context7

Context7 - Fresh Documentation

Objective: Eliminate hallucinations by injecting real-time, version-specific documentation into the context.

How to Use

1. Trigger: /context7 [query] or use context7
2. Process:
   • The agent searches for the library.
   • The agent fetches relevant docs for your query.
   • The agent generates code/answers based on that documentation.

Requirements

• MCP Server: Context7 MCP server must be configured in your Claude Code settings
• API Key: Configure via MCP server settings (set in Claude Code MCP configuration)
• No environment variables needed - MCP handles authentication

Workflow Example

User: "How do I do auth in Supabase? use context7"

Agent:

1. Call resolve-library-id with libraryName: "Supabase", query: "authentication" -> Returns /supabase/supabase-js
2. Call query-docs with libraryId: "/supabase/supabase-js", query: "how to authenticate users with examples"
3. Result: Returns official Supabase Auth documentation with code examples.
4. Answer: Generates code using the verified supabase.auth.signInWithPassword() method.

Best Practices

1. Be Specific: Use natural language questions, not keywords

   • Good: "How to implement middleware in Next.js App Router"
   • Bad: "nextjs middleware"

2. Pin Versions: When discussing a specific version, include it

   • Format: /org/library/v1.2.3
   • Example: /vercel/next.js/v15.1.8

3. Check Cache: Don't re-fetch if recent docs are in context

   • Context7 docs update infrequently
   • Caching for hours/days is appropriate

4. Mode Selection: Choose based on what you need

   Situation	Mode	Example Query
   Need explanation / learning	full	"how does Next.js middleware work"
   Debugging subtle behavior	full	"why is my middleware not being called"
   Unfamiliar library first contact	full	"how to use LangChain prompts"
   Need syntax / API signature	code_only	"Next.js middleware function signature"
   Implementing familiar pattern	code_only	"add JWT validation to Express middleware"
   Quick reference check	code_only	"React useCallback dependency array"

   Default to code_only unless: the query asks "how does X work", involves debugging, or targets a library not yet seen in the session.

   Note: The MCP tool output is markdown with code blocks. Post-filter by keeping only ``` blocks for token-efficient code-only mode.