Galileo

Galileo is an AI reliability platform that combines evaluation, observability, and guardrails for generative AI applications and agents. The pitch is a single trust layer that follows a system across its lifecycle: teams test outputs before they ship, watch them in production, and block unsafe or low quality responses at runtime, rather than stitching those concerns together from separate tools. Galileo was founded in 2021 by Vikram Chatterji, Atindriyo Sanyal, and Yash Sheth, engineers who came from Google AI, Google Brain, Apple Siri, and Uber, and it is based in San Francisco. Note that this is the evaluation company at galileo.ai, not the similarly named text to UI design tool.

What sets Galileo apart technically is Luna and Luna-2, its own family of small language models built for evaluation. Because they score at sub 200 millisecond latency and very low cost per token, teams can evaluate 100 percent of production traffic rather than sampling, which is usually too expensive with general purpose models. On top of these run more than twenty research backed evaluators covering hallucination, correctness, completeness, context adherence, RAG quality, and agent reliability, and a continuous learning workflow improves those evaluators over time using human feedback.

In 2025 Galileo shipped an agent reliability platform aimed at multi agent systems, where a single bad action can leak data or cost real money. It gives end to end visibility into every step an agent takes, with agent specific metrics like tool call tracking and instruction following, and an insights engine that clusters similar failures across traces so the root cause surfaces without manual detective work. Galileo Protect turns the same evaluators into runtime guardrails that scan prompts and responses and block violations, and integrates with NVIDIA NeMo Guardrails for added control.

Galileo runs on a usage based subscription. A free tier includes 5,000 traces a month with unlimited users and unlimited custom evaluations, the Pro tier starts at $100 a month billed yearly for 50,000 traces with role based access and advanced analytics, and Enterprise is custom with unlimited traces, single sign on, runtime guardrails, and dedicated inference servers. It deploys as SaaS, in a private cloud, or on premises. Galileo has raised about $68M, led by a Series B from Scale Venture Partners, and counts HP, Twilio, Reddit, and Comcast among its customers.