TIPThis project is open-sourced at Tokisaki-Galaxy/zig-docs-mcp. Feel free to give it a star.
TIPProvide public mcp servers, but encourage self-host to reduce the pressure on servers https://zigdocs.api.tski.uk/mcp.
Why I built Zig Docs MCP
The official Zig documentation is excellent. But it is still mainly a set of web pages. In real development, I usually do not want to read a whole page. I want the signature, the parameters, the error set, or the short explanation for one symbol.
And zig has not yet released a stable version, and it is still rapidly iterating in the 0.x version. Vibe coding is not very friendly to this rapidly changing document support, and often uses the old version of the document memorized during training, which often leads to outdated or inaccurate answers. If agent directly queries the samples/documents of local zig installation, it will consume a lot of token and contexts. A better method is docs MCP service, which directly allows AI assistants to directly query the latest version of documents.
I built Zig Docs MCP to turn that information into a set of tools that can be called directly. In this way, AI assistants, editor plugins, and scripts can query Zig docs as naturally as they query an API.
What problem it solves
Daily Zig work often involves very small tasks.
- Looking up a builtin definition
- Searching for types and functions in the standard library
- Browsing documentation by version
- Letting AI fetch structured context directly
If every lookup requires switching between web pages, the workflow becomes slow. Zig Docs MCP breaks the documentation into interfaces that are searchable, callable, and reusable.
The main tools are:
list_builtin_functions: list builtin functionsget_builtin_function: query a builtin’s signature and descriptionsearch_std_lib: search standard library symbolsget_std_lib_item: retrieve the full documentation for one item
The point is not only that you can search. It is that the documentation becomes a programmable resource. That is useful for IDE integration, autocomplete, and AI-assisted Q&A.
How it is implemented
The project is roughly split into two layers.
1. TypeScript / Bun layer
The mcp/ directory handles the MCP server entrypoint, document caching, version indexes, local previews, and R2 bundle generation.
This layer acts more like an orchestration center. It organizes the data produced by the Zig side into stable interfaces.
2. Zig / WASM layer
The docs/ directory handles the actual document parsing and AST traversal.
It scans standard library declarations, parses functions, types, fields, and error sets, then generates structured Markdown and search indexes. The final output is compiled into WASM for the TypeScript side to consume.
The benefit is simple: Zig understands Zig’s syntax and AST, while the frontend and Worker side only need to consume the results.
What I value most
What matters most to me is not just whether the docs can be searched, but whether the result can flow directly into the workflow.
Shorter lookup paths.
I used to jump between web pages, source code, and versioned docs. Now it feels closer to asking a tool for the answer directly.
Versioning is more practical.
Many projects do not use the latest Zig. They stay on a fixed version. This project supports versioned packaging and caching, which fits real-world development better.
Better for AI integration.
That is where MCP shines. The client can fetch structured results directly, without manually copying documentation into prompts.
One detail I like a lot
This project is not just a static documentation mirror. It is closer to documentation productization.
When querying std.hash_map.HashMap, you can directly get:
- what kind of type it is
- how to initialize it
- its common methods
- links to docs, errors, and source entry points
That feels much closer to a knowledge interface than a plain HTML page.
Who it is for
- Developers who write Zig
- People who want Zig docs inside AI tools
- People who want an MCP service example
- Anyone who needs versioned docs and local caching
Closing
If traditional documentation is written for humans, Zig Docs MCP is closer to being written for both humans and tools.
It turns Zig documentation from web pages into a service that can be searched, integrated, and automated. To me, that is the most practical side of MCP: knowledge does not stay on the page. It enters the workflow.