breakdown-plan-into-tasks

name	breakdown-plan-into-tasks
description	Break down a large implementation plan into small, parallelizable tasks for individual developers. Use when user requests to break down a plan into tasks.

Task Breakdown Skill

Read the provided plan file thoroughly. Then follow the two-phase process below.

Phase 1: Codebase Analysis

Before breaking down any tasks, analyze the codebase to build accurate understanding and fill knowledge gaps the plan may leave implicit. This step prevents tasks that reference nonexistent files, wrong abstractions, or outdated patterns.

Specifically:

• Verify every file path and module the plan mentions — confirm they exist, or note that they need to be created
• Map current architecture — understand the existing patterns, conventions, and interfaces the plan builds on top of
• Identify hidden coupling — shared types, utilities, or config that the plan doesn't explicitly call out but that tasks will touch
• Check for prior art — search for existing implementations that partially cover what the plan describes (partial refactor, abandoned branch, utility function already written)

Use up to 3 parallel subagents (via the Agent tool) to speed up this phase and keep the main context window clean. Example split:

Subagent	Responsibility
Subagent 1	Verify file/module existence, map directory structure, check build/config files
Subagent 2	Trace data flow and interfaces the plan references — read relevant source files
Subagent 3	Search for prior art, existing utilities, and hidden coupling across the codebase

Each subagent should return a concise summary of findings. Use those summaries — not raw exploration — to inform the breakdown.

Phase 2: Task Breakdown

Using the plan plus the codebase analysis, break the work down into small, self-contained tasks that individual developers can pick up independently.

You may continue using up to 3 parallel subagents during this phase to draft batches of tasks concurrently. For example:

Subagent	Responsibility
Subagent 1	Draft Batch 1 tasks (no dependencies)
Subagent 2	Draft Batch 2 tasks (depends on Batch 1)
Subagent 3	Draft Batch 3+ tasks and the visual dependency diagram

Merge the subagent outputs into the final document, resolving any conflicts or gaps.

Output

Write the results in a new file alongside the plan, named {plan-filename}-tasks.md.

Task Format

Each task must include:

• Title — concise, action-oriented (e.g., "Extract WebSocket manager into ES module")
• Description — detailed enough for a developer unfamiliar with the plan to execute. Include source references (file paths, line numbers, function names, codeblocks), what to create/modify, and relevant context
• Acceptance Criteria — specific, verifiable checklist items
• Subtasks — only if the task is complex enough to warrant them
• Dependencies — exact task numbers this depends on, or "None"

Parallelization Strategy

Include a batch-based execution model at the top of the document:

1. Organize tasks into batches based on dependency order — all tasks within a batch can run in parallel with zero merge conflicts
2. Include a visual batch diagram showing the dependency flow
3. State merge order rules — which batches must merge before others can start
4. Provide a summary table — columns: #, Batch, Target File, Dependencies, Can Parallel With
5. Suggest developer assignment tracks — 2–3 developer assignment paths through the batches

Key Principles

• One task = only a few files (tightly coupled set) — minimize merge conflict surface
• Dependencies are explicit — every dependency listed by task number