OpenAI API vs RouterPlus

OpenAI API

Official OpenAPI document and an llms.txt index. Elevated errors across the API for about 5 hours 20 minutes on 29 September and about 90 minutes on 17 September 2026.

RouterPlus

The docs are written for agents, every model price is public, and each response carries its own cost. No terms of service, privacy policy, status page or changelog were found. Signup adds no free credit, and the chat catalogue is Claude and GPT only.

OpenAI API

1. Build on the Responses API. Astra calls tools only there
2. Use gpt-6-luna for routing and extraction and gpt-6.1-sol for most work. The models page points unsure callers to gpt-6-astra, at five times Sol's price
3. Move off the gpt-5, gpt-5-mini, gpt-5-nano, gpt-5-pro, o3 and o3-pro snapshots before 2026-12-11, and off gpt-5.1, gpt-5.3-codex and gpt-5.4-nano before 2027-04-01
4. Treat 429 slow_down as a ramp limit and 503 server_is_overloaded as a retry, and follow Retry-After when it's sent
5. Prompts over 272K tokens cost double on input. Trim before you pay for it

RouterPlus

1. Send max_tokens on every request. Without it the balance hold assumes up to 32,768 output tokens and can return insufficient_quota on a small balance
2. Switch on error_type. Retry rate_limit after retry-after, and stop on insufficient_quota, which needs a person to add credit or raise a cap
3. Don't add a retry loop on top of the SDK's. There is no idempotency key, so a retry that reaches a provider is billed again
4. Copy model ids from GET /v1/models or /api/models.json. An unknown id is a 404 and the gateway never substitutes one
5. Use /v1/messages for Claude when you need thinking or server tools, and /v1/chat/completions with response_format only for GPT ids