claude-code-js

Claude Code JS

A JavaScript SDK for integrating with Claude Code, Anthropic's official CLI tool for Claude.

Overview

This project provides a JavaScript/TypeScript SDK that allows developers to programmatically interact with Claude Code, enabling AI-powered software engineering capabilities in their applications.

Installation

npm install claude-code-js

or with yarn:

yarn add claude-code-js

Quick Start

Basic Setup

import { ClaudeCode } from 'claude-code-js';

// Initialize the SDK
const claude = new ClaudeCode({
  apiKey: process.env.CLAUDE_API_KEY, // Optional: if already logged in
  model: 'claude-3-sonnet', // Optional: specify model
  workingDirectory: './my-project', // Optional: set working directory
  verbose: false, // Optional: enable verbose logging
  oauth: { // Optional: OAuth credentials for token refresh
      accessToken: "ACCESS_TOKENID",
      refreshToken: "REFRESH_TOKEN",
      expiresAt: EXPIRES_AT_VALUE
  }
});

Example Usage

Single Chat with Claude

// Send a chat message to Claude with a prompt
const response = await claude.chat({
  prompt: 'Explain this error: TypeError: Cannot read property of undefined',
  systemPrompt: 'You are a helpful coding assistant', // Optional
  appendSystemPrompt: 'Keep explanations concise' // Optional
});

if (response.success) {
  console.log('Result:', response.message.result);
  console.log('Session ID:', response.message.session_id);
  console.log('Cost:', response.message.cost_usd);
} else {
  console.error('Error:', response.error.message);
}

Sessions for Multi-turn Conversations

// Create a new session for ongoing conversations
const session = claude.newSession();

// Start the conversation
const firstMessage = await session.prompt({
  prompt: 'What is 2 + 2?',
  systemPrompt: 'You are expert at math. Always return a single line of text in format: equation = result'
});

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