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Build and run evaluators for AI/LLM applications using Phoenix.
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Based on SOC occupation classification
| name | phoenix-evals |
| description | Build and run evaluators for AI/LLM applications using Phoenix. |
| license | Apache-2.0 |
| metadata | {"author":"oss@arize.com","version":"1.0.0","languages":"Python, TypeScript"} |
Build evaluators for AI/LLM applications. Code first, LLM for nuance, validate against humans.
| Task | Files |
|---|---|
| Setup | setup-python, setup-typescript |
| Decide what to evaluate | evaluators-overview |
| Choose a judge model | fundamentals-model-selection |
| Use pre-built evaluators | evaluators-pre-built |
| Build code evaluator | evaluators-code-{python|typescript} |
| Build LLM evaluator | evaluators-llm-{python|typescript}, evaluators-custom-templates |
| Batch evaluate DataFrame | evaluate-dataframe-python |
| Run experiment | experiments-running-{python|typescript} |
| Create dataset | experiments-datasets-{python|typescript} |
| Generate synthetic data | experiments-synthetic-{python|typescript} |
| Validate evaluator accuracy | validation, validation-evaluators-{python|typescript} |
| Sample traces for review | observe-sampling-{python|typescript} |
| Analyze errors | error-analysis, error-analysis-multi-turn, axial-coding |
| RAG evals | evaluators-rag |
| Avoid common mistakes | common-mistakes-python, fundamentals-anti-patterns |
| Production | production-overview, production-guardrails, production-continuous |
Starting Fresh:
observe-tracing-setup → error-analysis → axial-coding → evaluators-overview
Building Evaluator:
fundamentals → common-mistakes-python → evaluators-{code\|llm}-{python\|typescript} → validation-evaluators-{python\|typescript}
RAG Systems:
evaluators-rag → evaluators-code-* (retrieval) → evaluators-llm-* (faithfulness)
Production:
production-overview → production-guardrails → production-continuous
| Prefix | Description |
|---|---|
fundamentals-* | Types, scores, anti-patterns |
observe-* | Tracing, sampling |
error-analysis-* | Finding failures |
axial-coding-* | Categorizing failures |
evaluators-* | Code, LLM, RAG evaluators |
experiments-* | Datasets, running experiments |
validation-* | Validating evaluator accuracy against human labels |
production-* | CI/CD, monitoring |
| Principle | Action |
|---|---|
| Error analysis first | Can't automate what you haven't observed |
| Custom > generic | Build from your failures |
| Code first | Deterministic before LLM |
| Validate judges | >80% TPR/TNR |
| Binary > Likert | Pass/fail, not 1-5 |
Debug LLM applications using the Phoenix CLI. Fetch traces, analyze errors, review experiments, inspect datasets, and query the GraphQL API. Use when debugging AI/LLM applications, analyzing trace data, working with Phoenix observability, or investigating LLM performance issues.
OpenInference semantic conventions and instrumentation for Phoenix AI observability. Use when implementing LLM tracing, creating custom spans, or deploying to production.
