Top LLM Integration & Prompt Engineering Companies

LLM integration and prompt engineering is the work of putting a large language model, such as GPT, Claude, Gemini or Llama, inside an existing product or workflow so that it answers correctly from your own data. The firms build retrieval-augmented generation (RAG) over documents and databases, write and version the prompts, connect the model to tools and APIs, and set up evaluations and guardrails that catch wrong or unsafe output. Companies hire them when a chatbot demo works but fails on real questions, or when support, sales or operations teams want AI features in tools they already use.

Compare the firms here on shipped production features rather than demos, how they measure answer quality, and how they handle data privacy.