/implement-swarm

description: "Implement from conversation context with parallel swarm"
argument-hint: "<task description> [--workers N] [--model MODEL]"
allowed-tools: ["TaskCreate", "TaskUpdate", "TaskList", "TaskGet", "Task", "Bash"]
model: opus

Implement Swarm Command

Execute implementation from conversation context using parallel workers. All workers complete → done.

**Note:** Loop and swarm are interchangeable - swarm is just faster when tasks can run in parallel. Both enforce exit criteria and sync state.

**Source:** Conversation context + argument input + mentioned files.

Uses Claude Code's built-in Task Management System for dependency tracking and visual progress (`ctrl+t`).

Arguments

• `<task description>` (required): What to implement
• `--workers N` (optional): Max concurrent workers (default: 3)
• `--model MODEL` (optional): Model for workers: haiku, sonnet, opus (default: sonnet)

Instructions

Step 1: Create Task Graph Immediately

**ONLY use what's already available:**

• The user's argument input
• Conversation history (already in context)

**DO NOT:**

• Read files unless the user explicitly asks you to
• Grep or explore the codebase
• Use Glob to find files

Create tasks immediately from context. Include file paths in task descriptions so workers can read them during execution.

For each work item, create a task:

TaskCreate({
  "subject": "Fix auth token validation",
  "description": "Full implementation details from context",
  "activeForm": "Fixing auth token validation"
})

**Set dependencies with `addBlockedBy`** — identify which tasks depend on others completing first:

// Task 2 needs the type fix from task 1
TaskUpdate({
  "taskId": "2",
  "addBlockedBy": ["1"]
})

A task with non-empty `blockedBy` shows as **blocked** in `ctrl+t`. When a blocking task is marked `completed`, it's automatically removed from the blocked list. A task becomes **ready** when its blockedBy list is empty.

Step 2: Spawn Workers

**Worker limit N** = `--workers` value or **3** if not specified. This is a queue — spawn up to N, then wait for completions before spawning more.

Mark each task `in_progress` before spawning its worker. Spawn up to N background workers in a **SINGLE message** (all Task calls in one response):

Task({
  "description": "Task-1: Fix auth validation",
  "subagent_type": "general-purpose",
  "model": "sonnet",
  "run_in_background": true,
  "allowed_tools": ["Read", "Edit", "Write", "Bash", "Glob", "Grep"],
  "prompt": "Execute this ONE task then exit:\n\nTask ID: 1\nSubject: Fix auth token validation\nDescription: <full details>\n\nSteps:\n1. Execute the task (read files, make changes, verify)\n2. Output ONLY a one-line summary\n3. Exit immediately"
})

After all Task() calls return, output a status message like "3 workers launched. Waiting for completions." and **end your turn**. The system wakes you when a worker finishes.

Step 3: Process Completions

When a worker finishes, you are automatically woken. Then:

1. **TaskUpdate** — mark the finished worker's task as `completed` 2. **TaskList()** — see overall progress and find newly unblocked tasks 3. **Find ready tasks**: A task is ready when its status is `pending` AND its `blockedBy` list is empty. Completing a task automatically removes it from other tasks' `blockedBy` lists, potentially unblocking them. 4. Mark ready tasks `in_progress` and spawn new workers if slots available (respect worker limit N) 5. Output status and **end your turn** — you will be woken on the next completion

**Task lifecycle**: `pending` → (blocked until deps complete) → `in_progress` → `completed`

Repeat until all tasks completed → say **"Swarm complete"**

Visual Progress

Press `ctrl+t` to see task progress:

Tasks (2 done, 2 in progress, 3 open)
■ #3 Fix validation (Worker-1)
■ #4 Update tests (Worker-2)
□ #5 Integration > blocked by #3, #4

Context Tips

• Reference specific messages from conversation
• Use patterns agreed upon in discussion
• If anything is unclear, ask before spawning

Error Handling

| Scenario | Action | |----------|--------| | Context unclear | Ask for clarification | | Worker fails mid-task | Other workers continue | | All tasks blocked | Circular dependency | | Context compacted | TaskList → spawn ready tasks → end turn |

Stopping

• Workers self-terminate when no work remains
• Use `/cancel-swarm` to halt early

Example Usage

# After discussing a bug
/implement-swarm fix the auth bug we discussed

# With worker override
/implement-swarm refactor the API handlers --workers 5

# Cheaper workers for simple tasks
/implement-swarm update all the error messages --model haiku