Cortex Generates Typed SDKs, Interactive Docs and an MCP Server From One Spec File, MIT Licensed, Against Fern and ReadMe

GitHub (metrics via the GitHub API) and the Product Hunt leaderboard for 2026-09-12·medium signalXBlueskyLinkedInCopy link

Cortex took Product Hunt's #1 slot on September 12 with 151 votes for "turn API specs into docs, SDKs, and MCP servers," and the cortex-docs/cortex repo is MIT with 64 stars, last pushed that morning. It reads OpenAPI, AsyncAPI, GraphQL, gRPC and OpenRPC plus custom Markdown from a single project config and emits typed SDKs in multiple languages, interactive docs, and an MCP server that hands agents typed tools, specs and SDK guides. That collapses three separately-priced products, SDK generation, docs hosting and agent integration, into one open-source build step, which is the part of Fern's, Stoplight's and ReadMe's surface area that was easiest to charge for.