mcpengine/infra/factory-tools/mcp-validator/mcp_testing/protocols

Copyright (c) 2025 Scott Wilcox

SPDX-License-Identifier: AGPL-3.0-or-later

MCP Protocol Versions

This directory contains the implementation of different MCP protocol versions for the testing framework. Each version implements the specific requirements and capabilities of that protocol version.

Components

• base.py: Base protocol class defining common functionality across versions
• v2024_11_05.py: Implementation of the 2024-11-05 protocol version
• v2025_03_26.py: Implementation of the 2025-03-26 protocol version

Protocol Interface

Each protocol version extends the base MCPProtocol class, which defines a common interface for interacting with different protocol versions:

class MCPProtocol:
    def get_version(self):
        """Get the protocol version string."""
        pass
        
    def get_initialize_params(self):
        """Get parameters for the initialize request."""
        pass
        
    def check_initialization_response(self, response):
        """Validate an initialization response."""
        pass
        
    def validate_tool_list(self, tools_list):
        """Validate a tools list response."""
        pass
        
    def get_spec_requirements(self):
        """Get a list of specification requirements for this version."""
        pass

Protocol Version Features

2024-11-05 (Initial Version)

The initial protocol version with:

• Basic synchronous tool calls
• Simple initialization/shutdown flow
• Base tool requirements

2025-03-26 (Latest Version)

The updated protocol version adding:

• Asynchronous tool support with toolCallId and status
• Session management via sessionId
• Resources API capabilities
• Enhanced error handling

Adding New Protocol Versions

To add a new protocol version:

1. Create a new file (e.g., v2026_01_15.py)
2. Extend the MCPProtocol base class
3. Implement all required methods
4. Add specific tests for new features in that version
5. Update __init__.py to expose the new version

Example of a new protocol version implementation:

from .base import MCPProtocol

class MCP2026_01_15Protocol(MCPProtocol):
    def get_version(self):
        return "2026-01-15"
        
    def get_initialize_params(self):
        params = {
            "protocolVersion": self.get_version(),
            "clientInfo": {
                "name": "MCP Testing Framework",
                "version": "1.0.0"
            },
            "capabilities": {
                "tools": {
                    "asyncSupported": True
                },
                "resources": True,
                "newFeature": True  # New capability introduced in this version
            }
        }
        return params
        
    # ... other method implementations ...

Usage Example

from mcp_testing.protocols import get_protocol
from mcp_testing.transports import HTTPTransport

# Get the protocol implementation for a specific version
protocol = get_protocol("2025-03-26")

# Create a transport
transport = HTTPTransport("http://localhost:9000/mcp")

# Use the protocol with the transport
initialize_params = protocol.get_initialize_params()
success, response = transport.initialize(initialize_params)

# Validate the response according to protocol requirements
if protocol.check_initialization_response(response):
    print("Server successfully initialized with protocol version", protocol.get_version())