fix(prompts): forbid tool-less status turns and seed idle-with-fleet false

Author: TheGreatAxios

packages/prompt-fragments/src/cards.ts

@@ -19,6 +19,7 @@ ${dispatchRouteSection()}
 - Read only enough to route and write a useful brief. Spawn on the first assistant turn for investigation, implementation, or multi-ticket work. Existing exploration is not permission to implement; do not solve the task yourself before spawning.
 
 # Rules
+- A reply with no tool calls ends the turn — never emit a standalone status announcement before spawning; include \`spawn_agent\` (or the next tool call) in the same turn as your status line.
 - Edit files with file tools only, never shell redirection or sed.
 - Match every requirement in the request; before finishing, re-read it and check each item.
 - Use manage_tasks for work of three or more steps.

src/prompts.test.ts

@@ -34,6 +34,14 @@ test("dispatch card is spawn-first with no parallelization cap", () => {
   expect(prompt).not.toMatch(/single explorer worker/i);
 });
 
+test("dispatch card forbids tool-less status announcements before spawning", () => {
+  const prompt = buildChatSystemPrompt();
+  expect(prompt).toMatch(/reply with no tool calls ends the turn/i);
+  expect(prompt).toMatch(
+    /never emit a standalone status announcement before spawning/i,
+  );
+});
+
 const envBase: EnvironmentInfo = {
   cwd: "/tmp/proj",
   platform: "test",

src/tui/runner/exit.test.ts

@@ -590,8 +590,9 @@ function rebuildManageTasksEvent(): ReactorInboundEvent {
 /**
  * The services surface every rebuild path touches: holder swap, fleet store,
  * workflow reattach, recorder reset, and a buildAgent that mints a fresh
- * director from the static `allowIdleWithFleet: true` seed — the same seed
- * the TUI session assembly uses (fleet lanes may appear mid-session). The
+ * director from the static `allowIdleWithFleet: false` seed — the same seed
+ * the TUI session assembly uses (0 workers run at build time; `resyncIdleWithFleetFlag`
+ * re-syncs from `liveFleetCount(...) > 0` across rebuilds). The
  * rotation-only stubs (buildSessionSources, hostHolder, the resetters) are
  * inert on interrupt/reload paths.
  */
@@ -639,7 +640,7 @@ function wireRebuildServices(
   services.hostHolder = {} as unknown as RunnerServices["hostHolder"];
   services.buildAgent = (async () => {
     directorHolder.instance = createChatDirector("base", [], {
-      allowIdleWithFleet: true,
+      allowIdleWithFleet: false,
     });
     return agent;
   }) as unknown as RunnerServices["buildAgent"];
@@ -661,7 +662,7 @@ async function expectOpenTaskNudge(director: ChatDirector): Promise<void> {
   expect(list.some((action) => action.type === "infer")).toBe(true);
 }
 
-describe("rebuild re-syncs idle-with-fleet while drained", () => {
+describe("rebuild re-syncs idle-with-fleet while drained or live", () => {
   test("seed then fleet-0 does not leave idle-with-fleet stuck true", async () => {
     const store = createSubAgentSessionStore();
     const director = createChatDirector("base", [], {
@@ -674,6 +675,43 @@ describe("rebuild re-syncs idle-with-fleet while drained", () => {
     await expectOpenTaskNudge(director);
   });
 
+  test("false seed with no running lanes nudges open tasks without waiting for a resync", async () => {
+    const director = createChatDirector("base", [], {
+      allowIdleWithFleet: false,
+    });
+    await expectOpenTaskNudge(director);
+  });
+
+  test("resyncIdleWithFleetFlag promotes false seed to true when a fleet lane is running", async () => {
+    const store = createSubAgentSessionStore();
+    store.start({
+      id: "lane-1",
+      description: "work",
+      agentId: "coder",
+      brief: "implement",
+    });
+    const director = createChatDirector("base", [], {
+      allowIdleWithFleet: false,
+    });
+    resyncIdleWithFleetFlag({
+      directorHolder: { instance: director },
+      subAgentSessions: store,
+    });
+    await director.decide(
+      rebuildManageTasksEvent(),
+      stubReactorState,
+      stubReactorCapabilities,
+    );
+    const actions = await director.decide(
+      stubTextTurnEvent(),
+      stubReactorState,
+      stubReactorCapabilities,
+    );
+    const list = Array.isArray(actions) ? actions : [actions];
+    expect(list.some((action) => action.type === "infer")).toBe(false);
+    expect(list.some((action) => action.type === "reply")).toBe(true);
+  });
+
   test("first assemble with a drained fleet does not leave idle-with-fleet stuck true", async () => {
     const store = createSubAgentSessionStore();
     const directorHolder: RunnerServices["directorHolder"] = {};

src/tui/runner/exit.ts

@@ -152,9 +152,10 @@ type AgentBuildReason =
   | "interrupt"
   | "session-rotation";
 
-// Directors seed allowIdleWithFleet=true because fleet lanes may appear
-// mid-session. Rebuilds re-sync from the live count: the publisher only
-// fires on a count change, so a session that never sees 0→1→0 keeps the seed.
+// Session assembly seeds allowIdleWithFleet=false because zero workers run at
+// startup. Mid-session rebuilds (interrupt, reloadIfIdle, rotation) mint a
+// fresh director from that static false seed while the publisher only fires on
+// fleet-count transitions, so rebuilds re-sync from liveFleetCount(...) > 0.
 export function resyncIdleWithFleetFlag(
   services: Pick<RunnerServices, "directorHolder" | "subAgentSessions">,
 ): void {

src/tui/runner/session.ts

@@ -718,12 +718,11 @@ export async function assembleTUISession(
     computeAdvertised,
     inactivityTimeoutMs: config.inactivityTimeoutMs ?? 750_000,
     totalTimeoutMs: config.totalTimeoutMs,
-    // Seed the idle-with-fleet allowance (fleet lanes may appear mid-session;
-    // the fleet-wake publisher keeps it live). No onTasksChange /
-    // requestContinuation / getLiveFleetCount closures: task/tool updates and
-    // compaction re-entry arrive as reactor events in the stream sink, and
-    // the publisher drives the allowance via setAllowIdleWithFleet.
-    allowIdleWithFleet: true,
+    // Seed false at construction because zero workers run at initial session
+    // assembly; the fleet-wake publisher flips it true when running > 0 and
+    // back to false when running === 0, while resyncIdleWithFleetFlag re-syncs
+    // from liveFleetCount(...) > 0 across mid-session rebuilds.
+    allowIdleWithFleet: false,
     clearDenials: () => permissionGate.clearDenials(),
     getProvider: () => state.config,
     directorHolder,