Experiments

Master LLM and AI application experiments with comprehensive tutorials covering the Fiddler Evals SDK, custom evaluators, model comparison, and custom experiment creation.

Building reliable AI applications requires systematic evaluation to ensure quality, safety, and consistent performance. This section provides comprehensive tutorials and quick starts to help you evaluate your LLM applications, RAG systems, and AI agents using Fiddler Experiments.

circle-info

New to Fiddler Experiments? Start with Getting Started with Fiddler Experimentsarrow-up-right to understand the core concepts and interface before diving into these tutorials.

What You'll Learn

These tutorials cover the full spectrum of experiment capabilities in Fiddler:

New to Fiddler Experiments? Follow this progression:

  1. Getting Started with Fiddler Experimentsarrow-up-right - Understand the why and what (15 min read)

  2. Evals SDK Quick Startarrow-up-right - Build your first experiment (20 min hands-on)

  3. Advanced Patterns - Master production patterns (45 min hands-on)

  4. Evals SDK Reference - Complete SDK documentation (reference)

Evaluating RAG applications? Follow this path:

  1. RAG Health Diagnosticsarrow-up-right - Understand the RAG diagnostic triad (15 min read)

  2. RAG Health Metrics Tutorial - Evaluate RAG systems with Answer Relevance 2.0, Context Relevance, and RAG Faithfulness (30 min hands-on)

  3. RAG Evaluation Fundamentals Cookbook - End-to-end RAG evaluation use case

Already familiar with Fiddler Experiments? Jump to the Fiddler Evals SDK Reference for API details.


Fiddler Evals SDK Quick Start

Get hands-on with the Fiddler Evals SDK in 20 minutes. Learn to create experiment datasets, use built-in evaluators (Answer Relevance, Coherence, Toxicity), build custom evaluators, and run comprehensive experiments with detailed analysis.

Perfect for: Developers new to the Fiddler Evals SDK who want to understand experiment workflows quickly.

Start the Quick Startarrow-up-right

RAG Health Metrics Tutorial

Evaluate RAG applications using the diagnostic triad: Answer Relevance 2.0, Context Relevance, and RAG Faithfulness. Learn to identify whether issues stem from retrieval, generation, or query understanding, and run experiments to compare pipeline configurations.

Perfect for: Teams building or maintaining RAG applications who need systematic evaluation and root cause analysis.

Start the RAG Health Tutorial

Fiddler Evals SDK Advanced Guide

Master advanced evaluation patterns for production LLM applications. Explore complex data import strategies, context-aware evaluators for RAG systems, multi-score evaluators, lambda-based parameter mapping, and production-ready experiment patterns with 11+ evaluators.

Perfect for: Teams building production experiment pipelines with sophisticated requirements.

Explore Advanced Patterns

Compare LLM Outputs

Learn how to systematically compare outputs from different LLM models (like GPT-3.5 and Claude) to determine the most suitable choice for your application. This guide demonstrates side-by-side model comparison workflows using Fiddler's evaluation framework.

Perfect for: Teams evaluating multiple models or prompt variations to make data-driven decisions.

Compare Models

Prompt Specs Quick Start

Create custom LLM-as-a-Judge evaluations in minutes using Prompt Specs. Learn to define evaluation schemas using JSON, validate and test your evaluations, and deploy custom evaluators to production monitoring—all without manual prompt engineering.

Perfect for: Teams needing domain-specific evaluation logic without extensive prompt-tuning effort.

Create Custom Evaluations

Key Experiment Capabilities

Comprehensive Test Suites

Create datasets with test cases covering real-world scenarios, edge cases, and expected behaviors. Import data from CSV, JSONL, or pandas DataFrames with flexible column mapping.

Built-in Evaluators

Access production-ready evaluators for common evaluation tasks:

  • Quality: Answer Relevance 2.0 (ordinal scoring), Coherence, Conciseness, Completeness

  • RAG Health: Answer Relevance 2.0, Context Relevance, RAG Faithfulness — the diagnostic triad for RAG pipeline evaluation

  • Safety: Toxicity Detection, Prompt Injection, PII Detection

  • Context-Aware: FTL Faithfulness for RAG systems (Fast Trust Model)

  • Sentiment: Multi-score sentiment and topic classification

  • Pattern Matching: Regex-based format validation

Custom Evaluation Logic

Build evaluators tailored to your domain using:

  • Python-based evaluators with the Evaluator base class

  • Prompt Specs for schema-based LLM-as-a-Judge evaluation

  • Multi-score evaluators returning multiple metrics per test case

  • Function wrappers for existing evaluation functions

Experiment Management

Run comprehensive experiments with:

  • Parallel processing for faster evaluation across large datasets

  • Detailed results tracking with scores, timing, and error handling

  • Metadata tagging for experiment organization and filtering

  • Side-by-side comparison to validate improvements

Production Integration

Deploy evaluations to production monitoring:

  • Enrichment pipeline integration for real-time evaluation

  • Automated alerting based on evaluation metrics

  • Dashboard visualization for tracking quality trends

  • Historical tracking to monitor improvements over time

Enterprise Experiment Features

Team Collaboration

  • Shared experiment libraries: Reuse datasets and evaluators across teams

  • Access control: Project-level and application-level permissions

  • Experiment tracking: Compare evaluations across team members and versions

Production Integration

  • CI/CD pipelines: Automated evaluation before deployment

  • Quality gates: Set score thresholds that must be met for deployment

  • Regression detection: Alert when experiment scores drop

Compliance & Auditing

  • Evaluation history: Complete audit trail of all experiments

  • Reproducibility: Frozen datasets and evaluators for regulatory compliance

  • Export capabilities: Download results for external analysis and reporting

Experiment Use Cases

Single-Turn Q&A Systems

Evaluate direct question-answering applications with relevance, correctness, and conciseness metrics.

RAG Applications

Assess context-grounded responses by checking for faithfulness, relevance, and completeness.

Multi-Turn Conversations

Evaluate dialogue systems with coherence, context retention, and conversation quality metrics.

Agentic Workflows

Test tool-using agents with trajectory evaluation, tool selection accuracy, and task completion metrics.

Getting Started Paths

For SDK Users:

For Custom Evaluation Needs:

  1. Understand LLM Evaluation Prompt Specs concepts

  2. Explore Advanced Prompt Specs patterns

For Model Selection:

  1. Set up comparison experiments with your candidate models

  2. Use evaluation metrics to make data-driven decisions

Best Practices

Start Small, Scale Systematically

Begin with a focused test suite covering critical functionality. Gradually expand coverage as you understand your application's failure modes.

Use Multiple Evaluators

Combine different evaluator types (quality, safety, domain-specific) for a comprehensive assessment. No single metric captures all aspects of AI application quality.

Track Over Time

Establish baselines and monitor evaluation metrics as your application evolves. Systematic tracking reveals degradation before it impacts users.

Leverage Metadata

Tag test cases with categories, difficulty levels, and business context. Rich metadata enables targeted analysis and root cause investigation.

Automate Evaluation

Integrate evaluations into CI/CD pipelines and deploy to production monitoring. Continuous evaluation prevents quality regressions and maintains user trust.