Helicone.ai

Helicone is an open-source LLM observability and AI gateway platform founded in 2023 and headquartered in San Francisco, California. The company was built to give developers visibility into the behavior, cost, and performance of applications that call large language model APIs.

Helicone's primary product is a proxy-based gateway that sits between an application and LLM providers such as OpenAI, Anthropic, and others. It captures request and response data to provide logging, cost tracking, latency monitoring, prompt management, and caching. The platform supports a self-hosted deployment option as well as a managed cloud service, and its core codebase is available on GitHub under an open-source license.

The company is early-stage and was part of Y Combinator's 2023 batch. The team remains small, operating with a headcount in the single digits. Helicone has gained traction among developers building production LLM applications who require structured observability tooling without building custom logging infrastructure.