API Checks Skill
Use this skill when you add or change route handlers in the Next.js App Router.
What this skill does
- Enforces a repeatable API review checklist
- Suggests improvements for validation, error handling, and response shapes
- Flags common pitfalls that cause 500s or inconsistent behavior
Checklist
- Confirm the handler covers the expected HTTP methods.
- Validate inputs early and return 400 for client errors.
- Normalize error responses with consistent structure.
- Set explicit status codes for success and errors.
- Avoid leaking internal error details in responses.
- Ensure JSON responses are serialized correctly.
Example
When reviewing a route handler, apply the checklist and propose edits.
Input:
"Add POST /api/notes that stores a note and returns it"
Output:
"- Add input validation (title required, content max length)
- Return 201 with JSON body
- Catch errors and return 500 with a safe message"
