diff --git a/apps/server/src/orchestration/Layers/ProviderCommandReactor.test.ts b/apps/server/src/orchestration/Layers/ProviderCommandReactor.test.ts
index c49646b7a4b..fe79696bcce 100644
--- a/apps/server/src/orchestration/Layers/ProviderCommandReactor.test.ts
+++ b/apps/server/src/orchestration/Layers/ProviderCommandReactor.test.ts
@@ -2174,6 +2174,144 @@ describe("ProviderCommandReactor", () => {
     expect(resolvedActivity).toBeUndefined();
   });
 
+  effectIt.effect(
+    "marks user-input responses stale when no provider session is bound to the thread",
+    () =>
+      Effect.gen(function* () {
+        const harness = yield* Effect.promise(() => createHarness());
+        const now = "2026-01-01T00:00:00.000Z";
+
+        yield* harness.engine.dispatch({
+          type: "thread.activity.append",
+          commandId: CommandId.make("cmd-user-input-requested-no-session"),
+          threadId: ThreadId.make("thread-1"),
+          activity: {
+            id: EventId.make("activity-user-input-requested-no-session"),
+            tone: "info",
+            kind: "user-input.requested",
+            summary: "User input requested",
+            payload: {
+              requestId: "user-input-request-1",
+              questions: [
+                {
+                  id: "fix_scope",
+                  header: "Fix scope",
+                  question: "How should I handle this?",
+                  options: [{ label: "Delete now", description: "Remove the garbage" }],
+                },
+              ],
+            },
+            turnId: null,
+            createdAt: now,
+          },
+          createdAt: now,
+        });
+
+        yield* harness.engine.dispatch({
+          type: "thread.user-input.respond",
+          commandId: CommandId.make("cmd-user-input-respond-no-session"),
+          threadId: ThreadId.make("thread-1"),
+          requestId: asApprovalRequestId("user-input-request-1"),
+          answers: {
+            fix_scope: "Delete now",
+          },
+          createdAt: now,
+        });
+
+        yield* Effect.promise(() =>
+          waitFor(async () => {
+            const readModel = await harness.readModel();
+            const thread = readModel.threads.find(
+              (entry) => entry.id === ThreadId.make("thread-1"),
+            );
+            return (
+              thread?.activities.some(
+                (activity) => activity.kind === "provider.user-input.respond.failed",
+              ) === true
+            );
+          }),
+        );
+
+        expect(harness.respondToUserInput).not.toHaveBeenCalled();
+
+        const readModel = yield* Effect.promise(() => harness.readModel());
+        const thread = readModel.threads.find((entry) => entry.id === ThreadId.make("thread-1"));
+        const failureActivity = thread?.activities.find(
+          (activity) => activity.kind === "provider.user-input.respond.failed",
+        );
+        const detail = (failureActivity?.payload as Record<string, unknown> | undefined)?.detail;
+        expect(failureActivity?.payload).toMatchObject({ requestId: "user-input-request-1" });
+        expect(detail).toContain("No active provider session is bound to this thread.");
+        // The stale marker is what every pending-request accounting keys off, so a
+        // dead session clears the prompt instead of leaving it answerable forever.
+        // Clearing itself is covered by session-logic / threadActivity tests.
+        expect(detail).toContain("Stale pending user-input request: user-input-request-1");
+      }),
+  );
+
+  effectIt.effect(
+    "marks approval responses stale when no provider session is bound to the thread",
+    () =>
+      Effect.gen(function* () {
+        const harness = yield* Effect.promise(() => createHarness());
+        const now = "2026-01-01T00:00:00.000Z";
+
+        yield* harness.engine.dispatch({
+          type: "thread.activity.append",
+          commandId: CommandId.make("cmd-approval-requested-no-session"),
+          threadId: ThreadId.make("thread-1"),
+          activity: {
+            id: EventId.make("activity-approval-requested-no-session"),
+            tone: "approval",
+            kind: "approval.requested",
+            summary: "Command approval requested",
+            payload: {
+              requestId: "approval-request-1",
+              requestKind: "command",
+            },
+            turnId: null,
+            createdAt: now,
+          },
+          createdAt: now,
+        });
+
+        yield* harness.engine.dispatch({
+          type: "thread.approval.respond",
+          commandId: CommandId.make("cmd-approval-respond-no-session"),
+          threadId: ThreadId.make("thread-1"),
+          requestId: asApprovalRequestId("approval-request-1"),
+          decision: "acceptForSession",
+          createdAt: now,
+        });
+
+        yield* Effect.promise(() =>
+          waitFor(async () => {
+            const readModel = await harness.readModel();
+            const thread = readModel.threads.find(
+              (entry) => entry.id === ThreadId.make("thread-1"),
+            );
+            return (
+              thread?.activities.some(
+                (activity) => activity.kind === "provider.approval.respond.failed",
+              ) === true
+            );
+          }),
+        );
+
+        expect(harness.respondToRequest).not.toHaveBeenCalled();
+
+        const readModel = yield* Effect.promise(() => harness.readModel());
+        const thread = readModel.threads.find((entry) => entry.id === ThreadId.make("thread-1"));
+        const failureActivity = thread?.activities.find(
+          (activity) => activity.kind === "provider.approval.respond.failed",
+        );
+        const detail = (failureActivity?.payload as Record<string, unknown> | undefined)?.detail;
+        expect(failureActivity?.payload).toMatchObject({ requestId: "approval-request-1" });
+        expect(detail).toContain("No active provider session is bound to this thread.");
+        expect(detail).toContain("Stale pending approval request: approval-request-1");
+      }),
+  );
+
   it("reacts to thread.session.stop by stopping provider session and clearing thread session state", async () => {
     const harness = await createHarness();
     const now = "2026-01-01T00:00:00.000Z";
diff --git a/apps/server/src/orchestration/Layers/ProviderCommandReactor.ts b/apps/server/src/orchestration/Layers/ProviderCommandReactor.ts
index 3044cc6029d..4490f77729f 100644
--- a/apps/server/src/orchestration/Layers/ProviderCommandReactor.ts
+++ b/apps/server/src/orchestration/Layers/ProviderCommandReactor.ts
@@ -166,6 +166,19 @@ function stalePendingRequestDetail(
   return `Stale pending ${requestKind} request: ${requestId}. Provider callback state does not survive app restarts or recovered sessions. Restart the turn to continue.`;
 }
 
+// A response can only reach the provider through the live session holding the
+// pending callback, so once that session is gone the request is permanently
+// unanswerable — exactly the stale-request case. Reuse the stale detail so the
+// pending accounting that keys off it (web/mobile derivePending*, the decider's
+// settle guard, ProjectionPipeline) clears the request instead of leaving an
+// answerable card that appends an identical failure on every submit.
+function noActiveSessionRequestDetail(
+  requestKind: "approval" | "user-input",
+  requestId: string,
+): string {
+  return `No active provider session is bound to this thread. ${stalePendingRequestDetail(requestKind, requestId)}`;
+}
+
 function buildGeneratedWorktreeBranchName(raw: string): string {
   const normalized = raw
     .trim()
@@ -929,7 +942,7 @@ const make = Effect.gen(function* () {
         threadId: event.payload.threadId,
         kind: "provider.approval.respond.failed",
         summary: "Provider approval response failed",
-        detail: "No active provider session is bound to this thread.",
+        detail: noActiveSessionRequestDetail("approval", event.payload.requestId),
         turnId: null,
         createdAt: event.payload.createdAt,
         requestId: event.payload.requestId,
@@ -973,7 +986,7 @@ const make = Effect.gen(function* () {
           threadId: event.payload.threadId,
           kind: "provider.user-input.respond.failed",
           summary: "Provider user input response failed",
-          detail: "No active provider session is bound to this thread.",
+          detail: noActiveSessionRequestDetail("user-input", event.payload.requestId),
           turnId: null,
           createdAt: event.payload.createdAt,
           requestId: event.payload.requestId,
diff --git a/apps/web/src/session-logic.test.ts b/apps/web/src/session-logic.test.ts
index 0f12e672f66..707f53ea7a0 100644
--- a/apps/web/src/session-logic.test.ts
+++ b/apps/web/src/session-logic.test.ts
@@ -307,6 +307,51 @@ describe("derivePendingUserInputs", () => {
 
     expect(derivePendingUserInputs(activities)).toEqual([]);
   });
+
+  it("clears pending user-input prompts once no provider session is bound to the thread", () => {
+    const activities: OrchestrationThreadActivity[] = [
+      makeActivity({
+        id: "user-input-open-no-session",
+        createdAt: "2026-02-23T00:00:01.000Z",
+        kind: "user-input.requested",
+        summary: "User input requested",
+        tone: "info",
+        payload: {
+          requestId: "req-user-input-no-session-1",
+          questions: [
+            {
+              id: "fix_scope",
+              header: "Fix scope",
+              question: "How should I handle this?",
+              options: [
+                {
+                  label: "Delete now",
+                  description: "Remove the garbage",
+                },
+              ],
+              multiSelect: false,
+            },
+          ],
+        },
+      }),
+      makeActivity({
+        id: "user-input-failed-no-session",
+        createdAt: "2026-02-23T00:00:02.000Z",
+        kind: "provider.user-input.respond.failed",
+        summary: "Provider user input response failed",
+        tone: "error",
+        payload: {
+          requestId: "req-user-input-no-session-1",
+          detail:
+            "No active provider session is bound to this thread. Stale pending user-input request: req-user-input-no-session-1. Provider callback state does not survive app restarts or recovered sessions. Restart the turn to continue.",
+        },
+      }),
+    ];
+
+    // The prompt's callback died with the session, so leaving the card
+    // answerable only lets every submit append another identical failure.
+    expect(derivePendingUserInputs(activities)).toEqual([]);
+  });
 });
 
 describe("deriveActivePlanState", () => {