{"library":"langfuse","type":"library","category":null,"description":"Open-source LLM observability and evaluation platform. Python SDK provides tracing via @observe decorator, OpenTelemetry integration, and a low-level client for manual trace/span management. Works with any LLM framework — not tied to LangChain. Self-hostable (Docker/Kubernetes) or cloud (EU/US regions). MAJOR VERSION NOTE: SDK was completely rewritten in v3 (released June 2025). v3 is OpenTelemetry-based with a new singleton client pattern. All v2 import paths, class names, and initialization patterns are broken in v3. pip install langfuse installs v3 as of Feb 2026.","language":"python","status":"active","version":"3.14.5","tags":["langfuse","tracing","observability","llm-monitoring","opentelemetry","evaluation","self-hosted","open-source"],"last_verified":"Tue Jun 09","install":[{"cmd":"pip install langfuse","imports":["from langfuse import Langfuse, get_client","from langfuse.decorators import observe","from langfuse.langchain import CallbackHandler"]},{"cmd":"pip install 'langfuse<3'","imports":[]}],"homepage":"https://langfuse.com","github":null,"docs":null,"changelog":null,"pypi":"https://pypi.org/project/langfuse/","npm":null,"openapi_spec":null,"status_page":null,"smithery":null,"compatibility":{"summary":{"python_range":"3.10–3.9","success_rate":75,"avg_install_s":5.7,"avg_import_s":1.87,"wheel_type":"wheel"},"url":"https://checklist.day/v1/registry/langfuse/compatibility"}}