How to install phoenix-evals
npx skills add https://github.com/arize-ai/phoenix --skill phoenix-evalsFull instructions (SKILL.md)
Source of truth, from arize-ai/phoenix.
name: phoenix-evals description: Build and run evaluators for AI/LLM applications using Phoenix. license: Apache-2.0 compatibility: Requires Phoenix server. Python skills need phoenix and openai packages; TypeScript skills need @arizeai/phoenix-client. metadata: author: oss@arize.com version: "1.0.0" languages: "Python, TypeScript"
Phoenix Evals
Build evaluators for AI/LLM applications. Code first, LLM for nuance, validate against humans.
Quick Reference
Workflows
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)
Gating CI: evaluators-{code|llm}-{python|typescript} → integrations-{pytest|vitest-jest} → production-continuous
Production: production-overview → production-guardrails → production-continuous
Reference Categories
| 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 |
integrations-* | Run evals from test runners (pytest, Vitest, Jest) as a CI gate |
validation-* | Validating evaluator accuracy against human labels |
production-* | CI/CD, monitoring |
Key Principles
| 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 |
Related skills
More from arize-ai/phoenix and the wider catalog.
phoenix-cli
Debug LLM applications using the Phoenix CLI. Fetch traces, analyze errors, structure trace review with open coding and axial coding, inspect datasets, review experiments, query annotation configs, and use the GraphQL API. Use whenever the user is analyzing traces or spans, investigating LLM/agent failures, deciding what to do after instrumenting an app, building failure taxonomies, choosing what evals to write, or asking "what's going wrong", "what kinds of mistakes", or "where do I focus" — even without naming a technique.
phoenix-tracing
OpenInference semantic conventions and instrumentation for Phoenix AI observability. Use when implementing LLM tracing, creating custom spans, or deploying to production.