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+# Track test_harness_hardening_20260310 Context
+
+- [Specification](./spec.md)
+- [Implementation Plan](./plan.md)
+- [Metadata](./metadata.json)
diff --git a/conductor/tracks/test_harness_hardening_20260310/metadata.json b/conductor/tracks/test_harness_hardening_20260310/metadata.json
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+{
+  "track_id": "test_harness_hardening_20260310",
+  "type": "chore",
+  "status": "new",
+  "created_at": "2026-03-10T00:15:00Z",
+  "updated_at": "2026-03-10T00:15:00Z",
+  "description": "Hardening the Hook API and test harness to resolve port conflicts and state serialization issues."
+}
diff --git a/conductor/tracks/test_harness_hardening_20260310/plan.md b/conductor/tracks/test_harness_hardening_20260310/plan.md
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+# Implementation Plan: Hook API & Test Harness Hardening
+
+## Phase 1: Dynamic Port Allocation
+- [ ] Task: Modify `src/api_hooks.py` to attempt binding to port `8999`. If unsuccessful, iterate up to `9010`.
+- [ ] Task: Upon successful binding, write the selected port to a temporary artifact file (e.g., `.mcp_port`).
+- [ ] Task: Update the `live_gui` fixture in `tests/conftest.py` to read the assigned port from the artifact file and use it for all `ApiHookClient` requests.
+- [ ] Task: Conductor - User Manual Verification 'Phase 1: Dynamic Port Allocation' (Protocol in workflow.md)
+
+## Phase 2: Graceful Teardown
+- [ ] Task: Implement a `/api/shutdown` POST endpoint in `src/api_hooks.py`.
+- [ ] Task: Ensure the `/api/shutdown` endpoint correctly signals the `AppController` and `App` to perform a clean exit (e.g., joining threads, writing pending saves).
+- [ ] Task: Update the `live_gui` fixture to call `/api/shutdown` during teardown, relying on `taskkill` only as a last resort if the process fails to exit gracefully within a timeout.
+- [ ] Task: Conductor - User Manual Verification 'Phase 2: Graceful Teardown' (Protocol in workflow.md)
+
+## Phase 3: State Serialization Audit
+- [ ] Task: Audit `src/app_controller.py` to identify all GUI-related state variables that should be exposed to tests (e.g., `show_windows`, individual window toggles).
+- [ ] Task: Update `_gettable_fields` to ensure all necessary state is mapped.
+- [ ] Task: Refine `_serialize_for_api` in `src/api_hooks.py` (or introduce lightweight dataclass parsing) to handle complex nested objects predictably.
+- [ ] Task: Conductor - User Manual Verification 'Phase 3: State Serialization Audit' (Protocol in workflow.md)
+
+## Phase 4: Verification
+- [ ] Task: Write Tests: Create a concurrency test verifying multiple `live_gui` instances can launch simultaneously without port conflicts.
+- [ ] Task: Run the entire test suite to ensure the new dynamic port and graceful shutdown logic has not introduced regressions.
+- [ ] Task: Conductor - User Manual Verification 'Phase 4: Verification' (Protocol in workflow.md)
diff --git a/conductor/tracks/test_harness_hardening_20260310/spec.md b/conductor/tracks/test_harness_hardening_20260310/spec.md
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+# Specification: Hook API & Test Harness Hardening
+
+## Overview
+This track focuses on stabilizing the local development and testing environment by hardening the Hook API and its associated `live_gui` test harness. The goal is to eliminate port conflicts, ensure graceful teardowns, and standardize state serialization, laying the groundwork for a future WebSockets implementation.
+
+## Functional Requirements
+- **Dynamic Port Allocation:**
+  - The Hook Server (`src/api_hooks.py`) will implement a Sequential Fallback strategy for port binding.
+  - It will attempt to bind to port `8999`. If `Address already in use` is encountered, it will sequentially try ports up to `9010` until successful.
+  - The successfully bound port will be written to a temporary artifact file (e.g., `.mcp_port` or similar) so the test harness can discover it.
+- **Graceful Teardown:**
+  - Implement a new `/api/shutdown` POST endpoint in the Hook API.
+  - When called, this endpoint should safely signal the `AppController` and `App` to initiate a clean shutdown (joining threads, closing files) rather than relying on the OS to forcefully kill the process tree.
+  - Update the `live_gui` fixture to call this endpoint during the `finally` block before resorting to `taskkill` as a last-resort fallback.
+- **State Serialization Audit:**
+  - Formalize the structure returned by `/api/gui/state`. 
+  - Ensure all fields defined in `_gettable_fields` are safely serialized using standard dataclass/dict traversal (avoiding deep Pydantic dependencies for now, keeping it lightweight but strictly typed for future WebSocket pipeline compatibility).
+  - Add missing fields discovered during recent UI tracks (e.g., `show_windows` states).
+
+## Non-Functional Requirements
+- **Stability:** The `live_gui` fixture must pass 100% of the time without port conflict errors when tests are run sequentially.
+- **Performance:** The port scanning logic should fail fast and bind within milliseconds.
+
+## Acceptance Criteria
+- [ ] A test script can successfully launch two concurrent `live_gui` instances, and they bind to different ports.
+- [ ] Calling `/api/shutdown` successfully stops the GUI process and returns a 200 OK.
+- [ ] The `live_gui` fixture uses the shutdown endpoint and the test suite passes without leaving orphaned processes.
+- [ ] The state returned by `/api/gui/state` is fully documented and includes all relevant nested objects (like `show_windows`).
+
+## Out of Scope
+- Implementing the WebSockets streaming logic (this track only prepares the state schema for it).
+- Fixing failing simulation tests that are unrelated to the harness itself.