May 27, 2026
Product changes
- Series B announcement -- Published the $113M Series B announcement.
- API tab redesign on model pages -- Each model's API tab now shows the
/responsesand/messagesendpoint references alongside/chat/completions, making it easier to discover alternative request formats. Docs - Presets: Anthropic Messages API support -- Created presets from inference now support
POST /api/v1/presets/:slug/messages, the Anthropic Messages counterpart to the existing chat/completions preset route. Docs - Stream inactivity timeout -- Streaming requests that produce no chunks for 30 seconds are now aborted immediately instead of waiting up to 5 minutes, catching dead connections and empty streams faster.
- Guardrails API documentation -- Added a guide for updating your workspace default guardrail programmatically via the API. Docs
- Fixed: EU routing for non-Google models on Vertex -- Non-Google models (Claude, Llama, DeepSeek, etc.) routed through
eu.openrouter.ainow use the correct endpoint path, fixing 400 errors caused by a hostname/path mismatch.
Fetched June 4, 2026
