---
title: "Claude Agent SDK — Overview"
aliases: [claude-agent-sdk, claude-code-sdk, agent-sdk-overview]
tags: [anthropic, claude, agent-sdk, python, typescript, ai-agents]
sources: [raw/Agent SDK overview 1.md, raw/Agent SDK overview.md]
created: 2026-04-17
updated: 2026-04-17
---

# Claude Agent SDK — Overview

Formerly the **Claude Code SDK**. Gives you the same tools, agent loop, and context management that power Claude Code — programmable in Python and TypeScript.

> Migration note: if you used the old Claude Code SDK, see the Migration Guide.

## What It Is

The Agent SDK wraps Claude with **built-in tool execution**. Unlike the raw Anthropic Client SDK where you implement your own tool loop, the Agent SDK handles the loop autonomously:

```python
# Client SDK — you manage the loop
response = client.messages.create(...)
while response.stop_reason == "tool_use":
    result = your_tool_executor(response.tool_use)
    response = client.messages.create(tool_result=result, **params)

# Agent SDK — Claude handles tools autonomously
async for message in query(prompt="Fix the bug in auth.py"):
    print(message)
```

## Quickstart (Python)

```python
import asyncio
from claude_agent_sdk import query, ClaudeAgentOptions

async def main():
    async for message in query(
        prompt="Find and fix the bug in auth.py",
        options=ClaudeAgentOptions(allowed_tools=["Read", "Edit", "Bash"]),
    ):
        print(message)

asyncio.run(main())
```

## Built-in Tools

| Tool | What it does |
|------|-------------|
| **Read** | Read any file in the working directory |
| **Write** | Create new files |
| **Edit** | Make precise edits to existing files |
| **Bash** | Run terminal commands, scripts, git operations |
| **Monitor** | Watch a background script, react to each output line as an event |
| **Glob** | Find files by pattern (`**/*.ts`, `src/**/*.py`) |
| **Grep** | Search file contents with regex |
| **WebSearch** | Search the web for current information |
| **WebFetch** | Fetch and parse web page content |
| **AskUserQuestion** | Ask the user clarifying questions with multiple-choice options |

## Claude Code Features Available in SDK

The SDK loads `.claude/` config from the working directory and `~/.claude/` by default. Use `setting_sources` / `settingSources` to restrict which sources load.

| Feature | Description | Location |
|---------|-------------|----------|
| Skills | Specialized capabilities defined in Markdown | `.claude/skills/*/SKILL.md` |
| Slash commands | Custom commands for common tasks | `.claude/commands/*.md` |
| Memory | Project context and instructions | `CLAUDE.md` or `.claude/CLAUDE.md` |
| Plugins | Extend with custom commands, agents, MCP servers | Programmatic via `plugins` option |

Also supports: **Hooks**, **Subagents**, **MCP**, **Permissions**, **Sessions**.

## Model Requirements

- Opus 4.7 (`claude-opus-4-7`) requires Agent SDK **v0.2.111 or later**
- If you see a `thinking.type.enabled` API error → update the SDK

## Agent SDK vs Client SDK

| | Client SDK | Agent SDK |
|--|------------|-----------|
| Tool loop | You implement | Claude handles |
| Setup | Direct API access | Built-in tool execution |
| Best for | Fine-grained control | Autonomous agents |

## Branding (for partners)

- **Allowed:** "Claude Agent", "Claude", "Powered by Claude"
- **Not permitted:** "Claude Code" or "Claude Code Agent", Claude Code ASCII art

## Key Takeaways

- The Agent SDK = Claude Code's internals as a library (Python + TypeScript)
- No need to implement your own tool loop — Claude handles tool execution autonomously
- All Claude Code features available: skills, memory, MCP, hooks, subagents
- Tool permissions are set via `allowed_tools` in `ClaudeAgentOptions`
- Config auto-loads from `.claude/` and `~/.claude/` — restrict with `setting_sources`
- Opus 4.7 needs SDK v0.2.111+
- Governed by Anthropic's Commercial Terms of Service

## Related

- [[wiki/tech-patterns/python-ai-agents|Python AI Agents]] — Claude/Gemini/OpenAI integration patterns used in Oliver projects
- [[wiki/architecture/_index|Architecture]] — multi-agent AI patterns and how agents are structured in production
- [[wiki/obsidian-rag/_index|Obsidian RAG]] — another agentic pattern: LLM-navigable knowledge base

## Sources

- `raw/Agent SDK overview 1.md` — clipped from code.claude.com/docs/en/agent-sdk/overview (2026-04-17)
- `raw/Agent SDK overview.md` — duplicate clip, same source page (2026-04-17)