wf3-plan_skill

Overview

This skill creates or updates an implementation Plan document that divides a spec into discrete, testable development steps. It validates prerequisites, analyzes the spec and codebase, and generates a step-by-step execution plan with risk assessments and dependencies. The output is a committed plan file and updated workflow state ready for review or implementation.

How this skill works

The skill checks prerequisites (active work and presence of 02_SPEC.md), loads the spec, and extracts affected components, detailed changes, and a test strategy. It inspects the codebase to identify target files, dependency order, and risks, then divides the work into 5–10 committable steps (each mapped to one /wf5-implement run). It fills the PLAN template, updates state.json with plan metadata, commits the plan, and presents a completion summary.

When to use it

• Starting implementation after a specification (02_SPEC.md) is finalized
• Splitting a large change into independent, testable units
• Preparing handoff for parallel work or code review
• When you need an explicit dependency and risk breakdown before coding
• Before running /wf5-implement to ensure safe, ordered execution

Best practices

• Keep each step small and committable: ~50–200 lines, 1–5 files, single logical change
• Place foundation and interface changes before dependent work
• Include tests with the implementation or immediately after in the same step
• Respect strict dependency order; do not introduce out-of-scope changes
• Document completion criteria and estimated effort for every step

Example use cases

• Create a plan for adding a new feature that touches backend, API, and tests
• Break a refactor into safe, reversible steps with clear rollback points
• Prepare parallelizable tasks for multiple contributors while listing dependencies
• Update an existing plan when the spec or codebase changes
• Generate a step detail view (step <n>) to communicate tasks to an implementer