Response Metadata

Every successful response includes a routing_metadata object with details about how the request was routed and its cost. Only publicly stable fields are listed below. Internal fields classified as HIDDEN in sdk-exposure.yaml are stripped at the API boundary and are not part of the public contract.

Field	Type	Required	Description
`cost`	CostInfo	No	Cost for the request
`cost.usd`	number	Yes	Billable cost in USD
`model_canonical`	string	Yes	Canonical model ID requested
`provider`	string	Yes	Provider name (e.g., “fireworks_ai”, “anthropic”)
`provider_model_id`	string	Yes	Provider’s model ID
`routing_strategy`	string	Yes	Strategy used for routing. Known values: `cost`, `cost-focus`, `ttft`, `ttft-focus`, `tps`, `tps-focus`, `balanced`, `custom`. `custom` is returned when explicit `routing.weights` are provided. Additional strategies may be added in future versions.
`ttft_ms`	number	No	Time to first token (streaming only)
`warnings`	string[]	No	Warnings about ignored/unsupported configuration

Public Contract