Resolving Claude Opus 4.6 Thinking Model API Errors: A Complete Analysis of Format Compatibility Issues Between /v1/messages and /v1/chat/completions
Ever run into this situation: you're using the claude-opus-4-6-thinking model, and calls via /v1/chat/completions (OpenAI format) work perfectly fine, but when you switch to /v1/messages (Anthropic native format), you get the error content: Input should be a valid list? This seemingly counterintuitive phenomenon actually reveals a deep compatibility issue with the Thinking model across the … Read more
