Library Documentation Skill
Fetches official library documentation with 60-90% token savings.
WHEN TO INVOKE (Auto-Detection)
INVOKE AUTOMATICALLY when:
| Context | Detection Signal | Content Type |
|---|---|---|
| Implementing | About to write code using library API | examples,api-ref |
| Debugging | Error contains library name (e.g., PrismaClientError) | troubleshooting |
| Installing | Adding new package, npm install, setup task | setup |
| Integrating | Connecting libraries ("use X with Y") | examples,setup |
| Upgrading | Version migration, breaking changes | migration |
| Uncertain | First use of library feature, unsure of pattern | examples |
DO NOT INVOKE when:
- Already have sufficient knowledge from training
- User pasted docs or has them open
- Task is about local/private code (use codebase search)
- Comparing libraries (use web search)
DECISION LOGIC
1. Identify Library
Priority: User mention → Error message → File imports → package.json → Ask userExamples:
PrismaClientKnownRequestError→ library = "prisma"import {useState} from 'react'→ library = "react"from fastapi import FastAPI→ library = "fastapi"
2. Identify Topic
Priority: User specifies → Error message → Feature being implemented → "getting started"3. Select Content Type
| Task | Content Type |
|---|---|
| Implementing code | examples,api-ref |
| Debugging error | troubleshooting,examples |
| Installing/setup | setup |
| Integrating libs | examples,setup |
| Upgrading version | migration |
| Understanding why | concepts |
| Best practices | patterns |
EXECUTION
IMPORTANT: Always use the Python entry point (fetch-docs.py) for cross-platform compatibility.
Use python3 on Linux/macOS/WSL, python on Windows:
# With known library ID (faster - saves 1 API call)
python3 scripts/fetch-docs.py --library-id <id> --topic "<topic>" --content-type <types>
# With library name (auto-resolves)
python3 scripts/fetch-docs.py --library <name> --topic "<topic>" --content-type <types>Windows note: Usepythoninstead ofpython3(e.g.,python scripts/fetch-docs.py...)
Quick Library IDs
| Library | ID |
|---|---|
| React | /reactjs/react.dev |
| Next.js | /vercel/next.js |
| Prisma | /prisma/docs |
| Tailwind | /tailwindlabs/tailwindcss.com |
| FastAPI | /tiangolo/fastapi |
See references/library-ids.md for complete list.
ERROR HANDLING (Quick Reference)
| Error | Action |
|---|---|
[LIBRARY_NOT_FOUND] | Try spelling variations |
[LIBRARY_MISMATCH] | Use --library-id directly |
[EMPTY_RESULTS] | Broaden topic or use --content-type all |
[RATE_LIMIT_ERROR] | Check API key setup |
Call Budget: Context7 allows 3 calls/question. Use --library-id to save 1 call.
See references/context7-tools.md for full error handling.
REFERENCES
- Library IDs - Complete library ID list
- Usage Patterns - Real-world examples
- Context7 Tools - API details, error codes, setup