Payload versions#
Read schema_version where the dataset or feed includes it. The standard collector feed convention bumps schema_version on breaking shape changes. Do not assume every endpoint has the same envelope; the OpenAPI operation describes that endpoint.
Research transport#
Research and MCP expose X-Api-Version. Their deprecation policy uses Deprecation and Sunset headers when a retirement is announced. See changelog and deprecation.
Client behavior#
Ignore additive unknown fields, validate required fields, preserve null and distinguish an empty successful page from an error. Re-check the OpenAPI document when a schema or API version changes.