Versioning

Dated versions with codenames. Pin your integration with the Circa-Version header so behavior never changes underneath you.

Circa-Version: 2026-05-11.obsidian

If you omit the header, the request uses the latest supported versionat the time it's processed.

Why pin?

Pinning protects you from breaking changes. We never alter the shape of a released version; new fields and behaviors land in a new dated version.

Current versions

Version	Codename	Released	Status
`2026-05-11.obsidian`	Obsidian	May 11, 2026	Latest

Pin a default for a key

In the Developer portal, you can pin a specific version per API key. Requests made with that key that omit the Circa-Versionheader will use the pinned version rather than the global latest — useful for legacy integrations that you don't want to upgrade in lockstep with new keys.

Errors

A 400 Bad Request is returned if Circa-Version is set to an unknown value.

400Bad Request

{
  "statusCode": 400,
  "message": "Unknown circa-version '1999-01-01'. Supported: 2026-05-11.obsidian."
}