/maestro-fork

name: maestro-fork
disable-model-invocation: true
description: Create or sync session worktree for parallel dev
argument-hint: "--session <session_id> [--base <ref>] [--sync]"
allowed-tools:
  - Read
  - Write
  - Edit
  - Bash
  - Glob
  - Grep
  - Agent
  - AskUserQuestion
session-mode: run
contract:
  discovery: self-described
  consumes: []
  produces: []

<required_reading> @~/.maestro/workflows/run-mode.md </required_reading>

<purpose> Create or sync a session-level git worktree for parallel development. Supports `--sync` mode to pull latest main changes into an active worktree. </purpose>

<deferred_reading>

• [worktrees.json](~/.maestro/templates/worktrees.json) — read when updating registry
• [worktree-scope.json](~/.maestro/templates/worktree-scope.json) — read when writing scope marker

</deferred_reading>

<context> $ARGUMENTS -- session ID (or slug) and optional flags.

Terminology: this command uses 'session' throughout. The underlying workflow file (fork.md) may use 'milestone' as a legacy alias for 'session'. Treat them as equivalent: `--session` maps to workflow's `-m`, `state.json.sessions[]` maps to `state.json.milestones[]`.

`--base <ref>`: git ref (branch, tag, or commit hash) to fork from. Default: HEAD.

Modes (`Fork` / `Sync`), flags (`--session`, `--base`, `--sync`), session resolution, worktree layout, and artifact scoping are defined in workflow `fork.md`. </context>

<execution> Follow '~/.maestro/workflows/fork.md' completely.

Fork and sync algorithm steps are defined in workflow `fork.md`.

Gates (MANDATORY, BLOCKING)

**Fork mode:**

**GATE 1: Validation → Worktree Creation**

• REQUIRED: Session resolved from `state.json.sessions[]` by session_id or intent slug.
• REQUIRED: No existing active worktree for this session (E008).
• REQUIRED: Not running inside a worktree (E003).
• BLOCKED if: session not found (E006), already forked (E008), or running inside worktree (E003).

**GATE 2: Worktree Creation → Artifact Copy**

• REQUIRED: Git worktree created with branch (`session/{slug}`).
• REQUIRED: Shared `.workflow/` files copied (project.md, config.json, specs/).
• BLOCKED if missing: worktree creation failed or shared files not copied — do not proceed to artifact scoping.

**GATE 3: Artifact Copy → Completion**

• REQUIRED: [@ask] AskUserQuestion confirmation before registry writes — show session scope, worktree path, and state entries to be written. User must confirm or abort.
• REQUIRED: `worktree-scope.json` written with session scope (after confirmation).
• REQUIRED: Scoped `state.json` written (only this session's data) (after confirmation).
• REQUIRED: `worktrees.json` registry updated in main worktree (after confirmation).
• BLOCKED if missing: scope marker, scoped state, or registry update absent — worktree is unusable without these.

**Sync mode:**

**GATE: Sync → Completion**

• REQUIRED: Git merge main into worktree branch completed.
• REQUIRED: Shared artifacts re-copied.
• BLOCKED if: merge has unresolved conflicts or shared artifacts failed to copy.

</execution>

<completion>

Next-step routing

| Condition | Suggestion | |-----------|-----------| | Fork complete | `cd {wt.path}` then step `analyze` (`maestro run prepare analyze` + `maestro run create analyze --session YYYYMMDD-analyze-{topic} --intent "{goal}" --arg "{goal}"`) | | Fork + automated | `maestro delegate "run full lifecycle for session" --cd {wt.path} --mode write` | | Sync complete | Resume work in worktree | | Sync conflicts found | Resolve manually, then retry | </completion>

<error_codes> | Code | Severity | Condition | Recovery | |------|----------|-----------|----------| | E001 | error | Project not initialized | Run maestro-init first | | E002 | error | No roadmap found | Run step `roadmap` first (`maestro run prepare roadmap` + `maestro run create roadmap --session YYYYMMDD-roadmap-{topic} --intent "{goal}" --arg "{goal}"`) | | E003 | error | Running inside a worktree | Run from main worktree | | E004 | error | No session ID provided | Provide `--session <session_id>` | | E005 | error | No sessions defined in state.json | Run step `roadmap` first (`maestro run prepare roadmap` + `maestro run create roadmap --session YYYYMMDD-roadmap-{topic} --intent "{goal}" --arg "{goal}"`) | | E006 | error | Session not found in state.json.sessions[] | Check available sessions | | E007 | error | No active worktree for session (--sync) | Check worktrees.json | | E008 | error | Session already has active worktree | Merge or cleanup first | </error_codes>

<success_criteria> Fork mode:

• [ ] Session resolved from state.json.sessions[]
• [ ] Git worktree created with branch (`session/{slug}`)
• [ ] Shared `.workflow/` files copied (project.md, config.json, specs/)
• [ ] Session artifacts copied (matched by session/milestone name from workflow)
• [ ] `worktree-scope.json` written with session scope
• [ ] Scoped `state.json` written (only this session's data)
• [ ] `worktrees.json` registry updated in main worktree
• [ ] Session lifecycle recorded in worktrees.json registry (fork_sessions entry)
• [ ] Summary displayed with next-step commands

Sync mode:

• [ ] Git merge main into worktree branch
• [ ] Shared artifacts re-copied (project.md, config.json, specs/)
• [ ] Conflicts reported if any

</success_criteria>