Rust Docs MCP server

This is a small helper program that gives your AI assistant fresh, accurate documentation for one Rust crate at a time. It is handy if you write Rust code with an AI assistant and keep getting suggestions that use old or wrong versions of a library. You run one copy of it per crate you care about.

What this MCP server does

You start the server and tell it which Rust crate you want, for example serde or tokio. The first time, it downloads that crate's documentation and turns it into a searchable form, which can take a few minutes. After that, when you ask your AI a question about the crate, the AI sends the question to this helper. The helper finds the most relevant part of the docs and asks an AI model to write a short answer based only on that part. You get the answer back in your chat, prefixed with the crate name.

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What you can do with it

• Ask how to use a specific function or type in a Rust crate
• Get answers based on the current documentation, not old training data
• Run several copies at once, one for each crate you use
• Specify a crate version, like reqwest@0.12.0, to match your project
• Turn on crate features so the docs match your setup
• Reuse cached docs on later runs so startup is fast

Try asking your AI

• “How do I make a simple GET request with reqwest?”
• “What is the difference between Serialize and Deserialize in serde?”
• “Show me how to spawn a task with tokio and wait for it.”
• “What does the ClientBuilder timeout method do in reqwest?”

What it gives back to you

You get a short written answer in your chat, based on the crate's documentation. It starts with a label like From serde docs: so you know where it came from. The answer is plain text, not code files or lists of links. If the docs do not cover your question, the answer may be vague or say it cannot find it.

Before you start

Who it's for

Rust developers who use an AI coding assistant and want it to suggest code that matches the current version of a crate.