Quickstart

Use the Agent SDK to build an AI agent that reads your code, finds bugs, and fixes them, all without manual intervention. What you’ll do:

Set up a project with the Agent SDK
Create a file with some buggy code
Run an agent that finds and fixes the bugs automatically

Prerequisites

Node.js 18+ or Python 3.10+
An Anthropic account. If you don’t have one, sign up here.

Setup

Create a project folder

Create a new directory for this quickstart:

mkdir my-agent
cd my-agent

For your own projects, you can run the SDK from any folder; it will have access to files in that directory and its subdirectories by default.

Install the SDK

Install the Agent SDK package for your language:

TypeScript (new project)
TypeScript (existing project)
Python (uv)
Python (pip)

npm init -y
npm pkg set type=module
npm install @anthropic-ai/claude-agent-sdk
npm install --save-dev tsx

Setting "type": "module" in package.json lets your agent script use top-level await, and tsx runs TypeScript files directly. npm prints added N packages when the install succeeds.

npm install @anthropic-ai/claude-agent-sdk
npm install --save-dev tsx

tsx runs TypeScript files directly. If your project uses CommonJS, name your agent script agent.mts instead of agent.ts. The .mts extension makes tsx treat the file as an ES module, so top-level await works without converting your whole project to ES modules. Use agent.mts in place of agent.ts in the create and run steps later in this quickstart.

uv is a fast Python package manager that handles virtual environments automatically:

uv init
uv add claude-agent-sdk

Create and activate a virtual environment, then install the package.On macOS or Linux:

python3 -m venv .venv
source .venv/bin/activate
pip install claude-agent-sdk

On Windows:

py -m venv .venv
.venv\Scripts\Activate.ps1
pip install claude-agent-sdk

If PowerShell blocks Activate.ps1 with an execution policy error, run Set-ExecutionPolicy -Scope Process RemoteSigned first.

Both the TypeScript and Python SDKs bundle a native Claude Code binary, so most installs need no separate Claude Code install. Some installs have no bundled binary:

If pip installs the Python SDK’s source distribution instead of a platform wheel, for example on ARM64 Windows, no binary is bundled. Install Claude Code natively. The Python SDK finds it on your PATH.
The TypeScript SDK installs its binary through npm optional dependencies, so an install that skips them, for example npm ci --omit=optional, gets no binary even on a supported platform. Reinstall without skipping optional dependencies, or install Claude Code natively and set pathToClaudeCodeExecutable to its path.

Set your API key

Get an API key from the Claude Console, then set it as an environment variable in the shell where you’ll run your agent:

macOS / Linux
Windows (PowerShell)

export ANTHROPIC_API_KEY=your-api-key

$env:ANTHROPIC_API_KEY = "your-api-key"

The SDK reads the key from the environment of the process that runs your agent; it doesn’t load .env files automatically. If you keep the key in a .env file, load it yourself, for example with the dotenv package, before calling the SDK.The SDK also supports authentication via third-party API providers:

Amazon Bedrock: set CLAUDE_CODE_USE_BEDROCK=1 environment variable and configure AWS credentials
Claude Platform on AWS: set CLAUDE_CODE_USE_ANTHROPIC_AWS=1 and ANTHROPIC_AWS_WORKSPACE_ID, then configure AWS credentials
Google Cloud’s Agent Platform: set CLAUDE_CODE_USE_VERTEX=1 environment variable and configure Google Cloud credentials
Microsoft Foundry: set CLAUDE_CODE_USE_FOUNDRY=1 environment variable and configure Azure credentials

See the setup guides for Amazon Bedrock, Claude Platform on AWS, Google Cloud’s Agent Platform, or Microsoft Foundry for details.

Agent SDK

Core concepts

Input and output

Extend with tools

Customize behavior

Control and observability

Deployment

SDK references

Prerequisites

Setup

​Prerequisites

​Setup

Prerequisites

Setup