Vercel AI Gateway is a day 0 launch partner for the OpenResponses API, an open-source specification from OpenAI for multi-provider AI interactions. OpenResponses provides a unified interface for text generation, streaming, tool calling, image input, and reasoning across providers. AI Gateway supports OpenResponses for: Use OpenResponses with your AI Gateway key, and switch models across providers by changing the model string. You can also use OpenResponses for more complex cases, like tool calling. Read the or .OpenResponses API documentationview the specification Read more Send messages and receive responses from any supported model.Text generation: Receive tokens as they're generated via server-sent events.Streaming: Define functions that models can invoke with structured arguments.Tool calling: Send images alongside text for vision-capable models.Image input: Enable extended thinking with configurable effort levels.Reasoning: Configure automatic fallback chains across models and providers.Provider fallbacks: