Claude API vs SiliconFlow

Claude API

Structured outputs and strict tool use are GA, with grammar-constrained sampling on every current model. Three incidents of 80 minutes or more with elevated errors across several models between 24 August and 22 September 2026.

SiliconFlow

Per-token prices for every listed model are public, and one key reaches chat, embeddings, reranking, image, video and speech through OpenAI-style and Anthropic-style routes. No status page, SLA, security page or official SDK was found, release notes stop at 11 June 2026, and several model removals are dated the same day as their notice.

Claude API

1. Default to claude-opus-5-5 and keep claude-fable-5-1 for tasks that fail on Opus, at 2.5 times the price
2. Don't send tool_choice any or tool to Opus 5.5, Sonnet 5.5 or Fable 5.1. Use auto with strict: true on the tool
3. Put cache_control on the system prompt and tool list. Reads cost 0.05x input on Opus 5.5
4. Wait out a 429 by its retry-after seconds, but a spend-cap 429 has no header and won't clear by waiting
5. Move off claude-sonnet-4-5-20250929 before 2026-11-30. Retired ids fail, they don't redirect

SiliconFlow

1. Set the OpenAI client's base URL to https://api.siliconflow.com/v1, or the Anthropic client's to https://api.siliconflow.com/, and send the key as a Bearer token
2. Take model ids from the model pages or GET /v1/models, not from the OpenAPI enum or the function calling guide, which list removed models
3. Check the model field of each response. On 11 June 2026 traffic for GLM-5 and Kimi-K2.5 was routed to successor models
4. Use response_format of json_object only where the model page says JSON Mode is supported, and keep max_tokens about 10,000 below the context length
5. Set the Claude Code environment variables by hand. The automated route pipes a script from an Amazon S3 bucket into bash