Governor
Spend and routing policy before upstream cost is incurred.
Spend caps
Budget reservations run before upstream calls. Exceeded caps reject before provider spend.
Routing rules
Rules can choose provider/model based on conditions, metadata, or policy.
Shadow routing
Mirror traffic to a comparison provider without changing the primary response path.
Fallback chain
Fallback providers are explicit and guarded by circuit breaker state.
Weighted routing
Percentage splits enable gradual rollout by model/provider.
Circuit breakers
Provider failures open circuits and recover after configured checks.
Failure behavior
Governor blocks reject before upstream. Backend uncertainty fails closed for strict spend policy.