Filter MCPServerStdio server tools

[esandoval30]

Add Tool Filtering Capability to MCPServerStdio

Problem Statement

Currently, MCPServerStdio doesn't provide a mechanism to filter which tools are exposed from a given MCP Server. This means all tools from the server are always available, which may not be desirable in cases where we want to limit tool access for security or simplicity reasons.

Current Implementation

The current MCPServerStdio initialization only allows for basic configuration:

MCPServerStdio(
    params: MCPServerStdioParams,
    cache_tools_list: bool = False,
    name: str | None = None,
    client_session_timeout_seconds: float | None = 5,
)

Desired Feature

Add the ability to filter tools similar to Google ADK's implementation:

MCPServerStdio(
    params: MCPServerStdioParams,
    cache_tools_list: bool = False,
    name: str | None = None,
    client_session_timeout_seconds: float | None = 5,
    tool_filter: list[str] | None = None  # New parameter
)

Use Case Example

# Only expose specific tools from the MCP server
server = MCPServerStdio(
    params={
        "command": "uvx",
        "args": ["[email protected]"],
        "env": {...}
    },
    tool_filter=['get-neo4j-schema', 'read-neo4j-cypher']  # Only expose these tools
)

Benefits

1. Enhanced security by limiting tool access
2. Simplified tool interfaces for specific use cases
3. Better control over agent capabilities

Implementation Considerations

• The tool_filter parameter should be optional
• When not provided, maintain current behavior of exposing all tools
• Add validation to ensure filtered tools exist on the server
• Consider adding warning logs when requested tools don't exist

References

• Google ADK MCP Tools Documentation

[devtalker]

I have same issue, see 830

[DanieleMorotti]

Hi, considering that this feature has been requested multiple times, I've implemented a PR (#854 ) enabling the filtering of visible tools from an MCP server.
@rm-openai, if you have time, I'd appreciate your feedback. Let me know if you'd like to include this implementation, otherwise I'll close the PR. Thanks!