feature-plannerlisted

# Feature Planner The **first step** in the new-feature pipeline. Turns a vague request into a clarified requirement, a thought-through design, and an ordered list of vertical slices small enough to implement test-first. Hands off to [grill-with-docs](../grill-with-docs/SKILL.md) for stress-testing the plan, then to [tdd](../tdd/SKILL.md) for implementation. ## 1. When to invoke - User says "I want to build X", "let's add a feature for Y", "I'm starting on Z". - A request is vague enough that the right *shape* of the work isn't obvious. - A task is large enough that "just start coding" would lead to mid-flight rework. - The user explicitly asks for a plan, breakdown, or task list. If the work fits in one commit and the shape is obvious, **skip planning** and go straight to TDD. Plans pay back when the work is non-trivial. ## 2. The flow ``` Request → Requirement → Constraints → Design outline → Vertical-slice tasks ↓ ↓ ↓ ↓ ↓ "build X" what + why what's fixed shape + risks ordered, testable ``` Each step is a checkpoint with the user. Don't proceed to the next until the current one is confirmed. ## 3. Requirement clarification Distill the request into a one-paragraph description of *what* must be true after the work ships, and *why* it's worth shipping. Two paragraphs at most. Questions to ask before writing the requirement: - **Who is the user?** A human? Another service? A scheduled job? - **What outcom