Errors and support

• 400 invalid input or policy violation.
• 401 missing or invalid authentication.
• 403 authenticated but not permitted.
• 404 absent or out-of-scope resource.
• 409 state or version conflict.
• 429 rate limit exceeded.
• 5xx service or dependency failure.

For support, capture the UTC timestamp, request ID, endpoint, status, and stable error code. Never include credentials or sensitive request bodies.