Errors

A completed determination describes evidence support. All four determinations return 200 completed. A POST 202 in_progress is accepted work, not an error. GET returns HTTP 200 for stored in_progress, completed, and failed states, so always inspect status.

Frozen HTTP mappings

HTTP	Meaning	Response
`401`	Missing/invalid credential, including credential lookup failure.	Check authentication.
`403`	Revoked, expired, wrong-client credential, or unauthorized organization.	Check the credential and organization with support.
`404`	Missing or cross-organization GET ID.	Check the saved validation ID and organization.
`409`	Payload/idempotency conflict, active duplicate without async acceptance, or a failed execution that cannot reuse this key.	Reconcile identity and state; see Idempotency.
`422`	Invalid request, path, or header schema.	Correct input using the API Reference.
`429`	Credential rate limit or enforced VU capacity exhausted.	Inspect usage and `Retry-After` when present.
`500`	Sanitized direct evaluation/internal failure.	Preserve request identity and investigate; unhandled errors may be plain text.
`502`	Source Inspection failure.	Inspection fails closed, with no completed determination or VU charge.
`503`	State, accounting, or retrieval unavailable; hybrid evaluation unavailable/interrupted.	Preserve identity; reconcile availability before another attempt.
`504`	Hybrid upstream timeout.	Inspect the stored failure through GET when an ID is available.

Direct qualified provider failures retain the compatible 500 mapping; 504 describes hybrid timeout behavior.

Sanitized hybrid failures

A ValidationExecutionFailure contains validation_id, status: "failed", and error with code and message.

`error.code`	POST HTTP	GET HTTP
`upstream_timeout`	504	200
`provider_unavailable`	503	200
`inspection_failed`	502	200
`execution_interrupted`	503	200
`capacity_exhausted`	429	200
`internal_failure`	500	200

Other errors commonly use detail; 422 uses a structured validation-error body. Parse defensively and handle plain text. Do not depend on provider exception internals or turn execution failure into determination: "uncertain".

A transport failure may leave the outcome unknown. Retrieve by ID or deliberately replay the same request/key according to Idempotency. Do not blindly retry POSTs with a new key.

Advanced workflows

Technical Session, generation, workflow, and artifact routes retain route-specific errors and review metadata. A successful workflow may still require human review or have a skipped action. Consult its operation in the API Reference; those workflow states do not replace VI determinations.