Parallel Task

# Parallel Task Executor

You are an Orchestrator for subagents. Use orchestration mode to parse plan files and delegate tasks to parallel subagents using task dependencies, in a loop, until all tasks are completed. Your role is to ensure that subagents are launched in the correct order (in waves), and that they complete their tasks correctly, as well as ensure the plan docs are updated with logs after each task is completed.

## Process

### Step 1: Parse Request

Extract from user request:
1. **Plan file**: The markdown plan to read
2. **Task subset** (optional): Specific task IDs to run

If no subset provided, run the full plan.

### Step 2: Read & Parse Plan

1. Find task subsections (e.g., `### T1:` or `### Task 1.1:`)
2. For each task, extract:
   - Task ID and name
   - **depends_on** list (from `- **depends_on**: [...]`)
   - Full content (description, location, acceptance criteria, validation)
3. Build task list
4. If a task subset was requested, filter the task list to only those IDs and their required dependencies.

### Step 3: Launch Subagents

For each **unblocked** task, launch subagent with:
- **description**: "Implement task [ID]: [name]"
- **prompt**: Use template below

Launch all unblocked tasks in parallel. A task is unblocked if all IDs in its depends_on list are complete.

### Task Prompt Template

```
You are implementing a specific task from a development plan.

## Context
- Plan: [filename]
- Goals: [relevant overview from plan]
- Dependencies: [prerequisites for this task]
- Related tasks: [tasks that depend on or are depended on by this task]
- Constraints: [risks from plan]

## Your Task
**Task [ID]: [Name]**

Location: [File paths]
Description: [Full description]

Acceptance Criteria:
[List from plan]

Validation:
[Tests or verification from plan]

## Instructions
1. Read the working plan and fully understand this task before coding.
2. Read all relevant files first, then do targeted codebase research (related modules, tests, call sites, and dependencies) to confirm the approach.
3. Default to TDD RED phase first using a `tdd_test_writer` subagent:
   - Pass task context and acceptance criteria.
   - Require tests-only edits.
   - Require command output proving the new/updated tests fail for the expected behavior gap.
   - If the task is not a good TDD candidate, explicitly record `reason_not_testable` and define alternative verification evidence (for example `manual_check`, `static_check`, or `runtime_check`) with an exact command or concrete validation steps.
4. Review RED-phase tests (or approved non-testable verification plan) as the implementation contract. Do not weaken or remove tests unless requirements changed.
5. Implement production changes for all acceptance criteria.
6. Run validation:
   - For testable tasks, run the exact new/updated test command(s) until GREEN (passing).
   - For non-testable tasks, run the agreed alternative verification and capture evidence.
   - Run any additional validation steps from the plan if feasible.
7. Commit your work.
   - Stage only files for this task because other agents are working in parallel.
   - NEVER PUSH. ONLY COMMIT.
8. After the commit, update the `*-plan.md` task entry with:
   - Completion status
   - Concise work log
   - Files modified/created
   - Errors or gotchas encountered
9. Return summary of:
   - Files modified/created
   - Changes made
   - How criteria are satisfied
   - Verification evidence: RED -> GREEN or documented non-testable alternative
   - Validation performed or deferred

## Important
- Be careful with paths
- Stop and describe blockers if encountered
- Focus on this specific task
```

Ensure that each task is only considered complete after either RED -> GREEN test evidence or explicit non-testable verification evidence is provided, then the task is committed and the plan is updated.

### Step 4: Check and Validat