The OpenRouter Handbook

One OpenAI-compatible endpoint that routes to 400+ AI models from every major provider. Stop maintaining 7 different SDK integrations. The auth, the model selection logic, the routing patterns, the streaming shape, and the production patterns that hold up at scale.

• One OpenAI-compatible endpoint that routes to 400+ models from every major provider
• Model selection: the model ID convention, capability filters, when to pin a model versus use a fallback list
• Routing patterns: provider preference order, fallback behavior, latency vs cost vs availability trade-offs