curl https://api.anthropic.com/v1/messages -H 'x-api-key: $ANTHROPIC_API_KEY' -H 'anthropic-version: 2023-06-01' -H 'Content-Type: application/json' -d '{"model":"claude-sonnet-4-20250514","max_tokens":1024,"messages":[{"role":"user","content":"hello"}]}'