mcp-execution-introspector

MCP server introspection using the official rmcp SDK.

Installation

[dependencies]
mcp-execution-introspector = "0.6"

Or with cargo-add:

cargo add mcp-execution-introspector

[!IMPORTANT] Requires Rust 1.89 or later.

Usage

Basic Introspection

use mcp_execution_introspector::Introspector;
use mcp_execution_core::{ServerId, ServerConfig};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let mut introspector = Introspector::new();

    let server_id = ServerId::new("github");
    let config = ServerConfig::builder()
        .command("npx".to_string())
        .arg("-y".to_string())
        .arg("@modelcontextprotocol/server-github".to_string())
        .env("GITHUB_TOKEN".to_string(), "ghp_xxx".to_string())
        .build();

    let info = introspector.discover_server(server_id, &config).await?;

    println!("Server: {} v{}", info.name, info.version);
    println!("Tools found: {}", info.tools.len());

    for tool in &info.tools {
        println!("  - {}: {}", tool.name, tool.description);
    }

    Ok(())
}

Accessing Tool Schemas

let info = introspector.discover_server(server_id, &config).await?;

for tool in &info.tools {
    println!("Tool: {}", tool.name);
    println!("Schema: {}", serde_json::to_string_pretty(&tool.input_schema)?);
}

[!TIP] Tool schemas are JSON Schema objects that can be used for TypeScript type generation.

Transport Support

// npx-based servers
let config = ServerConfig::builder()
    .command("npx".to_string())
    .arg("-y".to_string())
    .arg("@modelcontextprotocol/server-github".to_string())
    .build();

// Docker-based servers
let config = ServerConfig::builder()
    .command("docker".to_string())
    .arg("run".to_string())
    .arg("-i".to_string())
    .arg("--rm".to_string())
    .arg("ghcr.io/org/mcp-execution-server".to_string())
    .build();

[!NOTE] Currently supports stdio transport, which is the most common for MCP servers.

Features

• Official SDK: Uses rmcp for MCP communication
• Tool Discovery: Extract all tools from any MCP server
• Schema Extraction: Get JSON schemas for tool parameters
• Capability Detection: Discover tools, resources, prompts support
• Caching: Store discovered server information
• Security: Command validation prevents injection attacks

Types Reference

How It Works

1. Validate Config — Check server configuration for security issues
2. Spawn Process — Start MCP server via stdio transport
3. Connect — Establish rmcp client connection
4. Query — Use ServiceExt::list_all_tools() to get tools
5. Extract — Parse tool definitions and schemas
6. Cache — Store information for later retrieval

Related Crates

This crate is part of the mcp-execution workspace:

• mcp-execution-core - Foundation types (ServerId, ServerConfig)
• mcp-execution-codegen - Uses introspection results for code generation
• rmcp - Official Rust MCP SDK

MSRV Policy

Minimum Supported Rust Version: 1.89

MSRV increases are considered minor version bumps.

License

Licensed under either of Apache License 2.0 or MIT license at your option.