rustdoc-query

Make AI slightly less stupid about Rust APIs.

rustdoc-query queries crate public APIs from docs.rs rustdoc JSON. Use it as an embeddable Rust library or an MCP server.

Public surface

The supported Rust API is:

• rustdoc_query::contract::generated::* for versioned request and outcome types
• rustdoc_query::service::RustdocQueryService for crate queries
• rustdoc_query::mcp::RustdocMcpServer for an embeddable MCP adapter

Other modules are implementation details.

The service operates on public API only. It provides crate and module overviews, public item detail, name search, and documentation search. The generated v2 contract is the source of truth for request fields, defaults, and outcomes.

Output formats

JSON is the default representation. TOON is available for compact text output. The request and outcome types are unchanged.

Library users can call RustdocQueryService::json_value or RustdocQueryService::toon. MCP users can set RUSTDOC_QUERY_OUTPUT_FORMAT=toon or pass --output-format toon.

Library

Add the package as a dependency:

[dependencies]
rustdoc-query = "0.1"

Construct RustdocQueryService, then call its async overview, find, or get_item methods with the corresponding generated request type. Results are the matching generated outcome type and include typed API errors.

API documentation is available at docs.rs.

MCP server

Install from crates.io:

cargo install rustdoc-query

Or install a release build:

curl -LsSf https://releases.gnu.foo/rustdoc-query/latest/install.sh | sh

The server uses stdio JSON-RPC. A client configuration needs this command:

{
  "command": "rustdoc-query"
}

It registers these tools:

• crate_overview
• find_items, including documentation search
• get_item

Logs are written to standard error. Set RUSTDOC_QUERY_CACHE_DIR to override the local rustdoc cache directory.

Build from source

git clone https://github.com/gnufood/rustdoc-query.git
cd rustdoc-query
mise install --locked
just build
./target/debug/rustdoc-query

Development

just hooks-install

Command	Purpose
just build	Build the workspace.
just check	Type-check all workspace targets.
just test	Run the test suite with nextest.
just lint	Run Clippy.
just schema	Verify generated schema artifacts.
just ci	Run the full local CI sequence.

License

Licensed under either of:

• Apache License, Version 2.0
• MIT license

at your option.