| name | extension-spec |
| description | Designs pi extensions — new or refactoring — with full PRD, TypeScript best practices, anti-pattern audit, and migration plan. Use when creating, updating, or refactoring a pi extension. |
Extension Spec Skill
Design pi extensions following pi docs, TypeScript best practices, and anti-pattern audit.
Setup
No setup needed. All reference docs included.
How It Works
- Load full spec:
read references/extension-spec.md
- Follow phases — ANALYZE SCOPE → RESEARCH → ARCHITECTURE → PRD → DELIVERY
- Check pi docs:
read /usr/lib/node_modules/@earendil-works/pi-coding-agent/docs/extensions.md
- Check examples:
ls /usr/lib/node_modules/@earendil-works/pi-coding-agent/examples/extensions/
- List existing extensions:
ls .pi/extensions/*.ts .pi/extensions/*/index.ts 2>/dev/null
Mode Detection
See references/extension-spec.md Mode Detection table.
| Input | Mode | Action |
|---|
refactor:<name> / update:<name> / fix:<name> | Refactor | Read existing extension, audit, produce PRD + migration |
$@ file in .pi/extensions/ | Refactor | Same — read, audit, produce PRD |
| Other / no arg | New | Analyze, research, design from scratch |
Rules
- Designer not coder — PRD first, code second
- Research before propose — pi docs, existing extensions, best practices
- PRD standalone — not a diff, not snippets
- No
any types, no details: {}, no module-level mutable state
- Files < 300 lines, entry < 100 lines
- Use
pi.exec(), ctx.sessionManager, ctx.ui.*, pi.sendUserMessage(), ctx.cwd
- Refactor: read existing first, preserve external contracts
Output
- Write PRD to
.pi/specs/<name>-prd.md
- Offer to implement or create GitHub issue
- If
$@ --implement: code after PRD
Reference
See full spec for:
- Complete PRD template
- Anti-pattern checklist (C1-C14, M1-M8, R1-R6, P1-P24)
- Phase details (0-4)
- Security considerations
- Priority matrix (P0-P3)
