OpenAI API
API access to GPT-5, GPT-5.5, o3/o4 reasoning models, and the Responses API; plus embeddings, image, audio, and Realtime endpoints. The most widely deployed LLM API in production.
Mistral API
API access to Mistral's model lineup including Mistral Large for frontier capability and Mistral Small 4 — a 2026 unification of the Magistral, Pixtral, and Devstral lines into a single multimodal model. Strong open-weight strategy alongside the managed API.