context7: current library docs inside Claude

Libraries change faster than a model’s training data. context7 gives Claude a way to fetch the current docs for a library before answering, so config options and APIs match the version you actually have.

What’s inside: MCP server. Published by: Anthropic, in the official marketplace.

How it works

The plugin adds an MCP server with two tools:

  • resolve-library-id turns a name like "vite" into a Context7 library id
  • query-docs fetches the sections of that library’s docs relevant to your question

The server’s instructions tell Claude to use it whenever you ask about a library, framework, SDK or CLI. Only the matching snippets enter the conversation.

Install

/plugin marketplace add anthropics/claude-plugins-official
/plugin install context7@claude-plugins-official
claude plugin marketplace add anthropics/claude-plugins-official
claude plugin install context7@claude-plugins-official

Skip the first line if you already added the claude-plugins-official marketplace. Reload the VS Code window or restart claude afterwards. New to plugins? See the install guide in this series.

How to use it

Ask library questions normally. Add "use context7" to make sure it looks things up rather than answering from memory.

  • How do I configure a web worker in Vite? use context7
  • What changed in React Router’s lazy routes in the latest version?
  • Show me the Tailwind 4 syntax for a custom variant

Good use cases

  • Configuration questions for build tools
  • Upgrading to a new major version of a dependency
  • Newer libraries the model barely knows

When not to use it

Questions about your own code, general programming concepts, or debugging business logic. There are no library docs to look up there.

How we use it on Zykit