Skip to main content
Version: 2.0

Vectara Open Eval Framework

The Vectara Open RAG Eval framework is an open-source Python toolkit that helps developers evaluate and optimize their Retrieval-Augmented Generation (RAG) pipelines. This framework addresses a critical need for systematic RAG evaluation and optimization, enabling you to find the best model configurations and settings for your specific use cases.

Why RAG evaluation is important

Traditional approaches to RAG optimization leave developers guessing about which models, parameters, and configurations work best for their applications. The Open Eval framework provides data-driven insights to help you:

  • Optimize model selection for specific use cases and datasets
  • Fine-tune RAG parameters based on measurable performance metrics
  • Compare different configurations systematically
  • Validate improvements before deploying to production

Here are the key features of the Vectara Open RAG Eval framework:

Flexible evaluation metrics

  • Standard metrics from TREC-RAG benchmark
  • No requirement for "golden chunks" or "golden answers"
  • Research-backed techniques from University of Waterloo
  • Support for custom metric integration

Multi-platform support

  • Vectara integration (native support)
  • LlamaIndex compatibility
  • LangChain compatibility
  • Extensible architecture for other RAG platforms

Comprehensive analysis

  • Per-query scoring and detailed analysis
  • Multiple evaluation metrics including:
    • UMBRELA
    • AutoNuggetizer
    • BERT Score
    • ROUGE-L
    • Consistency evaluation across generations

Visualization tools

  • Web-based evaluation viewer at openevaluation.ai
  • Command-line plotting capabilities
  • Streamlit local viewer for interactive analysis

Solve model selection challenges

The framework directly addresses the question: "How do I know which model and settings work best for my use case?"

Before Open Eval: trial and error

  • Guessing optimal model configurations
  • No systematic comparison method
  • Difficulty validating improvements
  • Black box optimization

With Open Eval: data-driven optimization

  • Systematic evaluation across models and parameters
  • Quantifiable performance metrics
  • Clear comparison between configurations
  • Evidence-based decision making

Best Practices

Dataset creation

  • Include representative queries from your actual use case
  • Cover edge cases and common scenarios
  • Ensure diversity in query complexity and topics
  • Validate dataset quality before evaluation

Configuration testing

  • Test systematically, changing one parameter at a time
  • Include baseline configurations for comparison
  • Document all tested configurations
  • Consider cost vs. performance trade-offs

Results analysis

  • Look beyond single metrics - use multiple evaluation criteria
  • Consider statistical significance of results
  • Validate findings with real user feedback when possible
  • Monitor production performance after optimization

Continuous improvement

  • Re-evaluate periodically as your dataset evolves
  • Test new models and presets as they become available
  • Update evaluation queries based on user feedback
  • Maintain evaluation history for trend analysis

The Open Eval framework transforms RAG optimization from guesswork into a systematic, data-driven process. By providing quantifiable metrics and comparison capabilities, it enables you to confidently select the best model configurations for your specific applications and use cases.