Cursor rule

1---
2description: "Fetch current library docs via Context7 MCP instead of training data. Use when user asks about frameworks, APIs, setup, or code examples for React, Next.js, Prisma, etc."
3alwaysApply: false
4---
5 
6# Context7 MCP
7 
8> **HARD GATE** — Max **3** Context7 tool calls per user question (`resolve-library-id` + `query-docs` count toward the cap). On quota/rate-limit errors, emit an explicit **CONTEXT7_UNAVAILABLE** block — do NOT silently answer from training data.
9>
10> **HARD GATE** — Before HTTP fetch, check `bash scripts/lib/doc-fetch-cache.sh get "<libraryId>:<query>"`. Cache hit within TTL → use cached body (no round-trip). On ETag mismatch after conditional refresh, replace cache entry.
11 
12## When to Use
13 
14- Setup/configuration questions ("How do I configure Next.js middleware?")
15- Code involving libraries ("Write a Prisma query for…")
16- API references ("What are the Supabase auth methods?")
17- User mentions specific frameworks (React, Vue, Svelte, Express, Tailwind, etc.)
18 
19## Bounded Retry (max 3x)
20 
21| Attempt | Action |
22|---------|--------|
23| 1 | `resolve-library-id` → pick best match |
24| 2 | `query-docs` with selected `libraryId` |
25| 3 | Retry `query-docs` once with refined query (narrower scope) |
26 
27After 3 failures, stop and print:
28 
29```
30CONTEXT7_UNAVAILABLE
31Reason: <quota|rate-limit|no-match|timeout>
32Action: Ask user to retry later, paste official docs URL, or run `bts docs <lib>`.
33Do NOT substitute training-data answers without labeling them UNVERIFIED.
34```
35 
36## Fetch Cache (ETag-revalidated)
37 
381. **Cache key:** `"<libraryId>:<normalized-query>"` (lowercase, trimmed).
392. **Read:** `bash scripts/lib/doc-fetch-cache.sh get "<key>"` — exit 0 → use cached body.
403. **Miss / stale:** call `query-docs`; store via `doc-fetch-cache.sh put`.
414. **TTL:** 300s default (`DOC_CACHE_TTL`). Stale entries refresh on next fetch; honor `ETag` when MCP returns it.
42 
43`bts docs <lib>` shares the same cache helper when invoked from this skill.
44 
45## Process
46 
471. `resolve-library-id` with `libraryName` + full user `query`.
482. Select match: name similarity, reputation, benchmark score; prefer version-specific IDs when user names a version.
493. `query-docs` with `libraryId` + specific question (one concept per call).
504. Answer using fetched docs; cite library/version when relevant.
51 
52## Verify
53 
54→ verify: `test -f scripts/lib/doc-fetch-cache.sh`
55