google--adk-python/contributing/samples/mcp/mcp_in_agent_tool_remote

AgentTool with MCP Demo (SSE Mode)

This demo shows how AgentTool works with MCP (Model Context Protocol) toolsets using SSE mode.

SSE vs Stdio Mode

This demo uses SSE (Server-Sent Events) mode where the MCP server runs as a separate HTTP server:

• Remote connection - Connects to server via HTTP
• Separate process - Server must be started manually
• Network communication - Uses HTTP/SSE for messaging

For the stdio (subprocess) version, see mcp_in_agent_tool_stdio.

Setup

Start the MCP simple-tool server in SSE mode (in a separate terminal):

# Run the server using uvx (no installation needed)
# Port 3000 avoids conflict with adk web (which uses 8000)
uvx --from 'git+https://github.com/modelcontextprotocol/python-sdk.git#subdirectory=examples/servers/simple-tool' \
    mcp-simple-tool --transport sse --port 3000

The server should be accessible at http://localhost:3000/sse.

Running the Demo

adk web contributing/samples

Then select mcp_in_agent_tool_remote from the list and interact with the agent.

Try These Prompts

This demo uses Gemini 2.5 Flash as the model. Try these prompts:

1. Check available tools:

   What tools do you have access to?
   

2. Fetch and summarize JSON Schema specification:

   Use the mcp_helper to fetch https://json-schema.org/specification and summarize the key features of JSON Schema
   

Architecture

main_agent (root_agent)
  │
  └── AgentTool wrapping:
        │
        └── mcp_helper (sub_agent)
              │
              └── McpToolset (SSE connection)
                    │
                    └── http://localhost:3000/sse
                          │
                          └── MCP simple-tool server
                                │
                                └── Website Fetcher Tool

Related

• Issue: #1112 - Using agent as tool outside of adk web doesn't exit cleanly
• Related Issue: #929 - LiteLLM giving error with OpenAI models and Grafana's MCP server
• Stdio Version: mcp_in_agent_tool_stdio - Uses local subprocess connection