| name | design |
| disable-model-invocation | true |
| description | Feature design methodology. Covers research, comparison, requirements
refinement, ideation, implementation planning, and DX completeness.
Use when starting a new feature, planning a refactor, or designing APIs.
Invoked via /design [topic].
|
| argument-hint | [feature or topic] |
Design
Structured approach to feature design. Not every step applies to every feature.
Skip steps that don't add value. The sequence matters more than completeness.
Steps
1. Research
What exists? Read the codebase. Read competing implementations. Read the docs.
Capture findings in DATA_SOURCES.md.
2. Compare
How do others solve this? Build a comparison matrix: feature vs platform.
Look for patterns across 3+ implementations.
3. Refine
Convert vague requirements ("make it fast") into measurable attributes
("p99 latency under 200ms"). Challenge ambiguous terms.
4. Ideate
Generate concrete features with examples. Each feature gets: name, one-line
description, CLI example or API shape, which attribute it serves.
5. Scope
Cut aggressively. What's the smallest thing that delivers the core value?
Use the Level Framework: Level 0 (platform), Level 1 (workflow), Level 2 (polish).
Build Level 0 first.
6. Plan
Vertical slices, not horizontal layers. Each slice is deployable and testable.
Count lines of code per slice. If a slice exceeds 500 lines, split it.
7. Critique
Run /critique on the plan before implementing.
8. DX Check
Every developer-facing feature needs three things:
- Tools — CLI commands, SDK methods, APIs
- Documentation — how to use it, with examples
- Agent support — can an LLM agent use it effectively?
If any leg is missing, the feature is incomplete.
Signs You Need to Double Back
- The plan has more than 10 slices
- You're building Level 2 before Level 0 exists
- The critique found more than 5 problems
- You can't demo the core value in under 2 minutes
- The scope grew since you started