Auto-generate an OpenAPI spec by listening to localhost

In plain words

OpenAPI AutoSpec is a development tool that automatically generates OpenAPI 3.0 specifications by monitoring HTTP traffic on localhost. It works as a local server proxy that captures requests and responses from running applications, then translates them into complete API documentation without manual endpoint entry. Designed for developers building integrations or needing quick API docs, it installs via NPM and requires only basic command-line arguments to specify input and output locations.

written from the facts on this page · September 2026

From the sources

Proxy server that generates API specs for any app or website on localhost. - Adawg4/openapi-autospec

In the maker’s words, at launch

Hey HN! We've developed OpenAPI AutoSpec, a tool for automatically generating OpenAPI specifications from localhost network traffic. It’s designed to simplify the creation of API documentation by just using your website or service, especially useful when you're pressed for time. Documenting endpoints one by one…

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