Sonnet is Anthropic's balanced model for general agents and chat.
curl https://oneapikey.app/v1/v1/messages \
-H "Authorization: Bearer $ONEAPIKEY_API_KEY" \
-H "X-APIMarket-Product: claude-sonnet-4-6" \
-H "Content-Type: application/json" \
--data '{"model":"anthropic/claude-sonnet-4-6","messages":[{"role":"user","content":"hi"}]}'