# Agent Guild MCP tool for ADK

Supported in ADKPythonTypeScript

[Agent Guild](https://github.com/AgentTanuki/agent-guild) provides endpoint preflight, signed reputation evidence, and pricing discovery through a hosted MCP server. Connect it with ADK's MCP toolset to inspect an external agent before deciding whether to delegate work to it.

## Use cases

- **Inspect a delegation target**: Compare an endpoint's advertised capabilities with the observations and unknowns returned by a live preflight.
- **Check costs before use**: Retrieve current paid-operation prices, callable entrypoints, and free alternatives before choosing a trust operation.
- **Review evidence limits**: Keep unavailable checks and uncertainty visible when explaining whether an endpoint is suitable for a task.

## Prerequisites

- Set up ADK and model access using the [Python](/get-started/python/) or [TypeScript](/get-started/typescript/) quickstart.

- Install MCP support for the language you use:

  ```bash
  pip install "google-adk[mcp]"
  ```

  ```bash
  npm install @google/adk "@modelcontextprotocol/sdk@^1.26.0"
  ```

The two tools in this example are free and require no Agent Guild account, API key, or wallet. Model-provider usage follows your model provider's pricing. Preflight sends the selected public endpoint URL to Agent Guild's hosted service, which probes that endpoint. Supply public URLs without embedded credentials.

## Use with agent

The tool filter exposes only endpoint preflight and pricing discovery. It does not expose registration, payment, or paid trust-read tools to the agent.

```python
from google.adk.agents import Agent
from google.adk.tools.mcp_tool import McpToolset
from google.adk.tools.mcp_tool.mcp_session_manager import StreamableHTTPConnectionParams

root_agent = Agent(
    model="gemini-flash-latest",
    name="agent_guild_preflight",
    instruction=(
        "Inspect the public agent endpoint the user supplies before delegation. "
        "Use guild_preflight and report its observations and unknowns. "
        "Use guild_paid_operations when the user asks about trust-operation prices. "
        "A preflight result is evidence, not a guarantee or permission to execute."
    ),
    tools=[
        McpToolset(
            connection_params=StreamableHTTPConnectionParams(
                url="https://agent-guild-5d5r.onrender.com/mcp",
                timeout=30,
            ),
            tool_filter=["guild_preflight", "guild_paid_operations"],
        )
    ],
)
```

```typescript
import { LlmAgent, MCPToolset } from "@google/adk";

const rootAgent = new LlmAgent({
    model: "gemini-flash-latest",
    name: "agent_guild_preflight",
    instruction:
        "Inspect the public agent endpoint the user supplies before delegation. " +
        "Use guild_preflight and report its observations and unknowns. " +
        "Use guild_paid_operations when the user asks about trust-operation prices. " +
        "A preflight result is evidence, not a guarantee or permission to execute.",
    tools: [
        new MCPToolset(
            {
                type: "StreamableHTTPConnectionParams",
                url: "https://agent-guild-5d5r.onrender.com/mcp",
            },
            ["guild_preflight", "guild_paid_operations"],
        ),
    ],
});

export { rootAgent };
```

Run the agent using the quickstart for your language. For example, ask it to inspect a public agent endpoint you operate and explain which checks were inconclusive. Then ask which paid trust operations are available and what each currently costs.

## Available tools

| Tool                    | Description                                                                                                                |
| ----------------------- | -------------------------------------------------------------------------------------------------------------------------- |
| `guild_preflight`       | Probe a public agent endpoint and return observed capabilities, evidence, and unknowns. Free without a key.                |
| `guild_paid_operations` | List current paid-operation prices, entrypoints, settlement resources, and free alternatives. This discovery call is free. |

The server also offers signed Agent Passports and paid trust reads. These are outside this example's tool filter. A signature establishes origin and integrity, not the safety of an agent's messages or the quality of future work. Paid reads such as `guild_check` require the current payment terms or funded sandbox credits; do not treat them as free preflight calls.

## Additional resources

- [Agent Guild repository and API documentation](https://github.com/AgentTanuki/agent-guild)
- [Agent Guild machine-readable service guide](https://agent-guild-5d5r.onrender.com/llms.txt)
- [MCP tools in ADK](/tools-custom/mcp-tools/)