Using an MCP client to call the `@modelcontextprotocol/server-filesystem` server, a parameter validation error occurs

[applesline]

Describe the bug
When using an MCP client to call the @modelcontextprotocol/server-filesystem server, a parameter validation error occurs. The server incorrectly expects a name field in the params object, but according to the MCP protocol, name should be at the top level of the call object.

To Reproduce
Steps to reproduce the behavior:

1. Install required packages:

npm install @mcpilotx/sdk-core

2. Create reproduction script reproduce-bug.js:

const { MCPClient, createMCPConfig } = require('@mcpilotx/sdk-core');

async function reproduceBug() {
  const config = createMCPConfig('stdio', {
    command: 'npx',
    args: ['@modelcontextprotocol/server-filesystem', '.'],
    autoConnect: false,
    timeout: 10000
  });
  
  const client = new MCPClient(config);
  await client.connect();
  
  try {
    const result = await client.callTool('read_text_file', {
      path: './package.json'
    });
    console.log('Success:', result);
  } catch (error) {
    console.log('Error message:', error.message);
    console.log('Full error:', error);
  }
  
  await client.disconnect();
}

reproduceBug();

3. Run the script:

node reproduce-bug.js

4. Observe the error output.

Expected behavior
According to the MCP protocol specification, the correct structure for a tool call request should be:

{
  "jsonrpc": "2.0",
  "id": "1",
  "method": "tools/call",
  "params": {
    "call": {
      "name": "read_text_file",
      "arguments": {
        "path": "./package.json"
      }
    }
  }
}

The name field should be in the params.call object, not directly in the params object.

Logs
Running the reproduction script produces the following error:

Error message: [
  {
    "expected": "string",
    "code": "invalid_type",
    "path": [
      "params",
      "name"
    ],
    "message": "Invalid input: expected string, received undefined"
  }
]

The error message shows that the server is validating params.name, which indicates the server expects the name field to be directly in the params object, not in params.call.

Additional context

• MCP Protocol Reference: According to the Model Context Protocol specification, the params object of a tool call request should contain a call field, and the call field contains name and arguments
• Impact Scope: This bug affects all tool calls to @modelcontextprotocol/server-filesystem using standard MCP clients
• Workaround: Currently no workaround is available as this is a server-side validation logic issue
• Test Environment:
  • Node.js version: v22.17.1
  • @modelcontextprotocol/server-filesystem version: Unknown (npx doesn't show version with --version flag)
  • Operating System: macOS
  • MCP Client: @mcpilotx/sdk-core 0.3.3
• Note: The server successfully connects and lists 14 available tools, but all tool calls fail with the same validation error

Suggested Fix
Fix the server-side parameter validation logic to correctly parse MCP protocol request structure:

1. Validate params.call.name instead of params.name
2. Ensure compliance with MCP protocol specification