Lockspec

Gives coding agents version-pinned API contract details from your OpenAPI specs, so generated calls match the real endpoints and types.

What you can do

Loads an OpenAPI 3.0 or 3.1 spec from a file, URL, or text, normalizes and indexes it, and pins it as a versioned snapshot. Tools let an agent find operations by intent or path, look up named schemas, read exact request and response signatures, and structurally validate a draft request against the pinned spec. It can also list loaded specs, switch the active version, remove a spec or version, and diff two versions as breaking or non-breaking.

When to use it

Useful when an agent writes code against an API whose spec is private, internal, third-party, too large for context, or not in the repository. Also helpful when several API versions are live at once and you want the agent pinned to a chosen version rather than the latest one it saw.

Requirements

Local process run through npx (npm package lockspec) or from a built source checkout; requires Node 22 or newer. No accounts, API keys, or environment variables are declared. Specs are fetched once and then served offline from ~/.lockspec/.