Cortex
Cortex - Generates interactive API documentation, typed SDKs, and MCP servers from OpenAPI, AsyncAPI, GraphQL, gRPC, OpenRPC, and Markdown.
Cortex is an open-source API client project on GitHub under the MIT license (permissive), with 3.3k stars. It is built with TypeScript and Express. Its last push was 28 days ago.
- Stars
- 3.3k
- License
- MIT
- Activity
- Active
- Latest release
- v0.1.36
Judgement
- What it is
- Developer tool
- What it does
- A generator that turns OpenAPI, AsyncAPI, GraphQL, gRPC, OpenRPC and Markdown into interactive API docs, typed SDKs and an MCP server from one configuration.
- Adopt it when
- You maintain a public API and want docs, SDKs and an MCP server generated together.
- Watch out
- Still at version 0.1.x despite the old repository, so expect changes.
- Ready for
- Usable
- Runs as
- Command line
- Built with
- TypeScript and Express
- How established
- Established: started 11 years ago, latest release v0.1.36.
- What the license allows
- You can build it into a product you sell, as long as you keep its copyright notice.
Judged on 2026-11-03 from the project's README and GitHub data. The license and age lines are worked out directly.
Built from
Follow it down: Cortex → TypeScript → Go → runs on a microchip
Open-source alternatives to Cortex
-
1
Hoppscotch hoppscotch
Open-Source API Development Ecosystem • https://hoppscotch.io • Offline, On-Prem & Cloud • Web, Desktop & CLI • Open-Source Alternative to Postman, Insomnia
Developer tool Production-ready Your team wants a Postman-like client that it can self-host or use in the browser.
★ 81k MIT TypeScript Active, pushed 2 days ago -
2
Bruno usebruno
Opensource IDE For Exploring and Testing API's (lightweight alternative to Postman/Insomnia)
Developer tool Production-ready You want Postman-style testing without cloud sync, keeping collections in your repository.
★ 48k MIT JavaScript Active, pushed today -
3
Insomnia Kong
The open-source, cross-platform API client for GraphQL, REST, WebSockets, SSE and gRPC. With Cloud, Local and Git storage.
Developer tool Production-ready You need an API client with API design features and work in the Kong ecosystem.
★ 40k Apache-2.0 TypeScript Active, pushed today -
4
Yaak mountain-loop
The most intuitive desktop API client. Organize and execute REST, GraphQL, WebSockets, Server Sent Events, and gRPC 🦬
Developer tool Production-ready You want a fast, local Postman alternative without an account.
★ 19k MIT TypeScript Active, pushed yesterday -
5
Scalar scalar
Scalar is an open-source API platform: 🌐 Modern REST API Client 📖 Beautiful API References ✨ 1st-Class OpenAPI/Swagger Support
Developer tool Production-ready You publish an OpenAPI spec and want better-looking docs than Swagger UI with try-it-out requests.
★ 16k MIT TypeScript Active, pushed today -
6
RWKV-Runner josStorer
A RWKV management and startup tool, full automation, only 8MB. And provides an interface compatible with the OpenAI API. RWKV is a large language model that is fully open source and available for commercial use.
Complete system Usable You want to run RWKV models on your own PC and use them from ChatGPT-style clients.
★ 6.5k MIT TypeScript Active, pushed today -
7
Notion-sdk-js makenotion
Official Notion JavaScript Client
Building block Production-ready You build an integration or automation against Notion in JavaScript.
★ 5.7k MIT TypeScript Active, pushed today -
8
Hey API hey-api
👨🚀 Turn API specifications into production-ready SDKs, validators, mocks, and more. 20+ plugins. Millions of weekly npm downloads. Used by Vercel, OpenCode, PayPal, AWS, Autodesk, and many more.
Developer tool Production-ready Your TypeScript front end or service consumes an OpenAPI-described API and you want generated, typed clients.
★ 5.6k MIT TypeScript Active, pushed 2 days ago
Commercial API clients and testing tools
-
1
Postman Postman, Inc.
Go faster from development to production with higher accuracy and fewer tokens.
Developer tool Production-ready A team wants shared API collections, tests and documentation in one widely known tool.
1k readers a month Commercial
Stars, license and activity come from GitHub and refresh on a rolling hourly schedule. The project's own description is quoted as written.