feat(FN-5053): merge fusion/fn-5053 — align no-task heartbeat prompts

Squash-merge of fusion/fn-5053 (7 commits including retry duplicates).
Drops stale conflict in packages/core/src/index.ts (FN-5053 branch
re-exported symbols that main already exports) and packages/core/src/store.ts
(branch had a stale, narrower updateTask signature; main is authoritative).

Manual CEO recovery after the trailerless-commit attribution bug
(now fixed by FN-5090 in 92be8225e) stranded this task in in-review.

Fusion-Task-Id: FN-5053

packages/engine/src/__tests__/heartbeat-session-prompt.test.ts

@@ -13,6 +13,9 @@ import {
   HEARTBEAT_NO_TASK_SYSTEM_PROMPT,
   HEARTBEAT_PROCEDURE,
   HEARTBEAT_NO_TASK_PROCEDURE,
+  HEARTBEAT_NO_TASK_PROCEDURE_STRICT,
+  HEARTBEAT_NO_TASK_PROCEDURE_LITE,
+  HEARTBEAT_NO_TASK_PROCEDURE_OFF,
 } from "../agent-heartbeat.js";
 import { AgentLogger } from "../agent-logger.js";
 import * as agentTools from "../agent-tools.js";
@@ -97,9 +100,68 @@ describe("createHeartbeatTools", () => {
 
   it("heartbeat no-task system prompt documents coding-capable workspace access without task-scoped tools", () => {
     expect(HEARTBEAT_NO_TASK_SYSTEM_PROMPT).toContain("coding-capable workspace tools");
-    expect(HEARTBEAT_NO_TASK_SYSTEM_PROMPT).not.toContain("fn_task_document_write");
-    expect(HEARTBEAT_NO_TASK_SYSTEM_PROMPT).not.toContain("fn_task_document_read");
-    expect(HEARTBEAT_NO_TASK_SYSTEM_PROMPT).not.toContain("fn_task_log");
+  });
+
+  describe("FN-5053 no-task heartbeat prompt/tool alignment", () => {
+    const FORBIDDEN_NO_TASK_TOOLS = [
+      "fn_task_log",
+      "fn_task_document_write",
+      "fn_task_document_read",
+      "fn_task_update",
+      "fn_task_done",
+    ] as const;
+
+    const REQUIRED_NO_TASK_TOOLS = [
+      "fn_task_create",
+      "fn_list_agents",
+      "fn_delegate_task",
+      "fn_get_agent_config",
+      "fn_update_agent_config",
+      "fn_agent_create",
+      "fn_agent_delete",
+      "fn_send_message",
+      "fn_read_messages",
+      "fn_post_room_message",
+      "fn_memory_search",
+      "fn_memory_get",
+      "fn_memory_append",
+      "fn_web_fetch",
+      "fn_read_evaluations",
+      "fn_update_identity",
+      "fn_reflect_on_performance",
+      "fn_heartbeat_done",
+    ] as const;
+
+    const NO_TASK_PROMPT_VARIANTS = [
+      HEARTBEAT_NO_TASK_SYSTEM_PROMPT,
+      HEARTBEAT_NO_TASK_PROCEDURE_STRICT,
+      HEARTBEAT_NO_TASK_PROCEDURE_LITE,
+      HEARTBEAT_NO_TASK_PROCEDURE_OFF,
+    ] as const;
+
+    it.each(FORBIDDEN_NO_TASK_TOOLS)("FN-5053 excludes forbidden no-task tool reference %s", (toolName) => {
+      for (const promptText of NO_TASK_PROMPT_VARIANTS) {
+        expect(promptText).not.toContain(toolName);
+      }
+    });
+
+    it.each(REQUIRED_NO_TASK_TOOLS)("FN-5053 keeps required no-task tool in inventory: %s", (toolName) => {
+      expect(HEARTBEAT_NO_TASK_SYSTEM_PROMPT).toContain(toolName);
+    });
+
+    it("FN-5053 keeps no-task procedure persist-progress guidance on ambient tools", () => {
+      const expectedPersistLine = "fn_task_create, fn_delegate_task, fn_send_message, fn_memory_append.";
+      expect(HEARTBEAT_NO_TASK_PROCEDURE_STRICT).toContain(expectedPersistLine);
+      expect(HEARTBEAT_NO_TASK_PROCEDURE_LITE).toContain(expectedPersistLine);
+      expect(HEARTBEAT_NO_TASK_PROCEDURE_STRICT).toContain("fn_heartbeat_done");
+      expect(HEARTBEAT_NO_TASK_PROCEDURE_LITE).toContain("fn_heartbeat_done");
+      expect(HEARTBEAT_NO_TASK_PROCEDURE_OFF).toContain("fn_heartbeat_done");
+    });
+
+    it("FN-5053 keeps task-bound task-scoped guidance intact", () => {
+      expect(HEARTBEAT_SYSTEM_PROMPT).toContain("fn_task_log");
+      expect(HEARTBEAT_SYSTEM_PROMPT).toContain("fn_task_document_write");
+    });
   });
 
   it("returns task, delegation, and agent-config tools", () => {

packages/engine/src/agent-heartbeat.ts

@@ -422,7 +422,7 @@ Your job:
 3. Use fn_task_create to spawn follow-up work.
 4. Use fn_list_agents and fn_delegate_task to coordinate with other agents.
 5. Use fn_get_agent_config and fn_update_agent_config to read/tune direct-report agents for better routing outcomes.
-5. Call fn_heartbeat_done when finished with an optional summary of what was accomplished.
+6. Call fn_heartbeat_done when finished with an optional summary of what was accomplished.
 
 Examples of ONE useful action:
 - DO: create a clearly scoped task for a newly discovered reliability issue.
@@ -436,6 +436,10 @@ You have coding-capable workspace tools (read/write/edit/bash within worktree bo
 - fn_task_create
 - fn_list_agents and fn_delegate_task
 - fn_get_agent_config and fn_update_agent_config (for direct reports only)
+- fn_agent_create and fn_agent_delete (for direct reports only)
+- fn_read_evaluations and fn_update_identity (available in no-task runs)
+- fn_reflect_on_performance when reflection is enabled for this run
+- fn_web_fetch
 - fn_memory_search, fn_memory_get, and fn_memory_append
 - fn_heartbeat_done
 - fn_send_message, fn_read_messages, and fn_post_room_message when messaging/room tools are enabled for this run (they may not always be available)
@@ -2142,7 +2146,9 @@ export class HeartbeatMonitor {
         // For no-task runs, exclude fn_task_log and document tools (they require a taskId)
         let heartbeatTools: ToolDefinition[];
         if (isNoTaskRun) {
-          // No-task runs: fn_task_create, fn_list_agents, fn_delegate_task, fn_get_agent_config, fn_update_agent_config, messaging, memory, fn_heartbeat_done
+          // No-task runs: task creation/delegation, direct-report config + provisioning,
+          // optional messaging/room + reflection, evaluation/identity, web fetch,
+          // memory tools, and fn_heartbeat_done. Task-scoped tools are intentionally excluded.
           heartbeatTools = [];
 
           // fn_task_create tool