Router.com (Ramp Router) vs StepFun API

Router.com (Ramp Router)

Detailed Markdown docs with typed error codes, per-model capability data and routing an agent can set per request. No OpenAPI document, status page, changelog or published rate limits were found. Signup needs a US business email in a browser, and Ramp records prompts and outputs for a year by default unless switched off.

StepFun API

StepFun's API serves Step 5 Preview with a 1M-token context, video input, strict JSON Schema output and published per-token prices, documented in Markdown with an llms.txt. The model is a preview with no release date found, there's no free allowance or SLA, and the terms and privacy policy leave room to train on customer data.

Router.com (Ramp Router)

1. Switch off content recording in Settings before sending private data. It is on by default and keeps prompts and outputs for a year
2. Read model ids from GET /v1/models at runtime. Ids are account-specific, an unknown one is a 404, and Gemini ids need your own Google key
3. Use POST /v1/responses with a models list for fallbacks. Router stops falling back once a stream has started
4. Set fallback_timeout and provider_timeout, or allow_flex_tier: false, when latency matters. Flex routing is on by default
5. Treat both 401 invalid_api_key and 401 api_key_deactivated as a possibly locked key, and stop retrying on 402

StepFun API

1. Set max_tokens yourself. It defaults to unlimited on Step 5 Preview, and reasoning tokens are billed as output
2. Use response_format with type: json_schema and strict: true when the shape matters. JSON Mode alone isn't schema-checked
3. Back off and retry on 429, 500, 503 and 504. The docs give no Retry-After header or backoff schedule
4. Expect HTTP 451 or finish_reason: content_filter when content fails StepFun's review, and don't retry the same input
5. Use api.stepfun.ai for the international platform. api.stepfun.com is the China platform with yuan pricing