Cohere API
API for Cohere's Command (generation) and Embed (embeddings) models. Strong focus on enterprise search, RAG, and classification use cases.
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.