Deprecation policy

Agents run unattended, so a breaking change has to be announced where an agent will see it, well before it lands.

• Breaking: removing or renaming an operation, a field or an error code; making an optional input required; changing a field's type or meaning. Adding an operation, an optional input or a response field is not breaking.
• Notice: a deprecated operation keeps working for at least 90 days after it is announced.
• Where it is announced: the API changelog, deprecated: true on the operation in /openapi.json, and on every response from it a Deprecation header plus a Sunset header with the date it stops answering.
• After the sunset: the operation answers 410 Gone with the typed error body and a docs_url that points at its replacement.
• Error codes are stable API. A new code is announced like a new operation, a removed one like a removed operation.

Nothing is deprecated today.

Version 1, updated 2026-10-11.