Claude Code Python SDK Package Guide

Building a Python SDK package for Claude Code opens up powerful automation possibilities. This guide walks you through creating, structuring, and publishing a Python package that integrates with Claude Code workflows.

Setting Up Your Python SDK Project

Before diving into code, ensure you have Python 3.9+ and the latest version of Claude Code installed. Create a new directory for your SDK and initialize it with proper tooling.

mkdir claude-sdk-mypackage && cd claude-sdk-mypackage
python3 -m venv venv
source venv/bin/activate

The foundation of any Claude Code Python SDK begins with a well-structured pyproject.toml file. This configuration defines your package metadata, dependencies, and build settings.

[build-system]
requires = ["setuptools>=61.0", "wheel"]
build-backend = "setuptools.build_meta"

[project]
name = "claude-sdk-mypackage"
version = "0.1.0"
description = "SDK for extending Claude Code workflows"
requires-python = ">=3.9"
dependencies = [
    "requests>=2.28.0",
    "pydantic>=2.0.0",
]

[project.optional-dependencies]
dev = ["pytest", "black", "mypy"]

Core Package Structure

Organize your SDK with a clean, modular structure. The src layout prevents import issues and follows modern Python packaging best practices.

claude-sdk-mypackage/
├── src/
│   └── mypackage/
│       ├── __init__.py
│       ├── client.py
│       ├── models.py
│       └── utils.py
├── tests/
├── pyproject.toml
└── README.md

The __init__.py should expose your public API clearly. Clients should only import what they need directly from your package root.

# src/mypackage/__init__.py
from .client import ClaudeClient
from .models import Request, Response

__all__ = ["ClaudeClient", "Request", "Response"]
__version__ = "0.1.0"

Building the Client Interface

A reliable SDK needs a clean client interface. Use type hints throughout and use pydantic for request/response validation. This approach catches errors early and provides excellent IDE support.

# src/mypackage/client.py
from typing import Optional
from pydantic import BaseModel
import requests

class ClaudeClient:
    def __init__(self, api_key: str, base_url: str = "https://api.claude.ai"):
        self.api_key = api_key
        self.base_url = base_url
        self.session = requests.Session()
        self.session.headers.update({"Authorization": f"Bearer {api_key}"})

    def complete(self, prompt: str, model: str = "claude-3") -> str:
        response = self.session.post(
            f"{self.base_url}/v1/completions",
            json={"prompt": prompt, "model": model}
        )
        response.raise_for_status()
        return response.json()["completion"]

This pattern works well for basic integrations. For more complex workflows, consider adding connection pooling, retry logic, and async support using httpx or aiohttp.

Integrating Claude Skills

Your SDK can use existing Claude skills to extend functionality. Skills like frontend-design help generate UI components, while pdf handles document processing. The tdd skill assists with test-driven development workflows.

# Using skills within your SDK
def generate_tests(client: ClaudeClient, code: str) -> str:
    prompt = f"""Using the tdd skill pattern, generate unit tests for:
{code}

Follow pytest conventions and include setup/teardown."""
    return client.complete(prompt, model="claude-3-sonnet")

The supermemory skill enables persistent context across sessions. Your SDK can tap into this for maintaining conversation history or user preferences.

def save_context(client: ClaudeClient, key: str, value: dict):
    """Store context using supermemory pattern."""
    client.session.post(
        f"{client.base_url}/v1/memory",
        json={"key": key, "value": value, "skill": "supermemory"}
    )

Publishing Your Package

Once your SDK is ready, publishing to PyPI makes it available to the community. Create an account at pypi.org and install the necessary tools.

pip install build twine
python -m build
twine upload dist/*

Version management matters. Follow semantic versioning and document changes in a CHANGELOG. Users should understand what changed between versions.

Testing Your SDK

Comprehensive testing builds confidence. Use pytest with fixtures for mocking API responses.

# tests/test_client.py
import pytest
from mypackage import ClaudeClient

@pytest.fixture
def mock_client(monkeypatch):
    class MockResponse:
        def json(self):
            return {"completion": "test response"}
        def raise_for_status(self):
            pass
    
    def mock_post(self, url, json=None):
        return MockResponse()
    
    monkeypatch.setattr(requests.Session, "post", mock_post)
    return ClaudeClient(api_key="test-key")

def test_complete(mock_client):
    result = mock_client.complete("Hello")
    assert result == "test response"

Run tests with coverage reporting to ensure critical paths work correctly.

pytest --cov=mypackage --cov-report=html

Best Practices

Keep these principles in mind throughout development. Type hints improve discoverability and catch errors early. Document public APIs thoroughly using docstrings. Handle errors gracefully with meaningful exceptions rather than exposing raw API errors.

Consider supporting both sync and async interfaces. Many modern applications use asyncio, and offering both options increases your SDK’s usefulness.

import asyncio
from httpx import AsyncClient

class AsyncClaudeClient:
    async def complete(self, prompt: str) -> str:
        async with AsyncClient() as client:
            response = await client.post(
                f"{self.base_url}/v1/completions",
                json={"prompt": prompt},
                headers={"Authorization": f"Bearer {self.api_key}"}
            )
            return response.json()["completion"]

Conclusion

Building a Python SDK for Claude Code follows established patterns. Focus on clean interfaces, thorough testing, and good documentation. Use skills like pdf for document handling or tdd for generating tests automatically. Start simple, iterate based on user feedback, and publish when ready.

The Python ecosystem benefits from well-designed packages. Your SDK contributes to that ecosystem and enables others to build powerful Claude Code integrations.

Built by theluckystrike — More at zovo.one