TruLens

Overview

TruLens is an open-source platform for evaluating and monitoring LLM applications, with specialized capabilities for RAG systems. It pioneered the "RAG Triad" evaluation framework that's become an industry standard.

Features

• RAG Triad Metrics: Groundedness, answer relevance, and contextual relevance
• Feedback Functions: Programmatic evaluation of application components
• Trace Visualization: Detailed execution flow tracking
• LLM-as-Judge: Use LLMs to evaluate other LLM outputs
• Component-Level Evaluation: Assess individual parts of RAG pipelines
• Real-Time Monitoring: Track application performance in production
• Custom Metrics: Define your own evaluation criteria
• Integration: Works with major LLM frameworks

RAG Triad

1. Groundedness: Whether the answer is factually consistent with the retrieved context
2. Answer Relevance: How relevant the generated answer is to the query
3. Context Relevance: How relevant the retrieved context is to the query

Use Cases

• Evaluating RAG system accuracy
• Debugging hallucination issues
• Monitoring production AI applications
• A/B testing different prompts or models
• Ensuring response quality

Integration

Supports LangChain, LlamaIndex, and custom applications. MLflow's third-party scorer framework includes TruLens alongside RAGAS and Phoenix.

Pricing

Open-source and free to use.