Langfuse traces every LLM call with costs and latencies, manages prompt versions, and runs evals — the ops layer for AI features, self-hostable free.
Langfuse
Open-source LLM observability: traces, evals, prompt management
langfuse.com · OSS free; cloud free tier
Capabilities
Capabilities
- Tracing, token/cost analytics, prompt versioning, evals, datasets; OSS or cloud free tier
Best for
- Any clone with LLM features you intend to improve after launch
Not for
- Products with no AI calls to observe