Kapa.ai
Managed RAG platform purpose-built for technical documentation. 200+ enterprise customers including OpenAI, Sentry, Docker, and Monday.com — the clear leader in technical-docs RAG in 2026.
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.