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@arizeai/phoenix-evals provides evaluator building blocks for TypeScript workflows. It includes LLM-based evaluators, code-based evaluators, prompt templating helpers, and compatibility points for Phoenix experiments.

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Install

@arizeai/phoenix-evals depends on model adapters from the AI SDK ecosystem. Install the package plus at least one provider adapter for the models you plan to use. 
npm install @arizeai/phoenix-evals

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Common Setups

npm install @arizeai/phoenix-evals @ai-sdk/openai

npm install @arizeai/phoenix-evals @ai-sdk/google
You can also pair it with Phoenix experiments: 
npm install @arizeai/phoenix-evals @arizeai/phoenix-client @ai-sdk/openai

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Runtime Expectations

  • Node.js 18+
  • an AI SDK provider package such as @ai-sdk/openai
  • credentials required by your chosen provider

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Minimal Example

import { openai } from "@ai-sdk/openai";
import { createFaithfulnessEvaluator } from "@arizeai/phoenix-evals";

const faithfulness = createFaithfulnessEvaluator({
  model: openai("gpt-4o-mini"),
});

const result = await faithfulness.evaluate({
  input: "What is Phoenix?",
  context: "Phoenix is an open-source AI observability platform from Arize.",
  output: "Phoenix is an open-source AI observability platform from Arize.",
});

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Docs And Source In node_modules

After install, a coding agent can inspect the installed package directly: 
node_modules/@arizeai/phoenix-evals/docs/
node_modules/@arizeai/phoenix-evals/src/
The bundled docs cover evaluator creation, LLM evaluators, templates, classification, and Phoenix integration.

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Where To Start

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Source Layout

  • src/index.ts re-exports the package surface you usually import from @arizeai/phoenix-evals
  • src/llm/ contains classification helpers and built-in LLM evaluator factories
  • src/helpers/ contains createEvaluator and evaluation-result helpers
  • src/template/ contains formatTemplate and getTemplateVariables
  • src/types/ contains shared evaluator and prompt types

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Source Map

  • src/index.ts
  • src/llm/
  • src/helpers/
  • src/template/
  • src/core/
  • src/types/