## Summary
Adds in-process SDK MCP server support to the Python SDK, building on
the control protocol from #139.
**Note: Targets `dickson/control` branch (PR #139), not `main`.**
## Key Changes
- Added `@tool` decorator and `create_sdk_mcp_server()` API for defining
in-process MCP servers
- SDK MCP servers run directly in the Python process (no subprocess
overhead)
- Moved SDK MCP handling from Transport to Query class for proper
architectural layering
- Added `McpSdkServerConfig` type and integrated with control protocol
## Example
```python
from claude_code_sdk import tool, create_sdk_mcp_server
@tool("greet", "Greet a user", {"name": str})
async def greet_user(args):
return {"content": [{"type": "text", "text": f"Hello, {args['name']}!"}]}
server = create_sdk_mcp_server(name="my-tools", tools=[greet_user])
options = ClaudeCodeOptions(mcp_servers={"tools": server})
```
## Testing
- Added integration tests in `test_sdk_mcp_integration.py`
- Added example calculator server in `examples/mcp_calculator.py`
---------
Co-authored-by: Dickson Tsai <dickson@anthropic.com>
Co-authored-by: Ashwin Bhat <ashwin@anthropic.com>
Co-authored-by: Claude <noreply@anthropic.com>