktop/src/main/__tests__/runtime-host-session-observer.test.ts
@@ -2570,6 +2570,7 @@ function continuitySnapshot(
       followup: [],
     },
     interactions: { pending: [] },
+    rootTurnSourceMessageIds: [],
     ...overrides,
   };
 }
diff --git a/apps/desktop/src/main/__tests__/seed-completion.test.ts b/apps/desktop/src/main/__tests__/seed-completion.test.ts
deleted file mode 100644
index 37482395a8..0000000000
--- a/apps/desktop/src/main/__tests__/seed-completion.test.ts
+++ /dev/null
@@ -1,40 +0,0 @@
-/*
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied.  See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-
-import assert from 'node:assert/strict';
-import { test } from 'node:test';
-import { notifyWhenSeeded } from '../../preload/seed-completion.js';
-
-test('does not notify after the subscription is disposed', async () => {
-  let resolveSeed!: () => void;
-  const seed = new Promise<void>((resolve) => {
-    resolveSeed = resolve;
-  });
-  let notifications = 0;
-
-  const dispose = notifyWhenSeeded(seed, () => {
-    notifications++;
-  });
-  dispose();
-  resolveSeed();
-  await seed;
-  await Promise.resolve();
-
-  assert.equal(notifications, 0);
-});
diff --git a/apps/desktop/src/main/permission-response-guard.ts b/apps/desktop/src/main/permission-response-guard.ts
index 1dd307674a..4c39f944b5 100644
--- a/apps/desktop/src/main/permission-response-guard.ts
+++ b/apps/desktop/src/main/permission-response-guard.ts
@@ -65,6 +65,7 @@ interface NormalizedSendSessionCommand {
 type NormalizedStopSessionInput = {
   source?: 'stop_button';
   expectedTurnId?: string;
+  expectedAdmissionId?: string;
 };
 
 export function normalizeSandboxBoundaryResponse(input: unknown): SandboxBoundaryResponse {
@@ -324,9 +325,17 @@ export function normalizeStopSessionInput(input: unknown): NormalizedStopSession
         'Invalid stop session expectedTurnId',
         MAX_TURN_ID_LENGTH,
       );
+  const expectedAdmissionId = value.expectedAdmissionId === undefined
+    ? undefined
+    : normalizeRequiredString(
+        value.expectedAdmissionId,
+        'Invalid stop session expectedAdmissionId',
+        MAX_TURN_ID_LENGTH,
+      );
   return {
     ...(value.source ? { source: 'stop_button' as const } : {}),
     ...(expectedTurnId ? { expectedTurnId } : {}),
+    ...(expectedAdmissionId ? { expectedAdmissionId } : {}),
   };
 }
 
diff --git a/apps/desktop/src/main/runtime-host-session-execution-ipc-main.ts b/apps/desktop/src/main/runtime-host-session-execution-ipc-main.ts
index bd961f7fdd..533c8786ec 100644
--- a/apps/desktop/src/main/runtime-host-session-execution-ipc-main.ts
+++ b/apps/desktop/src/main/runtime-host-session-execution-ipc-main.ts
@@ -20,8 +20,12 @@
 import { randomUUID } from "node:crypto";
 import type { IpcMainInvokeEvent } from "electron";
 import { MAX_ATTACHMENT_COUNT } from '@maka/core/attachments';
-import { RuntimeHostOperationError } from '@maka/runtime-host/client';
+import {
+  RuntimeHostOperationError,
+  RuntimeHostRequestInterruptedError,
+} from '@maka/runtime-host/client';
 import { SKILL_INVOCATION_TOKEN_SOURCE } from '@maka/core/skill-invocation-token';
+import { isSideConversationSession } from '@maka/core/side-conversation';
 import {
   type SessionChangedEvent,
   type SessionChangedReason,
@@ -56,6 +60,7 @@ import {
   type RuntimeHostTranscriptTarget,
 } from "./runtime-host-session-observer.js";
 import type { DesktopTranscriptRangeRequest } from '../preload/transcript-contract.js';
+import type { DesktopSessionStopResult } from '../preload/bridge-contract.js';
 import { toDesktopHostSessionSummary } from "./runtime-host-session-catalog-ipc-main.js";
 import { mergeWorkspaceFileInlineReferences } from "./session-workspace-inline-references.js";
 
@@ -63,6 +68,24 @@ type SideConversationBranchResult =
   | { readonly ok: true; readonly session: ReturnType<typeof toDesktopHostSessionSummary> }
   | { readonly ok: false; readonly reason: 'session_busy' | 'operation_unavailable' };
 
+async function retryDispatchedCommand<T>(
+  command: () => Promise<T>,
+  waitForReconnect: () => Promise<unknown>,
+): Promise<T> {
+  try {
+    return await command();
+  } catch (error) {
+    if (
+      !(error instanceof RuntimeHostRequestInterruptedError) ||
+      error.dispatch !== 'dispatched'
+    ) {
+      throw error;
+    }
+    await waitForReconnect();
+    return command();
+  }
+}
+
 type RuntimeHostSessionExecutionClient = Pick<
   DesktopRuntimeHostClient,
   | "answerInteraction"
@@ -88,6 +111,23 @@ type RuntimeHostSessionExecutionClient = Pick<
   | "updateSessionConfiguration"
 >;
 
+async function submitMessageWithReconnect(
+  client: Pick<RuntimeHostSessionExecutionClient, 'getSession' | 'submitMessage'>,
+  input: Parameters<RuntimeHostSessionExecutionClient['submitMessage']>[0],
+): Promise<Awaited<ReturnType<RuntimeHostSessionExecutionClient['submitMessage']>> | undefined> {
+  try {
+    return await retryDispatchedCommand(
+      () => client.submitMessage(input),
+      () => client.getSession(input.sessionId),
+    );
+  } catch (error) {
+    if (error instanceof RuntimeHostOperationError && error.code === 'outcome_unknown') {
+      return undefined;
+    }
+    throw error;
+  }
+}
+
 export interface RuntimeHostSessionExecutionIpcDeps {
   client: RuntimeHostSessionExecutionClient;
   observer: RuntimeHostSessionObserver;
@@ -150,15 +190,21 @@ export function registerRuntimeHostSessionExecutionIpc(
   const newId = deps.newId ?? randomUUID;
   const stopSession = createRuntimeHostSessionStop(deps, newId);
 
-  ipcMain.handle(
+  handleReconnectableRead(
+    ipcMain,
     "sessions:observe",
     async (event, sessionId: unknown, observerId: unknown) => {
       const normalizedSessionId = requiredId(sessionId, "Session");
       const normalizedObserverId = requiredId(observerId, "Session observer");
+      const session = await deps.client.getSession(normalizedSessionId);
+      if (!session) {
+        throw new Error(`Runtime Host Session not found: ${normalizedSessionId}`);
+      }
       await deps.observations.observe(
         normalizedSessionId,
         normalizedObserverId,
         event.sender as RuntimeHostSessionObserverTarget,
+        isSideConversationSession(session.labels),
       );
     },
   );
@@ -216,6 +262,7 @@ export function registerRuntimeHostSessionExecutionIpc(
       const session = await deps.client.getSession(sessionId);
       if (!session)
         throw new Error(`Runtime Host Session not found: ${sessionId}`);
+      const sideConversation = isSideConversationSession(session.labels);
       const turnId = command.turnId ?? newId();
       let attachments = retainedAttachmentsForSession(
         sessionId,
@@ -276,7 +323,12 @@ export function registerRuntimeHostSessionExecutionIpc(
       };
       let startResult;
       try {
-        startResult = await deps.client.startTurn(startInput);
+        startResult = sideConversation
+          ? await retryDispatchedCommand(
+              () => deps.client.startTurn(startInput),
+              () => deps.client.getSession(sessionId),
+            )
+          : await deps.client.startTurn(startInput);
       } catch (error) {
         // The renderer routes text at a session it sees as running to
         // `sessions:steer`, but its view can lag the Host: another window, a
@@ -297,15 +349,27 @@ export function registerRuntimeHostSessionExecutionIpc(
         ) {
           throw error;
         }
-        const submitted = await deps.client.submitMessage({
+        // Preserve the renderer's command identity in the durable message so
+        // a lost IPC reply can be reconciled as root-vs-steering later.
+        const messageId = turnId;
+        const emptySkillInvocation = { loaded: [], failed: [], receipts: [] };
+        const submitInput = {
           sessionId,
-          // Preserve the renderer's command identity in the durable message so
-          // a lost IPC reply can be reconciled as root-vs-steering later.
-          messageId: turnId,
+          messageId,
           content: startInput.content,
-          placement: "current_turn",
-        });
-        const emptySkillInvocation = { loaded: [], failed: [], receipts: [] };
+          placement: 'current_turn' as const,
+        };
+        const submitted = sideConversation
+          ? await submitMessageWithReconnect(deps.client, submitInput)
+          : await deps.client.submitMessage(submitInput);
+        if (!submitted) {
+          return {
+            ok: false as const,
+            reason: 'outcome_unknown' as const,
+            messageId,
+            skillInvocation: emptySkillInvocation,
+          };
+        }
         if (submitted.disposition === "turn_started") {
           deps.emitSessionsChanged("status-change", sessionId, {
             turnId: submitted.turnId,
@@ -325,6 +389,7 @@ export function registerRuntimeHostSessionExecutionIpc(
           ok: true as const,
           steered: true as const,
           turnId,
+          ...(sideConversation ? { messageId } : {}),
           attachments,
           inlineReferences,
           skillInvocation: emptySkillInvocation,
@@ -351,15 +416,22 @@ export function registerRuntimeHostSessionExecutionIpc(
 
   ipcMain.handle(
     "sessions:steer",
-    async (_event, sessionId: string, text: unknown) => {
+    async (_event, sessionId: string, text: unknown, admissionId: unknown) => {
       const content = steeringContent(text);
-      await deps.client.submitMessage({
+      const messageId = admissionId === undefined ? newId() : requiredId(admissionId, "Admission");
+      const submitted = await submitMessageWithReconnect(deps.client, {
         sessionId,
-        messageId: newId(),
+        messageId,
         content: { text: content },
         placement: "current_turn",
       });
-      return { kind: "queued" as const };
+      if (!submitted) return { kind: 'outcome_unknown' as const, messageId };
+      return submitted.disposition === "turn_started"
+        ? { kind: "started" as const, turnId: submitted.turnId }
+        : {
+            kind: "queued" as const,
+            messageId,
+          };
     },
   );
   ipcMain.handle(
@@ -512,7 +584,7 @@ export function registerRuntimeHostSessionExecutionIpc(
     "sessions:stop",
     async (_event, sessionId: string, input: unknown) => {
       const normalized = normalizeStopSessionInput(input);
-      return stopSession(sessionId, normalized.expectedTurnId);
+      return stopSession(sessionId, normalized);
     },
   );
 
@@ -685,7 +757,9 @@ export function registerRuntimeHostSessionExecutionIpc(
       return toDesktopHostSessionSummary(revision);
     },
   );
-  return stopSession;
+  return async (sessionId) => {
+    await stopSession(sessionId);
+  };
 }
 
 function normalizeTranscriptRangeRequest(input: unknown): DesktopTranscriptRangeRequest {
@@ -736,8 +810,39 @@ function createRuntimeHostSessionStop(
     "beforeStop" | "client" | "observer" | "emitSessionsChanged"
   >,
   newId: () => string = randomUUID,
-): (sessionId: string, expectedTurnId?: string) => Promise<void> {
-  return async (sessionId, expectedTurnId) => {
+): (
+  sessionId: string,
+  target?: { readonly expectedTurnId?: string; readonly expectedAdmissionId?: string },
+) => Promise<DesktopSessionStopResult> {
+  return async (sessionId, target = {}) => {
+    let expectedTurnId = target.expectedTurnId;
+    if (target.expectedAdmissionId) {
+      const observed = await deps.observer.snapshot(sessionId);
+      const root = observed.rootTurn;
+      const entry = [...observed.queue.steering, ...observed.queue.followup].find(
+        (candidate) => candidate.messageId === target.expectedAdmissionId,
+      );
+      if (entry?.state === 'queued') {
+        await deps.client.retractQueueEntry({
+          sessionId,
+          entryId: entry.entryId,
+          retractId: newId(),
+        });
+        deps.emitSessionsChanged('status-change', sessionId);
+        return { kind: 'retracted', messageId: entry.messageId };
+      }
+      if (
+        root &&
+        !isTerminalStatus(root.status) &&
+        (root.turnId === target.expectedAdmissionId ||
+          observed.rootTurnSourceMessageIds.includes(target.expectedAdmissionId) ||
+          entry?.state === 'in_flight')
+      ) {
+        expectedTurnId = root.turnId;
+      } else {
+        throw new Error('Host admission outcome is unknown');
+      }
+    }
     if (expectedTurnId) {
       const observed = (await deps.observer.snapshot(sessionId)).rootTurn;
       if (
diff --git a/apps/desktop/src/main/runtime-host-session-observation-registry.ts b/apps/desktop/src/main/runtime-host-session-observation-registry.ts
index e60ca88983..0e95057c59 100644
--- a/apps/desktop/src/main/runtime-host-session-observation-registry.ts
+++ b/apps/desktop/src/main/runtime-host-session-observation-registry.ts
@@ -76,6 +76,7 @@ function requireTranscriptSource(
 
 interface SessionObservationRegistration {
   readonly sessionId: string;
+  readonly messageAdmissions: boolean;
   readonly target: RuntimeHostSessionObserverTarget;
   readonly destroyedListener: () => void;
   readonly ready: ObservationReadiness;
@@ -151,6 +152,7 @@ export class RuntimeHostSessionObservationRegistry {
             registration.sessionId,
             observerId,
             bindTarget(registration.target),
+            registration.messageAdmissions,
           );
           if (
             this.#source !== source ||
@@ -218,11 +220,16 @@ export class RuntimeHostSessionObservationRegistry {
     sessionId: string,
     observerId: string,
     target: RuntimeHostSessionObserverTarget,
+    messageAdmissions = false,
   ): Promise<void> {
     this.#assertOpen();
     const previous = this.#registrations.get(observerId);
     if (previous) {
-      if (previous.sessionId !== sessionId || previous.target.id !== target.id) {
+      if (
+        previous.sessionId !== sessionId ||
+        previous.target.id !== target.id ||
+        previous.messageAdmissions !== messageAdmissions
+      ) {
         throw new Error("Runtime Host Session observer identity was reused");
       }
       return previous.ready.promise;
@@ -235,6 +242,7 @@ export class RuntimeHostSessionObservationRegistry {
     void ready.promise.catch(() => undefined);
     const registration: SessionObservationRegistration = {
       sessionId,
+      messageAdmissions,
       target,
       destroyedListener,
       ready,
@@ -246,7 +254,12 @@ export class RuntimeHostSessionObservationRegistry {
     const source = this.#source;
     if (!source) return registration.ready.promise;
     try {
-      await source.observe(sessionId, observerId, this.#bindTarget(target));
+      await source.observe(
+        sessionId,
+        observerId,
+        this.#bindTarget(target),
+        messageAdmissions,
+      );
       if (
         this.#source === source &&
         this.#registrations.get(observerId) === registration
diff --git a/apps/desktop/src/main/runtime-host-session-observer.ts b/apps/desktop/src/main/runtime-host-session-observer.ts
index 390ee5f34e..273dfca234 100644
--- a/apps/desktop/src/main/runtime-host-session-observer.ts
+++ b/apps/desktop/src/main/runtime-host-session-observer.ts
@@ -118,6 +118,7 @@ interface ObservedSessionState {
   snapshot?: SessionContinuitySnapshot;
   projector?: RuntimeHostSessionProjector;
   transcriptAccess: number;
+  messageAdmissions: boolean;
   closing: boolean;
 }
 
@@ -425,6 +426,7 @@ export class RuntimeHostSessionObserver {
     sessionId: string,
     observerId: string,
     target: RuntimeHostSessionObserverTarget,
+    messageAdmissions = false,
   ): Promise<void> {
     this.#assertOpen();
     const previous = this.#observers.get(observerId);
@@ -438,6 +440,10 @@ export class RuntimeHostSessionObserver {
       return;
     }
     const state = this.#state(sessionId);
+    if (messageAdmissions && !state.messageAdmissions) {
+      state.messageAdmissions = true;
+      state.projector?.enableMessageAdmissions();
+    }
     let group = state.targets.get(target.id);
     if (!group) {
       const destroyedListener = () => {
@@ -622,6 +628,7 @@ export class RuntimeHostSessionObserver {
       subscriptionOwner,
       pendingTranscriptConsumers: 0,
       transcriptAccess: 0,
+      messageAdmissions: false,
       closing: false,
     };
     this.#states.set(sessionId, state);
@@ -800,6 +807,7 @@ export class RuntimeHostSessionObserver {
       subscription.replica.projectionSeed,
       this.#now,
       subscription.activeAssistantStreams,
+      state.messageAdmissions,
     );
     const terminalTurnIds = new Set<string>();
     for (const turnId of state.watchedTurnIds) {
diff --git a/apps/desktop/src/preload/bridge-contract.d.ts b/apps/desktop/src/preload/bridge-contract.d.ts
index d478543721..293268ad20 100644
--- a/apps/desktop/src/preload/bridge-contract.d.ts
+++ b/apps/desktop/src/preload/bridge-contract.d.ts
@@ -48,7 +48,6 @@ import type {
   SessionCommand,
   SessionEvent,
   ShellRunUpdate,
-  QueueEnqueueOutcome,
 } from '@maka/core/events';
 import type { UserQuestionResponse } from '@maka/core/user-question';
 import type { PermissionMode } from '@maka/core/permission';
@@ -207,6 +206,10 @@ export type DesktopSideConversationBranchResult =
   | { ok: true; session: DesktopSessionSummary }
   | { ok: false; reason: 'session_busy' | 'operation_unavailable' };
 
+export type DesktopSessionStopResult =
+  | { kind: 'retracted'; messageId: string }
+  | undefined;
+
 export type DesktopReviseBeforeTurnInput = ReviseBeforeTurnInput & {
   /** Stable target identity for retrying one Desktop copy action. */
   copyId: string;
@@ -721,7 +724,7 @@ export interface MakaBridge {
       sessionId: string,
       command:
         | SessionCommand
-        | {
+          | {
             type: 'send';
             turnId: string;
             text: string;
@@ -743,7 +746,18 @@ export interface MakaBridge {
            * The send raced a root Turn another client opened first and was
            * queued into it as steering instead of starting `turnId`.
            */
-          steered?: true;
+          steered?: never;
+          messageId?: never;
+          attachments: import('@maka/core/events').AttachmentRef[];
+          inlineReferences: import('@maka/core/events').InlineReference[];
+          skillInvocation: import('@maka/runtime/skill-invocation').SkillInvocationResult;
+        }
+      | {
+          ok: true;
+          turnId: string;
+          steered: true;
+          /** Host admission identity for the message queued as steering. */
+          messageId: string;
           attachments: import('@maka/core/events').AttachmentRef[];
           inlineReferences: import('@maka/core/events').InlineReference[];
           skillInvocation: import('@maka/runtime/skill-invocation').SkillInvocationResult;
@@ -753,12 +767,30 @@ export interface MakaBridge {
           reason: 'skill_invocation_failed';
           skillInvocation: import('@maka/runtime/skill-invocation').SkillInvocationResult;
         }
+      | {
+          ok: false;
+          reason: 'outcome_unknown';
+          messageId: string;
+          skillInvocation: import('@maka/runtime/skill-invocation').SkillInvocationResult;
+        }
     >;
     stop(
       sessionId: string,
-      input?: { source?: 'stop_button'; expectedTurnId?: string },
-    ): Promise<void>;
-    steer(sessionId: string, text: string): Promise<QueueEnqueueOutcome>;
+      input?: {
+        source?: 'stop_button';
+        expectedTurnId?: string;
+        expectedAdmissionId?: string;
+      },
+    ): Promise<DesktopSessionStopResult>;
+    steer(
+      sessionId: string,
+      text: string,
+      admissionId?: string,
+    ): Promise<
+      | { kind: 'queued'; messageId: string }
+      | { kind: 'outcome_unknown'; messageId: string }
+      | { kind: 'started'; turnId: string }
+    >;
     enqueue(
       sessionId: string,
       placement: 'current_turn' | 'next_turn',
@@ -825,6 +857,7 @@ export interface MakaBridge {
       handler: (event: SessionEvent) => void,
       onSeeded?: () => void,
       onObservationSeed?: (phase: 'pending' | 'ready') => void,
+      onSeedError?: (error: unknown) => void,
     ): () => void;
     subscribeChanges(handler: (event: SessionChangedEvent) => void): () => void;
     archive(sessionId: string, options?: { revisionFamily?: boolean }): Promise<void>;
diff --git a/apps/desktop/src/preload/preload.ts b/apps/desktop/src/preload/preload.ts
index 656472bf20..661baf0b69 100644
--- a/apps/desktop/src/preload/preload.ts
+++ b/apps/desktop/src/preload/preload.ts
@@ -20,7 +20,6 @@
 import { contextBridge, ipcRenderer } from 'electron';
 import { encodeIngestItems } from './attachment-ingest-payload.js';
 import { collectThreadSearchResponses } from './multi-host-thread-search.js';
-import { notifyWhenSeeded } from './seed-completion.js';
 import { releaseSessionObservation } from './session-observation-release.js';
 import type {
   MakaBridge,
@@ -31,6 +30,7 @@ import type {
   RendererIngestInput,
   DesktopBranchFromTurnInput,
   DesktopSideConversationBranchResult,
+  DesktopSessionStopResult,
   DesktopReviseBeforeTurnInput,
   AppUpdateInstallRequest,
   AppUpdateInstallResult,
@@ -116,7 +116,6 @@ import type {
   SessionCommand,
   SessionEvent,
   ShellRunUpdate,
-  QueueEnqueueOutcome,
 } from '@maka/core/events';
 import type { UserQuestionResponse } from '@maka/core/user-question';
 import type { PermissionMode } from '@maka/core/permission';
@@ -1528,7 +1527,7 @@ const makaBridge = {
       sessionId: string,
       command:
         | SessionCommand
-        | {
+          | {
             type: 'send';
             turnId: string;
             text: string;
@@ -1553,6 +1552,12 @@ const makaBridge = {
           reason: 'skill_invocation_failed';
           skillInvocation: import('@maka/runtime/skill-invocation').SkillInvocationResult;
         }
+      | {
+          ok: false;
+          reason: 'outcome_unknown';
+          messageId: string;
+          skillInvocation: import('@maka/runtime/skill-invocation').SkillInvocationResult;
+        }
     > {
       const session = await runtimeHostSessionRef(sessionId);
       const send = async (input: SessionCommand | Record<string, unknown>) => {
@@ -1589,12 +1594,24 @@ const makaBridge = {
     },
     stop(
       sessionId: string,
-      input?: { source?: 'stop_button'; expectedTurnId?: string },
-    ): Promise<void> {
+      input?: {
+        source?: 'stop_button';
+        expectedTurnId?: string;
+        expectedAdmissionId?: string;
+      },
+    ): Promise<DesktopSessionStopResult> {
       return invokeSessionRuntimeHost('sessions:stop', sessionId, input);
     },
-    steer(sessionId: string, text: string): Promise<QueueEnqueueOutcome> {
-      return invokeSessionRuntimeHost('sessions:steer', sessionId, text);
+    steer(
+      sessionId: string,
+      text: string,
+      admissionId?: string,
+    ): Promise<
+      | { kind: 'queued'; messageId: string }
+      | { kind: 'outcome_unknown'; messageId: string }
+      | { kind: 'started'; turnId: string }
+    > {
+      return invokeSessionRuntimeHost('sessions:steer', sessionId, text, admissionId);
     },
     async enqueue(
       sessionId: string,
@@ -1729,6 +1746,7 @@ const makaBridge = {
       handler: (event: SessionEvent) => void,
       onSeeded?: () => void,
       onObservationSeed?: (phase: 'pending' | 'ready') => void,
+      onSeedError?: (error: unknown) => void,
     ): () => void {
       const observerId = crypto.randomUUID();
       let disposed = false;
@@ -1736,15 +1754,23 @@ const makaBridge = {
       let unsubscribeObservationSeed = () => {};
       const observeDispatch = runtimeHostSessionRef(sessionId).then((session) => {
         if (disposed) return { completion: Promise.resolve() };
-        unsubscribeEvents = subscribeRuntimeHostEvent(
+        const profileId = runtimeHostMetadata.get(session.scope.hostId)?.profileId;
+        if (!profileId) throw new Error('The Runtime Host profile for this task is unavailable');
+        // Keep the renderer listener across Host target epochs. The observer
+        // registry restores this observer on the replacement target. Profile
+        // identity admits that replacement without accepting another Host's
+        // same-named Session channel.
+        unsubscribeEvents = subscribeEveryRuntimeHostEvent(
           `sessions:event:${session.sessionId}`,
-          session.scope,
-          (event: SessionEvent) => handler(projectDesktopSessionEvent(session.scope, event)),
+          (scope, event: SessionEvent) => {
+            if (runtimeHostMetadata.get(scope.hostId)?.profileId !== profileId) return;
+            handler(projectDesktopSessionEvent(scope, event));
+          },
         );
-        unsubscribeObservationSeed = subscribeRuntimeHostEvent(
+        unsubscribeObservationSeed = subscribeEveryRuntimeHostEvent(
           'sessions:observation-seed',
-          session.scope,
-          (payload: { sessionId?: string; phase?: string }) => {
+          (scope, payload: { sessionId?: string; phase?: string }) => {
+            if (runtimeHostMetadata.get(scope.hostId)?.profileId !== profileId) return;
             if (payload.sessionId !== session.sessionId) return;
             if (payload.phase === 'pending' || payload.phase === 'ready') {
               onObservationSeed?.(payload.phase);
@@ -1761,10 +1787,16 @@ const makaBridge = {
         };
       });
       const observing = observeDispatch.then(({ completion }) => completion);
-      const disposeSeedNotification = notifyWhenSeeded(observing, onSeeded);
+      void observing.then(
+        () => {
+          if (!disposed) onSeeded?.();
+        },
+        (error: unknown) => {
+          if (!disposed) onSeedError?.(error);
+        },
+      );
       return () => {
         disposed = true;
-        disposeSeedNotification();
         unsubscribeObservationSeed();
         unsubscribeEvents();
         void releaseSessionObservation(observeDispatch, () =>
diff --git a/apps/desktop/src/preload/seed-completion.ts b/apps/desktop/src/preload/seed-completion.ts
deleted file mode 100644
index 464abe4b7b..0000000000
--- a/apps/desktop/src/preload/seed-completion.ts
+++ /dev/null
@@ -1,34 +0,0 @@
-/*
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied.  See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-
-export function notifyWhenSeeded(
-  seed: Promise<unknown>,
-  notify: (() => void) | undefined,
-): () => void {
-  let disposed = false;
-  void seed
-    .then(() => {
-      if (!disposed) notify?.();
-    })
-    .catch(() => undefined);
-
-  return () => {
-    disposed = true;
-  };
-}
diff --git a/apps/desktop/src/renderer/features/workbar/ports.ts b/apps/desktop/src/renderer/features/workbar/ports.ts
index fb14676742..37e97ff710 100644
--- a/apps/desktop/src/renderer/features/workbar/ports.ts
+++ b/apps/desktop/src/renderer/features/workbar/ports.ts
@@ -18,7 +18,6 @@
  */
 
 import type {
-  QueueEnqueueOutcome,
   QuoteRef,
   SessionEvent,
   ShellRunUpdate,
@@ -197,8 +196,15 @@ export interface WorkbarAttachmentsService {
 }
 
 export type SideChatSendResult =
-  | { ok: true }
-  | { ok: false; reason?: string };
+  | { ok: true; turnId: string; steered?: false }
+  | { ok: true; turnId: string; steered: true; messageId: string }
+  | { ok: false; reason: 'outcome_unknown'; messageId: string }
+  | { ok: false; reason?: string; messageId?: never };
+
+export type SideChatSteerResult =
+  | { kind: 'queued'; messageId: string }
+  | { kind: 'outcome_unknown'; messageId: string }
+  | { kind: 'started'; turnId: string };
 
 export interface SideChatSessionPort {
   listSessions(): Promise<SessionSummary[]>;
@@ -231,8 +237,11 @@ export interface SideChatSessionPort {
       attachmentItems?: WorkbarIngestInput[];
     },
   ): Promise<SideChatSendResult>;
-  stop(sessionId: string): Promise<void>;
-  steer(sessionId: string, text: string): Promise<QueueEnqueueOutcome>;
+  stop(
+    sessionId: string,
+    admissionId?: string,
+  ): Promise<{ kind: 'retracted'; messageId: string } | undefined>;
+  steer(sessionId: string, text: string, admissionId?: string): Promise<SideChatSteerResult>;
   setPermissionMode(
     sessionId: string,
     mode: PermissionMode,
@@ -249,6 +258,8 @@ export interface SideChatSessionPort {
   subscribeEvents(
     sessionId: string,
     handler: (event: SessionEvent) => void,
+    onSeeded?: () => void,
+    onSeedError?: (error: unknown) => void,
   ): WorkbarUnsubscribe;
   subscribeSessionChanges(handler: (event: SessionChangedEvent) => void): WorkbarUnsubscribe;
 }
diff --git a/apps/desktop/src/renderer/features/workbar/testing.ts b/apps/desktop/src/renderer/features/workbar/testing.ts
index f2e3e940b5..da788175e0 100644
--- a/apps/desktop/src/renderer/features/workbar/testing.ts
+++ b/apps/desktop/src/renderer/features/workbar/testing.ts
@@ -136,7 +136,10 @@ export function createFakeWorkbarServices(
       regenerateTurn: async () => undefined,
       respondToSandboxBoundary: async () => undefined,
       respondToUserQuestion: async () => undefined,
-      subscribeEvents: noopSubscription,
+      subscribeEvents: (_sessionId, _handler, onSeeded) => {
+        onSeeded?.();
+        return noopSubscription();
+      },
       subscribeSessionChanges: noopSubscription,
     },
     ...overrides,
diff --git a/apps/desktop/src/renderer/features/workbar/tools/side-chat/quote-companion-core.ts b/apps/desktop/src/renderer/features/workbar/tools/side-chat/quote-companion-core.ts
index dceb846301..626f6d6dce 100644
--- a/apps/desktop/src/renderer/features/workbar/tools/side-chat/quote-companion-core.ts
+++ b/apps/desktop/src/renderer/features/workbar/tools/side-chat/quote-companion-core.ts
@@ -31,6 +31,7 @@ import type { SessionSummary, TurnRecord } from '@maka/core/session';
 import type { UiLocale } from '@maka/core/ui-locale';
 import type {
   SideChatSessionPort,
+  SideChatSendResult,
   WorkbarIngestInput,
 } from '../../ports.js';
 import {
@@ -167,19 +168,22 @@ export async function dismissCompanionCopy(
 }
 
 /**
- * The shared Composer's `streaming` input means "a turn is interruptible", not
- * merely "a text delta has arrived". Keep the companion interruptible from the
- * optimistic waiting projection through live output; `processing` only chooses
- * the quieter pre-first-token presentation inside that same in-flight window.
+ * The shared Composer's `streaming` input means Host work is interruptible, not
+ * merely that a text delta has arrived. A pending admission remains stoppable
+ * before it owns a Turn; an admitted Turn remains stoppable through live output.
  */
 export function deriveCompanionComposerState(
-  turnInFlight: boolean,
+  hasPendingAdmission: boolean,
+  activeTurnId: string | null,
   liveTurn: LiveTurnProjection | undefined,
 ): { streaming: boolean; processing: boolean } {
-  const streaming = turnInFlight && liveTurn?.terminal !== true;
+  const activeTurnStreaming = activeTurnId !== null && liveTurn?.terminal !== true;
+  const streaming = hasPendingAdmission || activeTurnStreaming;
   return {
     streaming,
-    processing: streaming && (!liveTurn || liveTurn.phase === 'waiting'),
+    processing:
+      streaming &&
+      (!activeTurnStreaming || !liveTurn || liveTurn.phase === 'waiting'),
   };
 }
 
@@ -283,7 +287,9 @@ export async function ensureCompanionFork(
 }
 
 export type CompanionTurnResult =
-  | { status: 'sent'; forkId: string }
+  | { status: 'sent'; forkId: string; turnId: string; steered?: false }
+  | { status: 'sent'; forkId: string; turnId: string; steered: true; messageId: string }
+  | { status: 'pending'; forkId: string; messageId: string }
   | { status: 'disposed' }
   | { status: 'error'; code: CompanionErrorCode };
 
@@ -335,7 +341,7 @@ export async function performCompanionTurn(
     if (createdForkId) scheduleCompanionCleanup(deps, createdForkId);
     return { status: 'disposed' };
   }
-  let result: { ok: true } | { ok: false; reason?: string };
+  let result: SideChatSendResult;
   try {
     result = await deps.api.send(forkId, {
       type: 'send',
@@ -353,10 +359,15 @@ export async function performCompanionTurn(
   // run was started, so surface the error and keep the quotes for retry rather
   // than reporting success and hanging in the processing state.
   if (!result.ok) {
+    if (result.reason === 'outcome_unknown' && result.messageId) {
+      return { status: 'pending', forkId, messageId: result.messageId };
+    }
     return { status: 'error', code: 'send_rejected' };
   }
   deps.onQuotesConsumed();
-  return { status: 'sent', forkId };
+  return result.steered
+    ? { status: 'sent', forkId, turnId: result.turnId, steered: true, messageId: result.messageId }
+    : { status: 'sent', forkId, turnId: result.turnId };
 }
 
 export function isCompanionTurnTerminal(event: SessionEvent): boolean {
diff --git a/apps/desktop/src/renderer/features/workbar/tools/side-chat/use-quote-companion.ts b/apps/desktop/src/renderer/features/workbar/tools/side-chat/use-quote-companion.ts
index 7c4bcb5be8..cc5c5fec10 100644
--- a/apps/desktop/src/renderer/features/workbar/tools/side-chat/use-quote-companion.ts
+++ b/apps/desktop/src/renderer/features/workbar/tools/side-chat/use-quote-companion.ts
@@ -61,6 +61,37 @@ import {
 } from './quote-companion-panel-state.js';
 import type { CompanionForkVisibilityEvent } from './quote-companion-visibility.js';
 
+type PendingAdmission = {
+  messageId: string;
+  events: SessionEvent[];
+  consumeOnAdmission?: () => void;
+  stopPromise?: Promise<'confirmed' | 'unknown'>;
+};
+
+type AdmissionOutcome =
+  | { kind: 'admitted'; turnId: string }
+  | { kind: 'retracted' };
+
+function admissionOutcomeForMessage(
+  events: readonly SessionEvent[],
+  messageId: string,
+): AdmissionOutcome | undefined {
+  const admitted = events.find(
+    (event) =>
+      event.type === 'message_admission' &&
+      event.outcome === 'admitted' &&
+      event.messageId === messageId,
+  );
+  if (admitted) return { kind: 'admitted', turnId: admitted.turnId };
+  const retracted = events.some(
+    (event) =>
+      event.type === 'message_admission' &&
+      event.outcome === 'retracted' &&
+      event.messageId === messageId,
+  );
+  return retracted ? { kind: 'retracted' } : undefined;
+}
+
 export interface UseQuoteCompanionInput {
   /** Stable owner for the currently mounted panel generation. */
   panelId: string;
@@ -157,9 +188,11 @@ export function useQuoteCompanion(input: UseQuoteCompanionInput): UseQuoteCompan
   const sourceSessionIdRef = useRef(sourceSession?.id);
   sourceSessionIdRef.current = sourceSessionId;
   const forkSetupPromiseRef = useRef<Promise<EnsureCompanionForkResult> | null>(null);
-  const stopRequestedRef = useRef(false);
+  const stopRequestRef = useRef<Promise<unknown> | null>(null);
   const activeTurnIdRef = useRef<string | null>(null);
-  const turnInFlightRef = useRef(false);
+  const pendingAdmissionRef = useRef<PendingAdmission | null>(null);
+  const subscriptionReadyRef = useRef<Promise<void>>(Promise.resolve());
+  const submitLockRef = useRef(false);
   const settlingTurnIdsRef = useRef<Set<string>>(new Set());
   const onForkVisibilityChangeRef = useRef(onForkVisibilityChange);
   onForkVisibilityChangeRef.current = onForkVisibilityChange;
@@ -173,7 +206,13 @@ export function useQuoteCompanion(input: UseQuoteCompanionInput): UseQuoteCompan
   const liveTurnRef = useRef(liveTurn);
   liveTurnRef.current = liveTurn;
   const [interactions, setInteractions] = useState<InteractionQueues>({});
-  const [turnInFlight, setTurnInFlight] = useState(false);
+  const [pendingAdmission, setPendingAdmissionState] = useState<PendingAdmission | null>(null);
+  const { streaming, processing } = deriveCompanionComposerState(
+    pendingAdmission !== null,
+    activeTurnIdRef.current,
+    liveTurn,
+  );
+  const turnInFlight = streaming;
   const [preparing, setPreparing] = useState(Boolean(sourceSession));
   const [permissionModePending, setPermissionModePending] = useState(false);
   const [regeneratePendingTurnId, setRegeneratePendingTurnId] = useState<string | null>(
@@ -192,25 +231,17 @@ export function useQuoteCompanion(input: UseQuoteCompanionInput): UseQuoteCompan
   const mountedRef = useMountedRef();
   const dismissalGuardRef = useRef(createCompanionDismissalGuard());
 
-  // Subscribe to the fork's event stream + load its transcript. Called
-  // synchronously the moment the fork is committed, BEFORE the run starts, so
-  // no boundary request / complete can be missed (the stream has no replay).
-  const subscribeToFork = useCallback((forkId: string) => {
-    void sideChat.readSettledMessages(forkId)
-      .then(({ messages }) => {
-        if (mountedRef.current) {
-          setAllMessages((current) => mergeSettledMessages(current, messages));
-        }
-      })
-      .catch(() => {
-        if (mountedRef.current) setError(copyRef.current.errors.settlementFailed);
-      });
-    unsubscribeRef.current = sideChat.subscribeEvents(forkId, (event: SessionEvent) => {
-      if (!mountedRef.current) return;
+  const setPendingAdmission = useCallback((admission: PendingAdmission | null) => {
+    pendingAdmissionRef.current = admission;
+    setPendingAdmissionState(admission);
+  }, []);
+
+  const applyOwnedEvent = useCallback(
+    (forkId: string, event: SessionEvent) => {
       const effect = companionRunEventEffect(
         event,
         activeTurnIdRef.current,
-        stopRequestedRef.current,
+        stopRequestRef.current !== null,
         localeRef.current,
       );
       if (effect.kind === 'ignore') return;
@@ -237,24 +268,155 @@ export function useQuoteCompanion(input: UseQuoteCompanionInput): UseQuoteCompan
             setAllMessages((current) => mergeSettledMessages(current, next));
             setLiveTurn((prev) => (prev ? reconcileTerminalLiveTurn(prev, next) : prev));
             activeTurnIdRef.current = null;
-            turnInFlightRef.current = false;
-            stopRequestedRef.current = false;
-            setTurnInFlight(false);
+            stopRequestRef.current = null;
           })
           .catch(() => {
             if (!mountedRef.current || activeTurnIdRef.current !== settledTurnId) return;
             activeTurnIdRef.current = null;
-            turnInFlightRef.current = false;
-            stopRequestedRef.current = false;
-            setTurnInFlight(false);
+            stopRequestRef.current = null;
             setError((current) => current ?? copyRef.current.errors.settlementFailed);
           })
           .finally(() => {
             settlingTurnIdsRef.current.delete(settledTurnId);
           });
       }
+    },
+    [mountedRef, sideChat],
+  );
+
+  const bindAdmittedTurn = useCallback(
+    (
+      forkId: string,
+      turnId: string,
+      options: { readonly preserveLiveTurn?: boolean } = {},
+    ) => {
+      const admission = pendingAdmissionRef.current;
+      if (!admission) return;
+      setPendingAdmission(null);
+      activeTurnIdRef.current = turnId;
+      ownTurnIdsRef.current.add(turnId);
+      admission.consumeOnAdmission?.();
+      setError(null);
+      setOwnTurnTick((tick) => tick + 1);
+      if (!(options.preserveLiveTurn && liveTurnRef.current?.turnId === turnId)) {
+        setLiveTurn(armLiveTurn(turnId));
+      }
+      for (const event of admission.events) {
+        if (event.turnId === turnId) applyOwnedEvent(forkId, event);
+      }
+    },
+    [applyOwnedEvent, setPendingAdmission],
+  );
+
+  const releaseAdmission = useCallback(
+    (admission: PendingAdmission, message?: string) => {
+      if (pendingAdmissionRef.current !== admission) return;
+      setPendingAdmission(null);
+      if (stopRequestRef.current === admission.stopPromise) stopRequestRef.current = null;
+      if (!activeTurnIdRef.current) setLiveTurn(undefined);
+      if (message) setError(message);
+    },
+    [setPendingAdmission],
+  );
+
+  const resolveAdmission = useCallback(
+    (
+      forkId: string,
+      admission: PendingAdmission,
+      messageId: string,
+      preserveLiveTurn = false,
+    ): AdmissionOutcome | undefined => {
+      const outcome = admissionOutcomeForMessage(admission.events, messageId);
+      if (outcome?.kind === 'admitted') {
+        bindAdmittedTurn(forkId, outcome.turnId, { preserveLiveTurn });
+      } else if (outcome?.kind === 'retracted') {
+        releaseAdmission(admission);
+      }
+      return outcome;
+    },
+    [bindAdmittedTurn, releaseAdmission],
+  );
+
+  // Subscribe to the fork's event stream + load its transcript. Called
+  // synchronously the moment the fork is committed, BEFORE the run starts, so
+  // no boundary request / complete can be missed (the stream has no replay).
+  const subscribeToFork = useCallback((forkId: string): Promise<void> => {
+    let resolveReady!: () => void;
+    let rejectReady!: (error: unknown) => void;
+    let readySettled = false;
+    const ready = new Promise<void>((resolve, reject) => {
+      resolveReady = () => {
+        if (readySettled) return;
+        readySettled = true;
+        resolve();
+      };
+      rejectReady = (error: unknown) => {
+        if (readySettled) return;
+        readySettled = true;
+        reject(error);
+      };
     });
-  }, [mountedRef, sideChat]);
+    // A subscription can fail before the first send. Keep that failure
+    // observable to a later send without creating an unhandled rejection now.
+    void ready.catch(() => undefined);
+    void sideChat.readSettledMessages(forkId)
+      .then(({ messages }) => {
+        if (mountedRef.current) {
+          setAllMessages((current) => mergeSettledMessages(current, messages));
+        }
+      })
+      .catch(() => {
+        if (mountedRef.current) setError(copyRef.current.errors.settlementFailed);
+      });
+    const unsubscribe = sideChat.subscribeEvents(
+      forkId,
+      (event: SessionEvent) => {
+        if (!mountedRef.current) return;
+        const admission = pendingAdmissionRef.current;
+        if (event.type === 'error' && event.recoverable) {
+          if (admission) {
+            // Observation failure does not prove whether Host admitted the
+            // dispatched command. Keep its identity until Host events or the
+            // command result provide an authoritative outcome.
+            setError(copyRef.current.errors.sendFailed);
+            return;
+          }
+          setError(copyRef.current.errors.sendFailed);
+          const retry = Promise.reject(new Error(event.message));
+          void retry.catch(() => undefined);
+          subscriptionReadyRef.current = retry;
+          return;
+        }
+        if (admission) {
+          if (
+            event.type === 'message_admission' &&
+            event.messageId === admission.messageId
+          ) {
+            admission.events.push(event);
+            resolveAdmission(forkId, admission, admission.messageId, true);
+          } else if (event.turnId === activeTurnIdRef.current) {
+            applyOwnedEvent(forkId, event);
+          } else {
+            admission.events.push(event);
+          }
+          return;
+        }
+        applyOwnedEvent(forkId, event);
+      },
+      resolveReady,
+      rejectReady,
+    );
+    let disposed = false;
+    unsubscribeRef.current = () => {
+      if (disposed) return;
+      disposed = true;
+      unsubscribe();
+      // A send waiting for observation readiness must finish when the panel is
+      // disposed; its mounted check below then turns this into a clean no-op.
+      resolveReady();
+    };
+    return ready;
+  }, [applyOwnedEvent, mountedRef, resolveAdmission, sideChat]);
 
   const commitFork = useCallback(
     (session: SessionSummary) => {
@@ -262,7 +424,7 @@ export function useQuoteCompanion(input: UseQuoteCompanionInput): UseQuoteCompan
       companionIdRef.current = session.id;
       companionRef.current = session;
       setCompanion(session);
-      subscribeToFork(session.id);
+      subscriptionReadyRef.current = subscribeToFork(session.id);
     },
     [subscribeToFork],
   );
@@ -406,21 +568,43 @@ export function useQuoteCompanion(input: UseQuoteCompanionInput): UseQuoteCompan
       attachmentItems?: WorkbarIngestInput[],
     ): Promise<boolean> => {
       const trimmed = text.trim();
-      if (!mountedRef.current || !trimmed || turnInFlightRef.current || !sourceSession) {
+      if (
+        !mountedRef.current ||
+        !trimmed ||
+        submitLockRef.current ||
+        activeTurnIdRef.current ||
+        pendingAdmissionRef.current ||
+        !sourceSession
+      ) {
         return false;
       }
-      // Close the same-frame double-submit window before the first await. The
-      // visible in-flight state still begins only when the run is armed.
-      turnInFlightRef.current = true;
+      // Close the same-frame double-submit window before fork readiness can yield.
+      submitLockRef.current = true;
       setError(null);
       const turnId = crypto.randomUUID();
       const quoteSnapshot = snapshotCompanionQuotes(panelId, pendingQuotes);
       const label = (quoteSnapshot.quotes[0]?.text ?? trimmed).slice(0, 24);
       const fork = await ensureFork(`${copyRef.current.namePrefix}${label}`);
       if (fork.status !== 'ready') {
-        turnInFlightRef.current = false;
+        submitLockRef.current = false;
         return false;
       }
+      try {
+        await subscriptionReadyRef.current;
+      } catch {
+        if (mountedRef.current) {
+          unsubscribeRef.current?.();
+          subscriptionReadyRef.current = subscribeToFork(fork.session.id);
+          setError(copyRef.current.errors.sendFailed);
+        }
+        submitLockRef.current = false;
+        return false;
+      }
+      if (!mountedRef.current) {
+        submitLockRef.current = false;
+        return false;
+      }
+      let sendAdmission: PendingAdmission | undefined;
       const result = await performCompanionTurn({
         api: sideChat,
         sourceSession,
@@ -441,17 +625,37 @@ export function useQuoteCompanion(input: UseQuoteCompanionInput): UseQuoteCompan
         onForkCommitted: () => {},
         // Arm the optimistic live turn right before the send.
         onBeforeSend: () => {
-          stopRequestedRef.current = false;
-          activeTurnIdRef.current = turnId;
-          turnInFlightRef.current = true;
-          setTurnInFlight(true);
+          stopRequestRef.current = null;
+          const admission: PendingAdmission = {
+            messageId: turnId,
+            events: [],
+          };
+          sendAdmission = admission;
+          setPendingAdmission(admission);
+          submitLockRef.current = false;
           setLiveTurn(armLiveTurn(turnId));
-          ownTurnIdsRef.current.add(turnId);
-          setOwnTurnTick((tick) => tick + 1);
         },
         onQuotesConsumed: () => onQuotesConsumed(quoteSnapshot),
       });
-      if (result.status === 'sent') {
+      if (result.status === 'sent' || result.status === 'pending') {
+        const admission = sendAdmission;
+        if (!admission) return false;
+        if (result.status === 'pending') {
+          admission.consumeOnAdmission = () => onQuotesConsumed(quoteSnapshot);
+          const wasPending = pendingAdmissionRef.current === admission;
+          const outcome = resolveAdmission(result.forkId, admission, result.messageId);
+          if (outcome?.kind === 'admitted' && !wasPending) admission.consumeOnAdmission();
+          if (outcome?.kind === 'retracted') {
+            return false;
+          }
+        } else if (result.steered) {
+          if (resolveAdmission(result.forkId, admission, result.messageId)?.kind === 'retracted') {
+            return false;
+          }
+        } else {
+          bindAdmittedTurn(result.forkId, result.turnId);
+        }
+        if ((await admission.stopPromise) === 'confirmed') return false;
         setHasContent(true);
         // Surface the just-sent user message immediately, and reflect any
         // automatic connection/model rebound in the read-only model label.
@@ -485,12 +689,11 @@ export function useQuoteCompanion(input: UseQuoteCompanionInput): UseQuoteCompan
         };
         setError(byCode[result.code]);
         activeTurnIdRef.current = null;
-        turnInFlightRef.current = false;
-        setTurnInFlight(false);
+        if (sendAdmission) releaseAdmission(sendAdmission);
         setLiveTurn(undefined);
       }
       // 'disposed' → the panel unmounted mid-create; nothing to update.
-      turnInFlightRef.current = false;
+      submitLockRef.current = false;
       return false;
     },
     [
@@ -501,36 +704,108 @@ export function useQuoteCompanion(input: UseQuoteCompanionInput): UseQuoteCompan
       ensureFork,
       mountedRef,
       sideChat,
+      bindAdmittedTurn,
+      releaseAdmission,
+      resolveAdmission,
+      setPendingAdmission,
     ],
   );
 
   const stop = useCallback(async (): Promise<void> => {
     const id = companionIdRef.current;
-    if (!id) return;
-    stopRequestedRef.current = true;
+    if (!id || stopRequestRef.current) return;
+    const admission = pendingAdmissionRef.current;
+    if (admission) {
+      const stopPromise = sideChat.stop(id, admission.messageId).then(
+        (outcome) => {
+          if (
+            outcome?.kind === 'retracted' &&
+            outcome.messageId === admission.messageId
+          ) {
+            releaseAdmission(admission);
+          }
+          return 'confirmed' as const;
+        },
+        () => {
+          // A rejected Stop tells us nothing about whether the Host stopped
+          // the Turn. Keep the admission alive so a late Host outcome can
+          // still bind its own Turn; the user can retry Stop after this.
+          if (pendingAdmissionRef.current === admission) {
+            admission.stopPromise = undefined;
+            resolveAdmission(id, admission, admission.messageId, true);
+          }
+          if (stopRequestRef.current === stopPromise) stopRequestRef.current = null;
+          return 'unknown' as const;
+        },
+      );
+      admission.stopPromise = stopPromise;
+      stopRequestRef.current = stopPromise;
+      await stopPromise;
+      return;
+    }
+    const stopPromise = sideChat.stop(id, activeTurnIdRef.current ?? undefined);
+    stopRequestRef.current = stopPromise;
     try {
-      await sideChat.stop(id);
+      await stopPromise;
     } catch {
-      stopRequestedRef.current = false;
+      if (stopRequestRef.current === stopPromise) stopRequestRef.current = null;
       // best-effort; the terminal event still reconciles state
     }
-  }, [sideChat]);
+  }, [releaseAdmission, resolveAdmission, sideChat]);
 
   const steer = useCallback(async (text: string): Promise<boolean> => {
     const id = companionIdRef.current;
     const trimmed = text.trim();
-    if (!mountedRef.current || !id || !trimmed || !turnInFlight) return false;
+    if (
+      !mountedRef.current ||
+      !id ||
+      !trimmed ||
+      !turnInFlight ||
+      pendingAdmissionRef.current
+    ) {
+      return false;
+    }
+    const admissionId = crypto.randomUUID();
+    const admission: PendingAdmission = {
+      messageId: admissionId,
+      events: [],
+    };
+    setPendingAdmission(admission);
     try {
-      const outcome = await sideChat.steer(id, trimmed);
+      const outcome = await sideChat.steer(id, trimmed, admissionId);
       if (!mountedRef.current) return false;
-      if (outcome.kind !== 'queued') return false;
+      if ((await admission.stopPromise) === 'confirmed') return false;
+      if (admissionOutcomeForMessage(admission.events, admission.messageId)?.kind === 'retracted') {
+        return false;
+      }
+      if (outcome.kind === 'started') {
+        bindAdmittedTurn(id, outcome.turnId, { preserveLiveTurn: true });
+      } else if (resolveAdmission(id, admission, outcome.messageId, true)?.kind === 'retracted') {
+        return false;
+      }
       setError(null);
       return true;
     } catch {
-      if (mountedRef.current) setError(copyRef.current.errors.sendFailed);
+      if (mountedRef.current) {
+        if (pendingAdmissionRef.current === admission) {
+          releaseAdmission(admission, copyRef.current.errors.sendFailed);
+        } else if (
+          admissionOutcomeForMessage(admission.events, admission.messageId)?.kind !== 'retracted'
+        ) {
+          setError(copyRef.current.errors.sendFailed);
+        }
+      }
       return false;
     }
-  }, [mountedRef, sideChat, turnInFlight]);
+  }, [
+    bindAdmittedTurn,
+    mountedRef,
+    releaseAdmission,
+    resolveAdmission,
+    setPendingAdmission,
+    sideChat,
+    turnInFlight,
+  ]);
 
   const setPermissionMode = useCallback(
     async (mode: PermissionMode): Promise<boolean> => {
@@ -560,10 +835,8 @@ export function useQuoteCompanion(input: UseQuoteCompanionInput): UseQuoteCompan
       if (!id || turnInFlight || regeneratePendingTurnId) return false;
       setRegeneratePendingTurnId(turnId);
       const regenerationTurnId = crypto.randomUUID();
-      stopRequestedRef.current = false;
+      stopRequestRef.current = null;
       activeTurnIdRef.current = regenerationTurnId;
-      turnInFlightRef.current = true;
-      setTurnInFlight(true);
       setError(null);
       setLiveTurn(armLiveTurn(regenerationTurnId));
       ownTurnIdsRef.current.add(regenerationTurnId);
@@ -577,8 +850,6 @@ export function useQuoteCompanion(input: UseQuoteCompanionInput): UseQuoteCompan
       } catch {
         if (mountedRef.current) {
           activeTurnIdRef.current = null;
-          turnInFlightRef.current = false;
-          setTurnInFlight(false);
           setLiveTurn(undefined);
           setError(copyRef.current.errors.sendFailed);
         }
@@ -621,7 +892,6 @@ export function useQuoteCompanion(input: UseQuoteCompanionInput): UseQuoteCompan
   const messages = allMessages.filter(
     (message) => message.turnId !== undefined && ownTurnIdsRef.current.has(message.turnId),
   );
-  const { streaming, processing } = deriveCompanionComposerState(turnInFlight, liveTurn);
   // Inherited model (read-only): the fork's once created, else the source's.
   const activeModel = companion
     ? { llmConnectionSlug: companion.llmConnectionSlug, model: companion.model }
diff --git a/apps/desktop/src/renderer/platform/desktop/create-workbar-services.ts b/apps/desktop/src/renderer/platform/desktop/create-workbar-services.ts
index 86c9d0ef00..b3aebaa499 100644
--- a/apps/desktop/src/renderer/platform/desktop/create-workbar-services.ts
+++ b/apps/desktop/src/renderer/platform/desktop/create-workbar-services.ts
@@ -120,8 +120,12 @@ export function createDesktopWorkbarServices(
       abandonSessionCopy: (sourceSessionId, copyId) =>
         bridge.sessions.abandonSessionCopy(sourceSessionId, copyId),
       send: (sessionId, command) => bridge.sessions.send(sessionId, command),
-      stop: (sessionId) => bridge.sessions.stop(sessionId),
-      steer: (sessionId, text) => bridge.sessions.steer(sessionId, text),
+      stop: (sessionId, admissionId) =>
+        bridge.sessions.stop(
+          sessionId,
+          admissionId ? { source: 'stop_button', expectedAdmissionId: admissionId } : undefined,
+        ),
+      steer: (sessionId, text, admissionId) => bridge.sessions.steer(sessionId, text, admissionId),
       setPermissionMode: (sessionId, mode) =>
         bridge.sessions.setPermissionMode(sessionId, mode),
       regenerateTurn: (sessionId, input) =>
@@ -130,8 +134,8 @@ export function createDesktopWorkbarServices(
         bridge.sessions.respondToSandboxBoundary(sessionId, response),
       respondToUserQuestion: (sessionId, response) =>
         bridge.sessions.respondToUserQuestion(sessionId, response),
-      subscribeEvents: (sessionId, handler) =>
-        bridge.sessions.subscribeEvents(sessionId, handler),
+      subscribeEvents: (sessionId, handler, onSeeded, onSeedError) =>
+        bridge.sessions.subscribeEvents(sessionId, handler, onSeeded, undefined, onSeedError),
       subscribeSessionChanges: (handler) => bridge.sessions.subscribeChanges(handler),
     },
   };
diff --git a/apps/desktop/src/renderer/workhub-session-port.ts b/apps/desktop/src/renderer/workhub-session-port.ts
index 4d66344637..35558b5fab 100644
--- a/apps/desktop/src/renderer/workhub-session-port.ts
+++ b/apps/desktop/src/renderer/workhub-session-port.ts
@@ -68,7 +68,7 @@ export interface WorkHubDesktopSessionBridge {
   stop(
     sessionId: string,
     input?: { source?: 'stop_button'; expectedTurnId?: string },
-  ): Promise<void>;
+  ): Promise<unknown>;
   subscribeChanges(handler: () => void): () => void;
 }
 
diff --git a/apps/desktop/stories/session-workbar.stories.tsx b/apps/desktop/stories/session-workbar.stories.tsx
index 600fd6ebfa..8d80ea4879 100644
--- a/apps/desktop/stories/session-workbar.stories.tsx
+++ b/apps/desktop/stories/session-workbar.stories.tsx
@@ -709,9 +709,9 @@ function bridge(options: {
       branchFromTurn: async () => ({ ok: true, session: SIDE_CHAT_SESSION }),
       cleanupSessionCopy: async () => undefined,
       abandonSessionCopy: async () => undefined,
-      send: async () => ({ ok: true }),
+      send: async () => ({ ok: true, turnId: 'story-side-chat-turn' }),
       stop: async () => undefined,
-      steer: async () => ({ kind: 'queued' }),
+      steer: async () => ({ kind: 'started', turnId: 'story-side-chat-turn' }),
       setPermissionMode: async (_sessionId, mode) => ({
         ...SIDE_CHAT_SESSION,
         permissionMode: mode,
@@ -719,7 +719,10 @@ function bridge(options: {
       regenerateTurn: async () => undefined,
       respondToSandboxBoundary: async () => undefined,
       respondToUserQuestion: async () => undefined,
-      subscribeEvents: unsubscribe,
+      subscribeEvents: (_sessionId, _handler, onSeeded) => {
+        onSeeded?.();
+        return unsubscribe();
+      },
       subscribeSessionChanges: unsubscribe,
     },
   });
diff --git a/packages/cli/src/__tests__/runtime-host-run-command.test.ts b/packages/cli/src/__tests__/runtime-host-run-command.test.ts
index 94165620fc..3ba1fa5910 100644
--- a/packages/cli/src/__tests__/runtime-host-run-command.test.ts
+++ b/packages/cli/src/__tests__/runtime-host-run-command.test.ts
@@ -1554,6 +1554,7 @@ function continuitySnapshot(
     queue: { hostEpoch: 'host-1', queueRevision: 0, steering: [], followup: [] },
     interactions: { pending: [] },
     ...overrides,
+    rootTurnSourceMessageIds: overrides.rootTurnSourceMessageIds ?? [],
   };
 }
 
diff --git a/packages/cli/src/__tests__/runtime-host-session-driver.test.ts b/packages/cli/src/__tests__/runtime-host-session-driver.test.ts
index 1b9dc7abb1..37b5873595 100644
--- a/packages/cli/src/__tests__/runtime-host-session-driver.test.ts
+++ b/packages/cli/src/__tests__/runtime-host-session-driver.test.ts
@@ -1824,6 +1824,7 @@ function continuitySnapshot(
     queue: { hostEpoch: 'host-1', queueRevision: 0, steering: [], followup: [] },
     interactions: { pending: [] },
     ...overrides,
+    rootTurnSourceMessageIds: overrides.rootTurnSourceMessageIds ?? [],
   };
 }
 
diff --git a/packages/core/src/backend-types.ts b/packages/core/src/backend-types.ts
index 8990812e8b..46262ca9f2 100644
--- a/packages/core/src/backend-types.ts
+++ b/packages/core/src/backend-types.ts
@@ -191,6 +191,7 @@ export type BackendSessionEvent = Exclude<
     {
       type:
         | 'queue_update'
+        | 'message_admission'
         | 'permission_request'
         | 'permission_answer_ack'
         | 'permission_closure_ack'
diff --git a/packages/core/src/events.ts b/packages/core/src/events.ts
index 4a58287e49..bea135e5fd 100644
--- a/packages/core/src/events.ts
+++ b/packages/core/src/events.ts
@@ -486,6 +486,7 @@ export type SessionEvent =
   | PlanSubmittedEvent
   | TokenUsageEvent
   | SteeringMessageEvent
+  | MessageAdmissionEvent
   | QueueUpdateEvent
   | ProviderRetryEvent
   | ErrorEvent
@@ -1064,6 +1065,18 @@ export interface SteeringMessageEvent extends BaseEvent {
   submittedContentDigest?: `sha256:${string}`;
 }
 
+/**
+ * Transient Host projection fact: a submitted message now belongs to this
+ * Turn. It is emitted by the session projector, not by a backend or durable
+ * event ledger, so a client can bind a queued admission without guessing from
+ * timing or Turn ids returned by a stale command response.
+ */
+export interface MessageAdmissionEvent extends BaseEvent {
+  type: 'message_admission';
+  messageId: string;
+  outcome: 'admitted' | 'retracted';
+}
+
 /**
  * Result of enqueuing a steering / followup message. `fallback` means there was
  * no active run to attach to (the turn just ended) and the caller should open a
diff --git a/packages/runtime-host/src/__tests__/agent-graph-two-client-uds.test.ts b/packages/runtime-host/src/__tests__/agent-graph-two-client-uds.test.ts
index e05eb35488..44c1343bbe 100644
--- a/packages/runtime-host/src/__tests__/agent-graph-two-client-uds.test.ts
+++ b/packages/runtime-host/src/__tests__/agent-graph-two-client-uds.test.ts
@@ -365,6 +365,7 @@ function canonical(hostEpoch: string): CanonicalSessionProjection {
     goal: null,
     queue: { hostEpoch, queueRevision: 0, steering: [], followup: [] },
     interactions: { pending: [] },
+    rootTurnSourceMessageIds: [],
   };
 }
 
diff --git a/packages/runtime-host/src/__tests__/canonical-session-projection.test.ts b/packages/runtime-host/src/__tests__/canonical-session-projection.test.ts
index bb7a568554..742d9cd9d1 100644
--- a/packages/runtime-host/src/__tests__/canonical-session-projection.test.ts
+++ b/packages/runtime-host/src/__tests__/canonical-session-projection.test.ts
@@ -74,6 +74,7 @@ test('projects the canonical root lifecycle and the attachment queue from real S
       goal: null,
       queue: { hostEpoch: 'epoch-1', queueRevision: 0, steering: [], followup: [] },
       interactions: { pending: [] },
+      rootTurnSourceMessageIds: [],
     });
 
     const admitted = await rootAdmissions.admitRootTurn({
@@ -154,6 +155,51 @@ test('projects the canonical root lifecycle and the attachment queue from real S
   });
 });
 
+test('projects root admission source message tickets into continuity', async () => {
+  await withStores(async (root, stores) => {
+    const session = await stores.sessionStore.create(sessionInput(root));
+    const rootAdmissions = new RootAdmissionOwner(stores.agentRunStore);
+    await rootAdmissions.recoverSession(session.id);
+    const messages = createMessages(session.id, stores);
+    const reader = new CanonicalSessionProjectionReader({
+      stores,
+      rootAdmissions,
+      messages,
+    });
+    await rootAdmissions.admitRootTurn({
+      sessionId: session.id,
+      turnId: 'turn-successor',
+      proposedRunId: 'run-successor',
+      proposedUserMessageId: 'source-1',
+      execution: { kind: 'external_message' },
+      normalizedInput: { text: 'first\n\nsecond' },
+      sourceMessages: [
+        {
+          messageId: 'source-1',
+          content: { text: 'first' },
+          placement: 'current_turn',
+          disposition: 'steering',
+        },
+        {
+          messageId: 'source-2',
+          content: { text: 'second' },
+          placement: 'next_turn',
+          disposition: 'followup',
+        },
+      ],
+      admittedAt: 10,
+    });
+
+    const canonical = await reader.read(session.id);
+    assert.deepEqual(canonical?.rootTurnSourceMessageIds, ['source-1', 'source-2']);
+    assert.deepEqual(createSessionContinuitySnapshot(canonical!, 1).rootTurnSourceMessageIds, [
+      'source-1',
+      'source-2',
+    ]);
+    await messages.close();
+  });
+});
+
 test('projects pending Interactions and preflights their combined snapshot capacity', async () => {
   await withStores(async (root, stores) => {
     const session = await stores.sessionStore.create(sessionInput(root));
diff --git a/packages/runtime-host/src/__tests__/connection-session.test.ts b/packages/runtime-host/src/__tests__/connection-session.test.ts
index a80204812e..48020f9895 100644
--- a/packages/runtime-host/src/__tests__/connection-session.test.ts
+++ b/packages/runtime-host/src/__tests__/connection-session.test.ts
@@ -1436,6 +1436,7 @@ function canonicalProjection(sessionId: string): CanonicalSessionProjection {
       followup: [],
     },
     interactions: { pending: [] },
+    rootTurnSourceMessageIds: [],
   };
 }
 
diff --git a/packages/runtime-host/src/__tests__/goal-protocol.test.ts b/packages/runtime-host/src/__tests__/goal-protocol.test.ts
index f922dad0ce..519a7918b2 100644
--- a/packages/runtime-host/src/__tests__/goal-protocol.test.ts
+++ b/packages/runtime-host/src/__tests__/goal-protocol.test.ts
@@ -124,6 +124,7 @@ test('Goal projection is part of the exact Session continuity schema', () => {
     goal,
     queue: { hostEpoch: 'epoch-1', queueRevision: 0, steering: [], followup: [] },
     interactions: { pending: [] },
+    rootTurnSourceMessageIds: [],
   });
   assert.deepEqual(snapshot.goal, goal);
   assert.throws(() =>
diff --git a/packages/runtime-host/src/__tests__/protocol.test.ts b/packages/runtime-host/src/__tests__/protocol.test.ts
index c4f2fad83b..d5c8102105 100644
--- a/packages/runtime-host/src/__tests__/protocol.test.ts
+++ b/packages/runtime-host/src/__tests__/protocol.test.ts
@@ -295,6 +295,9 @@ describe('Runtime Host bootstrap protocol', () => {
         }),
       isInvalidFrame,
     );
+    const { rootTurnSourceMessageIds: _missing, ...missingAdmissionTickets } =
+      continuitySnapshot('epoch-1');
+    assert.throws(() => decodeSessionContinuitySnapshot(missingAdmissionTickets), isInvalidFrame);
     const waiting = {
       ...continuitySnapshot('epoch-1'),
       rootTurn: {
@@ -1796,5 +1799,6 @@ function continuitySnapshot(hostEpoch: string) {
       followup: [],
     },
     interactions: { pending: [] },
+    rootTurnSourceMessageIds: [],
   };
 }
diff --git a/packages/runtime-host/src/__tests__/session-continuity-coordinator.test.ts b/packages/runtime-host/src/__tests__/session-continuity-coordinator.test.ts
index 4ca2ec4d36..c3921be3a7 100644
--- a/packages/runtime-host/src/__tests__/session-continuity-coordinator.test.ts
+++ b/packages/runtime-host/src/__tests__/session-continuity-coordinator.test.ts
@@ -2078,6 +2078,7 @@ function canonical(
       followup: [],
     },
     interactions: overrides.interactions ?? { pending: [] },
+    rootTurnSourceMessageIds: [],
   };
 }
 
diff --git a/packages/runtime-host/src/__tests__/session-projector.test.ts b/packages/runtime-host/src/__tests__/session-projector.test.ts
index e2138d3f78..492b0967ee 100644
--- a/packages/runtime-host/src/__tests__/session-projector.test.ts
+++ b/packages/runtime-host/src/__tests__/session-projector.test.ts
@@ -19,6 +19,7 @@
 
 import assert from 'node:assert/strict';
 import test from 'node:test';
+import type { SessionEvent } from '@maka/core/events';
 import type { StoredMessage } from '@maka/core/session';
 import {
   createRuntimeHostSessionProjectionSeed,
@@ -72,6 +73,278 @@ test('applies authoritative replacement once and does not complete it again at T
   );
 });
 
+test('emits the Host admission fact when a queued message enters a successor Turn', () => {
+  const ordinary = new RuntimeHostSessionProjector(
+    withRootSourceMessageIds(snapshot(), ['ordinary-ticket']),
+    createRuntimeHostSessionProjectionSeed([], snapshot()),
+    () => 10,
+  );
+  assert.equal(
+    ordinary.seedActive(false).some((event) => event.type === 'message_admission'),
+    false,
+  );
+
+  const rejoined = new RuntimeHostSessionProjector(
+    withRootSourceMessageIds(snapshot(), ['rejoined-ticket']),
+    createRuntimeHostSessionProjectionSeed([], snapshot()),
+    () => 10,
+    [],
+    true,
+  );
+  assert.deepEqual(
+    rejoined
+      .seedActive(false)
+      .filter(
+        (event): event is Extract<SessionEvent, { type: 'message_admission' }> =>
+          event.type === 'message_admission' && event.outcome === 'admitted',
+      )
+      .map((event) => ({
+        turnId: event.turnId,
+        messageId: event.messageId,
+      })),
+    [{ turnId: 'turn-1', messageId: 'rejoined-ticket' }],
+  );
+
+  const previous = snapshot({
+    queue: {
+      hostEpoch: 'host-1',
+      queueRevision: 1,
+      steering: [
+        {
+          entryId: 'entry-1',
+          messageId: 'ticket-1',
+          content: { text: 'continue in successor' },
+          placement: 'current_turn',
+          state: 'queued',
+        },
+      ],
+      followup: [],
+    },
+  });
+  const projector = new RuntimeHostSessionProjector(
+    previous,
+    createRuntimeHostSessionProjectionSeed([], previous),
+    () => 10,
+    [],
+    true,
+  );
+  const next = withRootSourceMessageIds(
+    snapshot({
+      projectionRevision: 2,
+      queue: {
+        hostEpoch: 'host-1',
+        queueRevision: 2,
+        steering: [],
+        followup: [],
+      },
+      rootTurn: {
+        sessionId: 'session-1',
+        turnId: 'turn-2',
+        runId: 'run-2',
+        status: 'running',
+      },
+    }),
+    ['ticket-1'],
+  );
+
+  const events = projector.accept({
+    kind: 'subscription.session_projection',
+    hostEpoch: 'host-1',
+    subscriptionId: 'subscription-1',
+    sequence: 1,
+    snapshot: next,
+  }).events;
+
+  assert.deepEqual(
+    events
+      .filter((event) => event.type === 'message_admission' || event.type === 'queue_update')
+      .map((event) => event.type),
+    ['message_admission', 'queue_update'],
+  );
+
+  assert.deepEqual(
+    events
+      .filter(
+        (event): event is Extract<SessionEvent, { type: 'message_admission' }> =>
+          event.type === 'message_admission' && event.outcome === 'admitted',
+      )
+      .map((event) => ({
+        turnId: event.turnId,
+        messageId: event.messageId,
+      })),
+    [{ turnId: 'turn-2', messageId: 'ticket-1' }],
+  );
+
+  const retracted = new RuntimeHostSessionProjector(
+    previous,
+    createRuntimeHostSessionProjectionSeed([], previous),
+    () => 10,
+    [],
+    true,
+  ).accept({
+    kind: 'subscription.session_projection',
+    hostEpoch: 'host-1',
+    subscriptionId: 'subscription-1',
+    sequence: 1,
+    snapshot: snapshot({
+      projectionRevision: 2,
+      queue: next.queue,
+    }),
+  }).events;
+  assert.deepEqual(
+    retracted
+      .filter(
+        (event): event is Extract<SessionEvent, { type: 'message_admission' }> =>
+          event.type === 'message_admission' && event.outcome === 'retracted',
+      )
+      .map((event) => event.messageId),
+    ['ticket-1'],
+  );
+});
+
+test('emits the Host admission fact when a queued message enters the active Turn', () => {
+  const previous = snapshot({
+    queue: {
+      hostEpoch: 'host-1',
+      queueRevision: 1,
+      steering: [
+        {
+          entryId: 'entry-1',
+          messageId: 'ticket-1',
+          content: { text: 'continue here' },
+          placement: 'current_turn',
+          state: 'queued',
+        },
+      ],
+      followup: [],
+    },
+  });
+  const projector = new RuntimeHostSessionProjector(
+    previous,
+    createRuntimeHostSessionProjectionSeed([], previous),
+    () => 10,
+    [],
+    true,
+  );
+
+  const events = projector.accept({
+    kind: 'subscription.session_projection',
+    hostEpoch: 'host-1',
+    subscriptionId: 'subscription-1',
+    sequence: 1,
+    snapshot: snapshot({
+      projectionRevision: 2,
+      queue: {
+        hostEpoch: 'host-1',
+        queueRevision: 2,
+        steering: [
+          {
+            entryId: 'entry-1',
+            messageId: 'ticket-1',
+            content: { text: 'continue here' },
+            placement: 'current_turn',
+            state: 'in_flight',
+          },
+        ],
+        followup: [],
+      },
+    }),
+  }).events;
+
+  assert.deepEqual(
+    events
+      .filter(
+        (event): event is Extract<SessionEvent, { type: 'message_admission' }> =>
+          event.type === 'message_admission',
+      )
+      .map((event) => ({
+        outcome: event.outcome,
+        turnId: event.turnId,
+        messageId: event.messageId,
+      })),
+    [{ outcome: 'admitted', turnId: 'turn-1', messageId: 'ticket-1' }],
+  );
+});
+
+test('reseeds the Host admission fact for a message already in the active Turn', () => {
+  const current = snapshot({
+    queue: {
+      hostEpoch: 'host-1',
+      queueRevision: 2,
+      steering: [
+        {
+          entryId: 'entry-1',
+          messageId: 'ticket-1',
+          content: { text: 'continue here' },
+          placement: 'current_turn',
+          state: 'in_flight',
+        },
+      ],
+      followup: [],
+    },
+  });
+  const projector = new RuntimeHostSessionProjector(
+    current,
+    createRuntimeHostSessionProjectionSeed([], current),
+    () => 10,
+    [],
+    true,
+  );
+
+  assert.deepEqual(
+    projector
+      .seedActive(false)
+      .filter(
+        (event): event is Extract<SessionEvent, { type: 'message_admission' }> =>
+          event.type === 'message_admission',
+      )
+      .map((event) => ({
+        outcome: event.outcome,
+        turnId: event.turnId,
+        messageId: event.messageId,
+      })),
+    [{ outcome: 'admitted', turnId: 'turn-1', messageId: 'ticket-1' }],
+  );
+});
+
+test('reseeds the Host admission fact after an active Turn message leaves the queue', () => {
+  const current = snapshot();
+  const projector = new RuntimeHostSessionProjector(
+    current,
+    createRuntimeHostSessionProjectionSeed(
+      [
+        {
+          type: 'user',
+          id: 'ticket-1',
+          turnId: 'turn-1',
+          ts: 1,
+          text: 'continue here',
+          steeringEventId: 'steering-event-1',
+        },
+      ],
+      current,
+    ),
+    () => 10,
+    [],
+    true,
+  );
+
+  assert.deepEqual(
+    projector
+      .seedActive(false)
+      .filter(
+        (event): event is Extract<SessionEvent, { type: 'message_admission' }> =>
+          event.type === 'message_admission',
+      )
+      .map((event) => ({
+        outcome: event.outcome,
+        turnId: event.turnId,
+        messageId: event.messageId,
+      })),
+    [{ outcome: 'admitted', turnId: 'turn-1', messageId: 'ticket-1' }],
+  );
+});
+
 test('reseeds the latest provider retry when the active Turn still carries one', () => {
   const retry = {
     phase: 'scheduled' as const,
@@ -379,10 +652,18 @@ function snapshot(overrides: Partial<SessionContinuitySnapshot> = {}): SessionCo
       followup: [],
     },
     interactions: { pending: [] },
+    rootTurnSourceMessageIds: [],
     ...overrides,
   };
 }
 
+function withRootSourceMessageIds(
+  value: SessionContinuitySnapshot,
+  rootTurnSourceMessageIds: readonly string[],
+): SessionContinuitySnapshot {
+  return { ...value, rootTurnSourceMessageIds };
+}
+
 function assistant(id: string, text: string): Extract<StoredMessage, { type: 'assistant' }> {
   return {
     type: 'assistant',
diff --git a/packages/runtime-host/src/__tests__/session-subscription-client.test.ts b/packages/runtime-host/src/__tests__/session-subscription-client.test.ts
index dfe5d1bcab..40c0ef67f1 100644
--- a/packages/runtime-host/src/__tests__/session-subscription-client.test.ts
+++ b/packages/runtime-host/src/__tests__/session-subscription-client.test.ts
@@ -1255,6 +1255,7 @@ function openResult(
       goal: null,
       queue: { hostEpoch, queueRevision: 1, steering: [], followup: [] },
       interactions: { pending: [] },
+      rootTurnSourceMessageIds: [],
     },
   };
 }
diff --git a/packages/runtime-host/src/adapter/session-projector.ts b/packages/runtime-host/src/adapter/session-projector.ts
index 09760af34a..bb1618e4e2 100644
--- a/packages/runtime-host/src/adapter/session-projector.ts
+++ b/packages/runtime-host/src/adapter/session-projector.ts
@@ -42,7 +42,10 @@ interface AssistantAccumulator {
 }
 
 export interface RuntimeHostSessionProjectionSeed {
-  readonly durableInFlightMessageIds: readonly string[];
+  readonly durableSteeringMessages: readonly {
+    readonly messageId: string;
+    readonly turnId: string;
+  }[];
   readonly activeAssistantMessages: readonly Extract<StoredMessage, { type: 'assistant' }>[];
 }
 
@@ -50,13 +53,13 @@ export function createRuntimeHostSessionProjectionSeed(
   transcript: readonly StoredMessage[],
   snapshot: SessionContinuitySnapshot,
 ): RuntimeHostSessionProjectionSeed {
-  const inFlightMessageIds = new Set(
-    rootQueueInFlight(snapshot.queue).map((entry) => entry.messageId),
-  );
   return {
-    durableInFlightMessageIds: transcript
-      .filter((message) => inFlightMessageIds.has(message.id))
-      .map((message) => message.id),
+    durableSteeringMessages: transcript
+      .filter(
+        (message): message is Extract<StoredMessage, { type: 'user' }> =>
+          message.type === 'user' && message.steeringEventId !== undefined,
+      )
+      .map((message) => ({ messageId: message.id, turnId: message.turnId })),
     activeAssistantMessages:
       snapshot.rootTurn === null
         ? []
@@ -84,17 +87,24 @@ export class RuntimeHostSessionProjector {
   #snapshot: SessionContinuitySnapshot;
   readonly #now: () => number;
   readonly #transcriptIds: Set<string>;
+  readonly #durableSteeringTurnByMessage: ReadonlyMap<string, string>;
   readonly #accumulators = new Map<string, AssistantAccumulator>();
+  #projectMessageAdmissions: boolean;
 
   constructor(
     snapshot: SessionContinuitySnapshot,
     seed: RuntimeHostSessionProjectionSeed,
     now: () => number = Date.now,
     activeAssistantStreams: readonly SessionAssistantStreamIdentity[] = [],
+    projectMessageAdmissions = false,
   ) {
     this.#snapshot = structuredClone(snapshot);
     this.#now = now;
-    this.#transcriptIds = new Set(seed.durableInFlightMessageIds);
+    this.#durableSteeringTurnByMessage = new Map(
+      seed.durableSteeringMessages.map(({ messageId, turnId }) => [messageId, turnId]),
+    );
+    this.#transcriptIds = new Set(this.#durableSteeringTurnByMessage.keys());
+    this.#projectMessageAdmissions = projectMessageAdmissions;
     const root = snapshot.rootTurn;
     if (!root) return;
     for (const message of seed.activeAssistantMessages) {
@@ -139,10 +149,32 @@ export class RuntimeHostSessionProjector {
     return structuredClone(this.#snapshot);
   }
 
+  enableMessageAdmissions(): void {
+    this.#projectMessageAdmissions = true;
+  }
+
   seedActive(includeAssistantText: boolean): SessionEvent[] {
     const root = this.#snapshot.rootTurn;
-    if (!root || isRuntimeHostTerminalTurn(root)) return [];
+    if (!root) return [];
     const events: SessionEvent[] = [];
+    if (this.#projectMessageAdmissions) {
+      events.push(
+        ...projectMessageAdmissionEvents(
+          root,
+          [
+            ...new Set([
+              ...this.#snapshot.rootTurnSourceMessageIds,
+              ...rootQueueInFlight(this.#snapshot.queue).map((entry) => entry.messageId),
+              ...[...this.#durableSteeringTurnByMessage]
+                .filter(([, turnId]) => turnId === root.turnId)
+                .map(([messageId]) => messageId),
+            ]),
+          ],
+          this.#now(),
+        ),
+      );
+    }
+    if (isRuntimeHostTerminalTurn(root)) return events;
     let seededAssistantText = false;
     if (includeAssistantText) {
       for (const accumulator of this.#accumulators.values()) {
@@ -192,7 +224,12 @@ export class RuntimeHostSessionProjector {
   }
 
   seedTerminal(turn: RuntimeHostTerminalTurn): SessionEvent[] {
-    return this.#terminalEvents(turn, true);
+    return [
+      ...(this.#projectMessageAdmissions
+        ? projectMessageAdmissionEvents(turn, this.#snapshot.rootTurnSourceMessageIds, this.#now())
+        : []),
+      ...this.#terminalEvents(turn, true),
+    ];
   }
 
   seedStoredTerminal(turnId: string, transcript: readonly StoredMessage[]): SessionEvent[] {
@@ -356,8 +393,16 @@ export class RuntimeHostSessionProjector {
       events.push(...projectRuntimeHostInteractionRequest(interaction, this.#now()));
     }
     const root = next.rootTurn;
+    const enteredActiveTurn =
+      root && queueChanged(previousSnapshot.queue, next.queue)
+        ? newlyInFlight(previousSnapshot.queue, next.queue)
+        : [];
+    if (this.#projectMessageAdmissions) {
+      events.push(...projectMessageRetractionEvents(previousSnapshot, next, this.#now()));
+      events.push(...projectNewMessageAdmissionEvents(previousSnapshot, next, this.#now()));
+    }
     if (root && queueChanged(previousSnapshot.queue, next.queue)) {
-      for (const entry of newlyInFlight(previousSnapshot.queue, next.queue)) {
+      for (const entry of enteredActiveTurn) {
         events.push({
           type: 'steering_message',
           id: `host-queue:${next.queue.hostEpoch}:${next.queue.queueRevision}:${entry.entryId}`,
@@ -437,6 +482,67 @@ function emptyUpdate(events: readonly SessionEvent[]): RuntimeHostProjectionUpda
   return { events, resolvedInteractions: [] };
 }
 
+function projectMessageAdmissionEvents(
+  root: TurnSnapshot,
+  messageIds: readonly string[],
+  ts: number,
+): SessionEvent[] {
+  return messageIds.map((messageId) => ({
+    type: 'message_admission' as const,
+    id: `host-admission:${root.runId}:${messageId}`,
+    turnId: root.turnId,
+    ts,
+    messageId,
+    outcome: 'admitted' as const,
+  }));
+}
+
+function projectNewMessageAdmissionEvents(
+  previous: SessionContinuitySnapshot,
+  next: SessionContinuitySnapshot,
+  ts: number,
+): SessionEvent[] {
+  const root = next.rootTurn;
+  if (!root) return [];
+  const previousIds =
+    previous.rootTurn?.runId === root.runId
+      ? new Set(previous.rootTurnSourceMessageIds)
+      : new Set<string>();
+  const messageIds = new Set(
+    next.rootTurnSourceMessageIds.filter((messageId) => !previousIds.has(messageId)),
+  );
+  for (const entry of newlyInFlight(previous.queue, next.queue)) messageIds.add(entry.messageId);
+  return projectMessageAdmissionEvents(root, [...messageIds], ts);
+}
+
+function projectMessageRetractionEvents(
+  previous: SessionContinuitySnapshot,
+  next: SessionContinuitySnapshot,
+  ts: number,
+): SessionEvent[] {
+  const root = next.rootTurn ?? previous.rootTurn;
+  if (!root || previous.queue.hostEpoch !== next.queue.hostEpoch) return [];
+  const retained = new Set(
+    [...next.queue.steering, ...next.queue.followup].map((entry) => entry.messageId),
+  );
+  const admitted = new Set(next.rootTurnSourceMessageIds);
+  return [...previous.queue.steering, ...previous.queue.followup]
+    .filter(
+      (entry) =>
+        entry.state === 'queued' &&
+        !retained.has(entry.messageId) &&
+        !admitted.has(entry.messageId),
+    )
+    .map((entry) => ({
+      type: 'message_admission' as const,
+      id: `host-retraction:${next.queue.hostEpoch}:${next.queue.queueRevision}:${entry.messageId}`,
+      turnId: root.turnId,
+      ts,
+      messageId: entry.messageId,
+      outcome: 'retracted' as const,
+    }));
+}
+
 export function projectRuntimeHostInteractionRequest(
   interaction: InteractionPendingSnapshot,
   now: number,
diff --git a/packages/runtime-host/src/protocol/index.ts b/packages/runtime-host/src/protocol/index.ts
index 19d5dd1f5b..327dbfa347 100644
--- a/packages/runtime-host/src/protocol/index.ts
+++ b/packages/runtime-host/src/protocol/index.ts
@@ -91,7 +91,9 @@ export const RUNTIME_HOST_REGISTRATION_SCHEMA_VERSION = 1 as const;
 export const RUNTIME_HOST_PROTOCOL_VERSION = 0 as const;
 // Increment when the same protocol version no longer guarantees safe Client-Host
 // interoperability. Mismatches are rejected before domain commands are admitted.
-export const RUNTIME_HOST_COMPATIBILITY_EPOCH = 48 as const;
+export const RUNTIME_HOST_COMPATIBILITY_EPOCH = 49 as const;
+// 49: Session continuity snapshots carry Host-owned root source message
+// tickets so clients can bind queued admissions to successor Turns.
 // 48: Session branch creation accepts an explicit Side Conversation intent.
 // Older peers reject the strict input shape or cannot apply its snapshot semantics.
 // 47: Project registration can carry an explicit location preference. Epoch-46
diff --git a/packages/runtime-host/src/protocol/session-continuity.ts b/packages/runtime-host/src/protocol/session-continuity.ts
index c8ccb5055a..4a50f11f19 100644
--- a/packages/runtime-host/src/protocol/session-continuity.ts
+++ b/packages/runtime-host/src/protocol/session-continuity.ts
@@ -87,6 +87,8 @@ export interface SessionContinuitySnapshot {
   goal: GoalProjection | null;
   queue: SessionMessageQueueProjection;
   interactions: SessionInteractionProjection;
+  /** Host-owned source message tickets admitted into the root Turn. */
+  rootTurnSourceMessageIds: readonly string[];
 }
 
 export interface SubscriptionOpenInput {
@@ -515,7 +517,8 @@ export function decodeSessionContinuitySnapshot(value: unknown): SessionContinui
     'Session continuity snapshot',
     SESSION_CONTINUITY_SNAPSHOT_MAX_BYTES,
   );
-  const record = requireExactRecord(value, 'Session continuity snapshot', [
+  const record = requireRecord(value, 'Session continuity snapshot');
+  assertAllowedKeys(record, 'Session continuity snapshot', [
     'schemaVersion',
     'session',
     'projectionRevision',
@@ -523,6 +526,17 @@ export function decodeSessionContinuitySnapshot(value: unknown): SessionContinui
     'goal',
     'queue',
     'interactions',
+    'rootTurnSourceMessageIds',
+  ]);
+  assertRequiredKeys(record, 'Session continuity snapshot', [
+    'schemaVersion',
+    'session',
+    'projectionRevision',
+    'rootTurn',
+    'goal',
+    'queue',
+    'interactions',
+    'rootTurnSourceMessageIds',
   ]);
   if (record.schemaVersion !== SESSION_CONTINUITY_SCHEMA_VERSION) {
     throw invalidProtocolFrame('Unsupported Session continuity snapshot schema');
@@ -545,9 +559,17 @@ export function decodeSessionContinuitySnapshot(value: unknown): SessionContinui
     goal,
     queue: decodeSessionMessageQueueProjection(record.queue),
     interactions,
+    rootTurnSourceMessageIds: decodeRootTurnSourceMessageIds(record.rootTurnSourceMessageIds),
   };
 }
 
+function decodeRootTurnSourceMessageIds(value: unknown): string[] {
+  if (!Array.isArray(value)) throw invalidProtocolFrame('Invalid root Turn source message ids');
+  return value.map((messageId, index) =>
+    requireId(messageId, `root Turn source message id ${index}`),
+  );
+}
+
 function decodeSubscriptionOpenInput(value: unknown): SubscriptionOpenInput {
   const record = requireExactRecord(value, 'subscription.open input', ['sessionId', 'transcript']);
   const transcript = requireRecord(record.transcript, 'subscription transcript policy');
diff --git a/packages/runtime-host/src/server/canonical-session-projection.ts b/packages/runtime-host/src/server/canonical-session-projection.ts
index 2594acca4c..76cabef6ee 100644
--- a/packages/runtime-host/src/server/canonical-session-projection.ts
+++ b/packages/runtime-host/src/server/canonical-session-projection.ts
@@ -54,6 +54,7 @@ export interface CanonicalSessionProjection {
   readonly goal: GoalProjection | null;
   readonly queue: SessionMessageQueueProjection;
   readonly interactions: SessionInteractionProjection;
+  readonly rootTurnSourceMessageIds: readonly string[];
 }
 
 export interface CanonicalSessionProjectionCandidate {
@@ -98,6 +99,7 @@ export class CanonicalSessionProjectionReader {
     }
 
     let rootTurn: TurnSnapshot | null = null;
+    let rootTurnSourceMessageIds: readonly string[] = [];
     if (admission) {
       const durableAdmission = await this.#stores.agentRunStore.readRootTurnAdmission(
         sessionId,
@@ -108,6 +110,7 @@ export class CanonicalSessionProjectionReader {
       }
       this.#rootAdmissions.assertKnownAdmission(durableAdmission);
       rootTurn = await readCanonicalTurnSnapshot(this.#stores, durableAdmission);
+      rootTurnSourceMessageIds = durableAdmission.sourceMessages.map(({ messageId }) => messageId);
     }
 
     const interactions = projectSessionInteractions(
@@ -124,7 +127,14 @@ export class CanonicalSessionProjectionReader {
       createdAt: header.createdAt,
       isArchived: header.isArchived,
     };
-    return { session, rootTurn, goal, queue, interactions };
+    return {
+      session,
+      rootTurn,
+      goal,
+      queue,
+      interactions,
+      rootTurnSourceMessageIds,
+    };
   }
 
   async fitsCandidate(
@@ -192,6 +202,7 @@ function sessionContinuitySnapshotInput(
     goal: canonical.goal,
     queue: canonical.queue,
     interactions: canonical.interactions,
+    rootTurnSourceMessageIds: canonical.rootTurnSourceMessageIds,
   };
 }
 
diff --git a/packages/runtime/src/__tests__/session-event-runtime-mapper.test.ts b/packages/runtime/src/__tests__/session-event-runtime-mapper.test.ts
index bef67c4f58..045f94d21b 100644
--- a/packages/runtime/src/__tests__/session-event-runtime-mapper.test.ts
+++ b/packages/runtime/src/__tests__/session-event-runtime-mapper.test.ts
@@ -624,6 +624,24 @@ const projectionRunHeader: AgentRunHeader = {
 };
 
 describe('SessionEvent projection coverage', () => {
+  test('keeps Host admission facts out of durable Runtime events', () => {
+    assert.throws(
+      () =>
+        mapSessionEventToRuntimeEvent(
+          {
+            type: 'message_admission',
+            id: 'message-admission-1',
+            turnId: 'turn-1',
+            ts: 1,
+            messageId: 'message-1',
+            outcome: 'admitted',
+          },
+          ctx,
+        ),
+      /message_admission is not a backend event/,
+    );
+  });
+
   // The contract is over what a reader can actually meet: every mapped event
   // AgentRun admits to the ledger has to project. It asserts on the unclaimed
   // codes at either severity, not on the hard one alone — a control fact whose
diff --git a/packages/runtime/src/session-event-runtime-mapper.ts b/packages/runtime/src/session-event-runtime-mapper.ts
index e282d2e69e..3044d110f9 100644
--- a/packages/runtime/src/session-event-runtime-mapper.ts
+++ b/packages/runtime/src/session-event-runtime-mapper.ts
@@ -129,12 +129,10 @@ export function mapSessionEventToRuntimeEvent(
   ctx: RuntimeEventMapContext,
   memory: SessionEventMapMemory = createSessionEventMapMemory(),
 ): RuntimeEvent {
-  if (event.type === 'queue_update') {
-    // Not backend-mappable by design: the kernel is queue_update's only
-    // legal producer and pushes it directly into the turn stream. The flow
-    // drops a backend-yielded one at the ingress (see run()), so reaching
-    // this line means a caller bypassed that authority boundary.
-    throw new Error('queue_update is not a backend event: the kernel is its only legal producer');
+  if (event.type === 'queue_update' || event.type === 'message_admission') {
+    // These are Host/kernel projection facts, not backend events. The live
+    // ingress drops them, so reaching this line bypassed that authority boundary.
+    throw new Error(`${event.type} is not a backend event`);
   }
   if (isLegacyPermissionSessionEvent(event)) {
     throw new Error(`${event.type} is a legacy permission event and is not backend-mappable`);
@@ -144,7 +142,11 @@ export function mapSessionEventToRuntimeEvent(
 }
 
 export function isLiveBackendSessionEvent(event: SessionEvent): event is BackendSessionEvent {
-  return event.type !== 'queue_update' && !isLegacyPermissionSessionEvent(event);
+  return (
+    event.type !== 'queue_update' &&
+    event.type !== 'message_admission' &&
+    !isLegacyPermissionSessionEvent(event)
+  );
 }
 
 function isLegacyPermissionSessionEvent(event: SessionEvent): event is Extract<