Name: Cortex
Rating: 5.0 (1 reviews)

Cortex is an open source API knowledge layer that turns OpenAPI, AsyncAPI, GraphQL, gRPC, and OpenRPC specs into interactive documentation, typed SDKs in 11 languages, and MCP servers for AI agents.

What I liked most is that Cortex keeps API docs, SDKs, and MCP tools in the same workflow instead of treating them as separate projects. I changed the API spec a few times and could regenerate everything from the same config, which made the whole process feel much simpler.

The TypeScript output worked well in my tests, and having a usable MCP server generated alongside the SDKs was especially convenient. It feels useful for teams that want to keep several developer-facing outputs in sync without maintaining each one by hand.

A few things still felt a bit rough around the edges. MCP auth was the main one for me — I expected the bearer auth from my OpenAPI spec to carry over, but it didn’t, so internal APIs need a bit of extra setup.

I also hit a couple of Python packaging issues, and a simple cortex generate --check for CI would be really handy.

Nothing major, but fixing these would make the workflow feel a lot smoother for real projects.

I didn’t do a direct comparison with tools like Fern, Stainless, or OpenAPI Generator. My usual setup would be to use separate tools for SDK generation and documentation, then build the MCP layer separately.

What made Cortex interesting to me was having those pieces connected through one config and one generation workflow, rather than managing each output on its own.

Cortex

Turn API specs into docs, SDKs, and MCP servers

Turn API specs into docs, SDKs, and MCP servers

Cortex Reviews

The community submitted 1 review to tell us what they like about Cortex, what Cortex can do better, and more.

What's great

What needs improvement

vs Alternatives