Context7: Up-to-Date Library Docs for Claude

Context7, from Upstash, gives coding agents current, version-specific documentation for libraries and frameworks. Instead of relying on training data that may predate the latest release, Claude looks up the docs for the exact library it is working with.

Install

The quickest route is the setup CLI (requires Node.js 22.13 or newer):

npx ctx7 setup --claude

It signs you in with OAuth, creates an API key, and lets you choose CLI + Skills mode (a skill that tells Claude to call ctx7 commands, no MCP needed) or MCP mode. Remove it later with npx ctx7 remove.

To configure MCP manually, point Claude Code at the hosted server and pass your key as a header:

claude mcp add --transport http context7 https://mcp.context7.com/mcp \
  --header "Authorization: Bearer YOUR_API_KEY"

Context7 is also listed as a plugin in Anthropic’s official marketplace; see the plugins guide.

Use cases

Add “use context7” to a prompt, or set a rule so Claude uses it automatically:

How do I set up middleware in the latest Next.js? use context7
Write a Prisma migration for a many-to-many relation. use context7

• Avoiding deprecated APIs in fast-moving frameworks.
• Upgrades where the old and new versions differ.
• Learning an unfamiliar library without pasting docs into chat.

Pros

• Fixes the most common source of wrong code: outdated API knowledge.
• Two modes, so you can skip MCP entirely if you prefer skills.
• Free tier with an optional key for higher limits.

Cons

• Depends on a third-party hosted service and its coverage of your library.
• Retrieved docs add tokens to context.
• Rate limits apply without a key.

Building your own docs workflow instead? See Claude Code skills and the MCP guide.