# MACP Phase 1 — Core Protocol Implementation

**Branch:** `feat/macp-phase1`
**Repo:** `mosaic-bootstrap` (worktree at `~/src/mosaic-bootstrap-worktrees/macp-phase1`)

---

## Objective

Extend the existing orchestrator-matrix into **MACP (Mosaic Agent Coordination Protocol)** — a standardized protocol that lets any orchestrator delegate work to any agent runtime, track progress via quality gates, and collect structured results.

This is an **evolution** of the existing code, not a rewrite. Extend existing schemas, enhance the controller, and add the dispatcher layer.

---

## Task 1: Extend Task Schema (`tools/orchestrator-matrix/protocol/task.schema.json`)

Add these new fields to the existing schema:

```json
{
  "type": {
    "type": "string",
    "enum": ["coding", "deploy", "research", "review", "documentation", "infrastructure"],
    "description": "Task type — determines dispatch strategy and gate requirements"
  },
  "dispatch": {
    "type": "string",
    "enum": ["yolo", "acp", "exec"],
    "description": "Execution backend: yolo=mosaic yolo (full system), acp=OpenClaw sessions_spawn (sandboxed), exec=direct shell"
  },
  "worktree": {
    "type": "string",
    "description": "Path to git worktree for this task, e.g. ~/src/repo-worktrees/task-042"
  },
  "branch": {
    "type": "string",
    "description": "Git branch name for this task"
  },
  "brief_path": {
    "type": "string",
    "description": "Path to markdown task brief relative to repo root"
  },
  "result_path": {
    "type": "string",
    "description": "Path to JSON result file relative to .mosaic/orchestrator/"
  },
  "issue": {
    "type": "string",
    "description": "Issue reference (e.g. #42)"
  },
  "pr": {
    "type": ["string", "null"],
    "description": "PR number/URL once opened"
  },
  "depends_on": {
    "type": "array",
    "items": { "type": "string" },
    "description": "List of task IDs this task depends on"
  },
  "max_attempts": {
    "type": "integer",
    "minimum": 1,
    "default": 1
  },
  "attempts": {
    "type": "integer",
    "minimum": 0,
    "default": 0
  },
  "timeout_seconds": {
    "type": "integer",
    "description": "Override default timeout for this task"
  }
}
```

Extend the `status` enum to include: `"pending"`, `"running"`, `"gated"`, `"completed"`, `"failed"`, `"escalated"`

Keep all existing fields. Keep `additionalProperties: true`.

---

## Task 2: Extend Event Schema (`tools/orchestrator-matrix/protocol/event.schema.json`)

Add new event types to the enum:
- `task.gated` — Worker done coding, quality gates now running
- `task.escalated` — Requires human intervention
- `task.retry.scheduled` — Task will be retried (already emitted by controller, just not in schema)

Add new source type: `"dispatcher"`

Keep all existing event types and fields.

---

## Task 3: Create Result Schema (`tools/orchestrator-matrix/protocol/result.schema.json`)

New file — standardized worker completion report:

```json
{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://mosaicstack.dev/schemas/orchestrator/result.schema.json",
  "title": "MACP Task Result",
  "type": "object",
  "required": ["task_id", "status", "completed_at"],
  "properties": {
    "task_id": { "type": "string" },
    "status": { "type": "string", "enum": ["completed", "failed", "escalated"] },
    "completed_at": { "type": "string", "format": "date-time" },
    "failed_at": { "type": ["string", "null"], "format": "date-time" },
    "exit_code": { "type": ["integer", "null"] },
    "attempt": { "type": "integer" },
    "max_attempts": { "type": "integer" },
    "runtime": { "type": "string" },
    "dispatch": { "type": "string" },
    "worktree": { "type": ["string", "null"] },
    "branch": { "type": ["string", "null"] },
    "pr": { "type": ["string", "null"] },
    "summary": { "type": "string", "description": "Human-readable summary of what the worker did" },
    "files_changed": { "type": "array", "items": { "type": "string" } },
    "gate_results": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "command": { "type": "string" },
          "exit_code": { "type": "integer" },
          "type": { "type": "string", "enum": ["mechanical", "ai-review", "ci-pipeline"] }
        }
      }
    },
    "error": { "type": ["string", "null"] },
    "escalation_reason": { "type": ["string", "null"] },
    "metadata": { "type": "object" }
  }
}
```

---

## Task 4: Build MACP Dispatcher (`tools/orchestrator-matrix/dispatcher/macp_dispatcher.py`)

New Python module — the core of MACP. This translates task specs into execution commands and manages the full lifecycle.

### Dispatcher Responsibilities:
1. **Worktree setup** — `git worktree add` before dispatch (if task has `worktree` field)
2. **Command generation** — Build the right command based on `dispatch` type:
   - `yolo`: `mosaic yolo codex|claude|opencode "<brief contents>"` (reads from `brief_path`)
   - `acp`: Generates a command that would be used with OpenClaw sessions_spawn (just outputs the config JSON for the caller)
   - `exec`: Direct shell command from task `command` field
3. **Result collection** — After worker exits, write structured result JSON to `results/<task-id>.json`
4. **Worktree cleanup** — After task completion (success or failure after max retries), remove the worktree

### Key Functions:

```python
def setup_worktree(task: dict, repo_root: Path) -> Path:
    """Create git worktree for task. Returns worktree path."""
    
def build_dispatch_command(task: dict, repo_root: Path) -> str:
    """Generate execution command based on task dispatch type and runtime."""
    
def collect_result(task: dict, exit_code: int, gate_results: list, orch_dir: Path) -> dict:
    """Build standardized result JSON after worker completion."""
    
def cleanup_worktree(task: dict) -> None:
    """Remove git worktree after task is done."""
    
def dispatch_task(task: dict, repo_root: Path, orch_dir: Path, config: dict) -> tuple[int, str]:
    """Full dispatch lifecycle: setup → execute → collect → cleanup. Returns (exit_code, output)."""
```

### Worktree Convention:
- Base path: `~/src/<repo-name>-worktrees/`
- Worktree name: task ID slugified (e.g., `task-042-auth`)
- Branch: `feat/<task-id>-<slugified-title>` (or use task `branch` field if specified)
- Created from: `origin/main`

### `mosaic yolo` Command Pattern:
The dispatcher needs to invoke `mosaic yolo` via PTY (it requires a terminal). The command pattern:
```bash
export PATH="$HOME/.config/mosaic/bin:$PATH"
cd <worktree_path>
mosaic yolo codex "<task brief contents>"
```

For the dispatcher, since it's called from the controller which uses `subprocess.Popen`, the command should be wrapped appropriately. Use `script -qec` or similar for PTY simulation if needed, but prefer passing the brief via a temp file and using the worker script pattern.

### Important Constraints:
- The dispatcher is a **library module** imported by the controller — NOT a standalone script
- It should be testable (pure functions where possible, side effects isolated)
- Error handling: if worktree creation fails, task goes to `failed` immediately
- If `dispatch` is not set on a task, fall back to `exec` (backward compatible)
- If `runtime` is not set, fall back to config's `worker.runtime`

---

## Task 5: Wire Controller to Use Dispatcher (`tools/orchestrator-matrix/controller/mosaic_orchestrator.py`)

Modify the existing controller to use the new dispatcher:

1. **Import the dispatcher module**
2. **In `run_single_task()`**: 
   - If task has `dispatch` field (or is MACP-aware), call `dispatcher.dispatch_task()` instead of raw `run_shell()`
   - If task does NOT have `dispatch` field, keep existing `run_shell()` behavior (backward compatibility)
3. **Handle new statuses**: `gated` and `escalated`
   - `gated`: Set when worker completes but gates are running (transition state between running and completed/failed)
   - `escalated`: Set when task needs human intervention (gate failures after max retries, explicit worker escalation)
4. **Emit new event types**: `task.gated` and `task.escalated`

### Backward Compatibility is Critical:
- Existing tasks.json files with no `dispatch` field MUST continue to work exactly as before
- The controller should detect MACP-aware tasks by checking for the `dispatch` field
- All existing tests/workflows must remain functional

---

## Task 6: Update Config Template (`templates/repo/.mosaic/orchestrator/config.json`)

Add MACP dispatcher configuration:

```json
{
  "enabled": false,
  "transport": "matrix",
  "macp": {
    "worktree_base": "~/src/{repo}-worktrees",
    "default_dispatch": "exec",
    "default_runtime": "codex",
    "cleanup_worktrees": true,
    "brief_dir": "docs/tasks",
    "result_dir": ".mosaic/orchestrator/results"
  },
  "worker": { ... existing ... },
  "quality_gates": [ ... existing ... ]
}
```

---

## Task 7: Build `mosaic macp` CLI (`bin/mosaic-macp`)

Shell script that provides manual MACP interaction:

```bash
mosaic macp submit --task-id TASK-001 --title "..." --type coding --runtime codex --brief docs/tasks/TASK-001.md
mosaic macp status [--task-id TASK-001]
mosaic macp drain                    # Run all pending tasks sequentially
mosaic macp history [--task-id TASK-001]  # Show events for a task
```

Implementation:
- `submit`: Adds a task to `tasks.json` with MACP fields populated
- `status`: Pretty-prints task queue state (pending/running/gated/completed/failed/escalated counts)
- `drain`: Calls `mosaic-orchestrator-run --until-drained`
- `history`: Reads `events.ndjson` and filters by task ID

Register in the main `bin/mosaic` dispatcher so `mosaic macp ...` works.

---

## Task 8: Update `tasks_md_sync.py`

Extend the sync script to handle MACP-specific columns in `docs/TASKS.md`:

Optional new columns: `type`, `dispatch`, `runtime`, `branch`

If these columns exist in the markdown table, map them to the task JSON. If they don't exist, use defaults from config.

---

## Verification

After all tasks are complete:

1. **Existing behavior preserved**: Run `python3 tools/orchestrator-matrix/controller/mosaic_orchestrator.py --repo /tmp/test-repo --once` with an old-style tasks.json — must work identically
2. **New MACP flow works**: Create a tasks.json with `dispatch: "exec"` tasks, run controller, verify worktree creation, execution, result collection, and cleanup
3. **Schema validation**: All JSON files should validate against their schemas
4. **CLI works**: `mosaic macp status` and `mosaic macp submit` produce correct output
5. **No broken imports**: All Python files should pass `python3 -c "import ..."`

---

## File Map (what goes where)

```
tools/orchestrator-matrix/
├── protocol/
│   ├── task.schema.json          ← MODIFY (extend)
│   ├── event.schema.json         ← MODIFY (extend)
│   └── result.schema.json        ← NEW
├── dispatcher/
│   ├── __init__.py               ← NEW
│   └── macp_dispatcher.py        ← NEW
├── controller/
│   ├── mosaic_orchestrator.py    ← MODIFY (wire dispatcher)
│   └── tasks_md_sync.py         ← MODIFY (new columns)
├── transport/
│   └── matrix_transport.py       ← UNCHANGED
└── adapters/
    └── README.md                 ← UNCHANGED

templates/repo/.mosaic/orchestrator/
├── config.json                   ← MODIFY (add macp section)
├── tasks.json                    ← UNCHANGED
└── ...

bin/
├── mosaic                        ← MODIFY (add macp subcommand routing)
└── mosaic-macp                   ← NEW
```

---

## Ground Rules

- This is the `mosaic-bootstrap` repo — a CLI framework, NOT a web app
- No npm/pnpm — this is bash + Python (stdlib only, no pip dependencies)
- All Python must work with Python 3.10+
- Keep the deterministic controller pattern — no async, no threads, no external services
- Commit messages: `feat: <what changed>` (conventional commits)
- Push to `feat/macp-phase1` branch when done