Remove the ANTHROPIC_MODEL_MAP layer — /v1/messages now uses the same model names as /v1/chat/completions (deepseek-v4-flash-free, gpt-5.4-mini-no-login, deepseek/deepseek-v4-flash). This way users send the original model name and it routes to the correct backend. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>