Helicone

Helicone is an open-source LLM observability platform that sits as a proxy between applications and AI API providers, logging all API calls for monitoring, analysis, and cost management. The platform's proxy architecture makes integration simple — a single URL change routes all API calls through Helicone without changing application logic.

The platform's cost tracking capabilities provide detailed visibility into AI API spending across different models, features, users, and time periods. For organizations managing AI API costs across multiple applications and teams, this granular cost visibility is essential for budget management and optimization.

Helicone's request logging captures complete records of every AI API call including prompts, model parameters, responses, latency, token counts, and custom metadata. This comprehensive logging supports debugging, auditing, and analysis without requiring custom logging infrastructure in each application.

The platform's caching capability stores and serves repeated identical prompts from cache rather than making new API calls, reducing both costs and latency for applications with repetitive queries. This caching can provide significant cost savings for applications where many users ask similar questions.

Helicone's open-source architecture allows self-hosting for organizations with data privacy requirements that prevent sending API call data to third-party services. The self-hosted option provides the platform's observability capabilities without any data leaving the organization's infrastructure.