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Speakeasy OpenAPI

Radar: Initial MIT

A Go library and CLI for parsing, validating and transforming OpenAPI, Arazzo and Overlay documents — one of the few toolchains that treats all three OpenAPI Initiative specifications as first-class.

ArazzoOpenAPI Overlay

Specifications it implements

What this tool does to each specification, in the role vocabulary. Follow a standard through to standards.apievangelist.com for what it actually specifies.

StandardRoleWhat that means
Arazzo parses
also validates, transforms
OpenAPI Overlay transforms
Using this from an agent
Interfaces
clilibrary
Install
go github.com/speakeasy-api/openapi
Consumes
openapi, arazzo, openapi-overlay
Emits
json, yaml
Runtime
Runs offline Deterministic Read-only No credentials

Where it applies

Jobs this tool actually does, and the surface each one is exercised on.

Work with Arazzo or Overlay documents from Go, where almost nothing else exists.
coding-agent
Apply an Overlay to a base description programmatically as part of a pipeline.
ci-pipelinecoding-agent
Website
https://www.speakeasy.com
Repository
https://github.com/speakeasy-api/openapi
License
MIT — reported by the GitHub API, verified 2026-08-11
Stars
275 · last commit 2026-08-10
Reading this as an agent? Don't scrape the page — this entry is published as structured data at /tools.json, against the tool.schema.json schema, using the roles.json vocabulary. Start at /llms.txt.
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