Rejection Reasons

X-Fairvisor-Reason is set on reject responses.

Core reasons

Reason	Meaning
no_bundle_loaded	No active bundle is loaded
kill_switch	Request matched an active kill switch
token_bucket_exceeded	Token bucket denied request
budget_exceeded	Cost budget exhausted
circuit_breaker_open	Policy circuit breaker is open
loop_detected	Loop detector threshold exceeded

LLM-specific reasons

Reason	Meaning
prompt_tokens_exceeded	Prompt estimate exceeded max prompt limit
max_tokens_per_request_exceeded	Prompt + completion reservation exceeded per-request cap
tpm_exceeded	Tokens-per-minute budget exhausted
tpd_exceeded	Tokens-per-day budget exhausted

Streaming reason

completion_tokens_exceeded may appear in streaming SSE error payloads when mid-stream completion limit is hit. It is not emitted as X-Fairvisor-Reason header in the normal reject path.

Shadow mode

In shadow mode, would-reject reasons are kept in internal decision metadata while HTTP response is allow (200).