Is there an OpenAPI spec/schema for the API?

Yes, AssemblyAI publishes an OpenAPI 3.1.0 specification for the REST API:

openapi.yaml — OpenAPI 3.1.0 spec (YAML)
openapi.json — OpenAPI 3.1.0 spec (JSON)

The spec covers all REST API endpoints including file upload, transcript submission and retrieval, and the LLM Gateway. You can use the spec to generate client libraries, validate requests, or import into tools like Postman.

Is there a way for us to send the start time / end time for transcription instead of transcribing the whole length of a call recording?

What causes a "read operation timed out" error?

⌘I