Langfuse

Langfuse is an open-source LLM engineering platform designed to help teams build and improve production-grade LLM applications faster. It addresses key challenges such as debugging complex workflows, monitoring costs and latencies, and assessing output quality. Langfuse provides comprehensive tools for tracing the full execution flow of LLM applications, including API calls, retrieved context, prompts, and parallelism. It offers hierarchical representations, multi-modal support, and detailed metrics on cost and latency. The platform also facilitates user feedback, automated LLM-as-a-judge evaluations, manual data labeling, and robust prompt management for experimentation. It supports versioning and testing via curated datasets, providing quantitative insights to enhance LLM applications. Langfuse is used by tens of thousands of developers globally.