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petr

v0.1.1

Published

PETR allows you to run multiple models with the same prompt and then compare the results to each other. Currently designed to be used with [LangChain.js](https://github.com/hwchase17/langchainjs).

Readme

PETR (Prompt Engineering Test Reporter)

PETR allows you to run multiple models with the same prompt and then compare the results to each other. Currently designed to be used with LangChain.js.

Installation

pnpm add petr

Usage

import {
  ChatPromptTemplate,
  HumanMessagePromptTemplate,
  PromptTemplate,
  SystemMessagePromptTemplate,
} from 'langchain/prompts';
import { runner } from 'petr';

const CHAT_PROMPT = new ChatPromptTemplate({
  promptMessages: [
    new SystemMessagePromptTemplate(
      new PromptTemplate({
        template: `You are JokeBot. You are a bot that tells jokes!`,
      })
    ),
    new HumanMessagePromptTemplate(
      new PromptTemplate({
        template: `{input}`,
        inputVariables: ['input'],
      })
    ),
  ],
  inputVariables: ['input'],
});

const STANDARD_PROMPT = new PromptTemplate({
  template: `${systemPrompt}\n\nuser: {input}\nJokeBot:`,
  inputVariables: ['input'],
});

export const PROMPT_SELECTOR = /*#__PURE__*/ new ConditionalPromptSelector(
  CHAT_PROMPT,
  [[isLLM, STANDARD_PROMPT]]
);

await runner({
  prompt: PROMPT_SELECTOR,
  data: [{ input: 'tell me a joke!' }, { input: 'What else can you tell me?' }],
  csvParams: { path: 'jokes.csv' },
  loadChainFn: (llm, promptSelector) =>
    LLMChain({
      prompt: promptSelector.getPrompt(llm),
      llm,
      outputKey: 'output',
    }),
  models: [
    {
      name: 'gpt-4',
      llm: new ChatOpenAI({ temperature: 0.9, modelName: 'gpt-4' }),
    },
    {
      name: 'gpt-35',
      llm: new ChatOpenAI({ temperature: 0.9, modelName: 'gpt-3.5-turbo' }),
    },
  ],
});

This will then output a jokes.csv file that should look like the following:

input,gpt-4,gpt-35
tell me a joke!,What do you call a cow with no legs?,What do you call a cow with no legs?
What else can you tell me?,What do you call a cow with no legs?,What do you call a cow with no legs?