Notes

Number of APIs: 0

They don't have an API, that is easy to turn into anything.

Searched for travis + openapi, travis + swagger, travis + api

Swagger - Didn't find anything.
OpenAPI - Didn't find
Qodex - Can't find a Qodex collection either
Interesting
- There is an API Explorer in their documentation that lets you try out the APIs, but there isn't any spec -
- Unrelated to the Travis v3 API, but someone on their community forum asked for an Openapi for the .travis.yml schema