Slot Expired¶
This is not a Problem type, and it is not a USP error code. No USP operation emits slot_expired, and there is no https://usp-protocol.dev/errors/slot-expired URI to branch on. This page exists so that older links resolve to the correct replacement.
The condition it described - a held slot that expired before the booking could be completed - is reported as hold_expired, a business outcome code carried with HTTP 200 OK:
- REST: an entry in the response body's
messages[]array. - MCP: an entry in
result.structuredContent.messages[].
Severity is recoverable: the hold is gone, but the platform can query availability again and place a new hold.
See the business outcome code registry in specification Section 9.4.2, and Section 4.2 for hold lifetime rules.