Claude API vs GroqCloud

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.

GroqCloud

Free plan with no card, at 30 requests a minute and 1,000 a day on gpt-oss. Four model shutdown dates between 2026-07-17 and 2026-09-21, with no stated minimum 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 the 5.x models. 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

GroqCloud

1. Call /models at start-up. Four model ids stopped working this quarter
2. Read retry-after on a 429 and the x-ratelimit-remaining-tokens header before the next call
3. Free plan allows 8,000 tokens a minute on gpt-oss, so keep prompts small or batch them
4. Don't build on Qwen 3.8 27B. It's a preview and previews can go at short notice
5. Treat a 498 as Flex capacity and retry later; 5xx responses aren't billed