Easily manage and integrate multiple AI language models with a single, efficient API.

A new tool type in the OpenRouter Agent SDK lets your agent auto-resolve routine decisions and pause for human input on high-stakes ones, with two hooks and zero loop-management code.

Give any tool-calling model the ability to search the web and fetch page content on its own, with multiple search engines and fetch engines to choose from.

OpenAI doubled per-token prices with GPT-5.5 but the model is less verbose. We measured real usage to see the net cost impact.

Text-to-speech and transcription are now live on OpenRouter. Two new endpoints give you access to speech synthesis and audio transcription across multiple providers, under one API.

Introducing the new Response Caching header: enables caching identical API requests so responses come back in a tiny fraction of the time, at zero cost.