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Claude Agent SDK

Official agent SDK by Anthropic

open sourceupdated Jul 14, 2026

Anthropic's Python SDK for building agentic AI applications powered by Claude models. Provides primitives for creating agents with tool use, multi-step reasoning, guardrails, handoffs between specialized agents, and structured output. Supports building complex agent workflows with tracing and observability. Designed for developers building production AI agents that interact with external systems, databases, and APIs using Claude as the reasoning backbone.

The Claude Agent SDK is an official framework from Anthropic for building AI agents that autonomously read files, run commands, search the web, edit code, and more, using the same tools, agent loop, and context management that power Claude Code. It solves the challenge of building production-grade autonomous agents by providing a battle-tested runtime in both Python and TypeScript that handles tool execution, context window management, error recovery, and multi-step reasoning out of the box. The SDK enables developers to create agents with the same capabilities and reliability that Anthropic uses internally for their flagship coding agent product.

The Claude Agent SDK includes subagent support for delegating specialized tasks, hooks for automatically triggering actions at specific points in the agent lifecycle, structured outputs with JSON schema validation, and file checkpointing with rewind capabilities for exploring different approaches or recovering from unwanted changes. Custom tools are implemented as in-process MCP servers that run directly within the application, eliminating the need for separate processes. The compact feature automatically summarizes previous messages when the context limit approaches, ensuring agents can handle long-running sessions without running out of context.

The Claude Agent SDK is designed for developers and engineering teams building autonomous coding agents, research assistants, data processing pipelines, and workflow automation systems powered by Claude models. It integrates with the Anthropic API including extended context window support and provides a familiar development experience for teams already using Claude Code. The SDK is particularly well-suited for building agents that need to interact with local file systems, execute shell commands, manage codebases, and perform complex multi-step tasks requiring the sophisticated reasoning capabilities of Claude models.

Pricing

Free (API usage-based)

Platforms

Python, TypeScript

Categories

Tags

Use Cases

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Comparisons

FAQ

What is Claude Agent SDK?

Anthropic's Python SDK for building agentic AI applications powered by Claude models. Provides primitives for creating agents with tool use, multi-step reasoning, guardrails, handoffs between specialized agents, and structured output. Supports building complex agent workflows with tracing and observability. Designed for developers building production AI agents that interact with external systems, databases, and APIs using Claude as the reasoning backbone.

Is Claude Agent SDK free?

Yes — Claude Agent SDK is open source and free to use. Free (API usage-based)

Is Claude Agent SDK open source?

Yes — Claude Agent SDK is open source.

What are the best Claude Agent SDK alternatives?

The top editor-verified Claude Agent SDK alternatives are OpenAI Agents SDK, LangChain, Mastra.