Potential Tool Name Collision For create_file

Mar 12, 2025 by ADMIN 48 views

Introduction

When creating a tool called "create_file" using the MCP (Machine Controller Protocol) framework, a strange problem arises when using it via Claude Desktop with no other MCP servers installed. The issue is not related to the tool's functionality or the supporting code, but rather to the name of the tool itself. In this article, we will explore the potential tool name collision for "create_file" and provide a solution to resolve the issue.

The Problem

The tool definition is as follows:

createFileTool := mcp.NewTool("create_file",
    mcp.WithDescription("Creates a new file"),
    mcp.WithString("file", mcp.Required(), mcp.Description("The path of the file to create.")),
)

And the supporting code is:

s.AddTool(createFileTool, createFileHandler)

func createFileHandler(ctx context.Context, request mcp.CallToolRequest) (*mcp.CallToolResult, error) {
    filePath, ok := request.Params.Arguments["file"].(string)
    if !ok {
        return mcp.NewToolResultError("file must be a string"), nil
    }

    f, err := os.Create(filePath)
    if err != nil {
        return mcp.NewToolResultError(fmt.Sprintf("Error creating file '%s': %v", filePath, err)), nil
    }
    f.Close()

    return mcp.NewToolResultText(fmt.Sprintf("File '%s' created successfully", filePath)), nil
}

However, when using the tool via Claude Desktop, it fails to execute due to errors around the parameters. The error message consistently shows the following schema:

[
  {
    "code": "invalid_type",
    "expected": "string",
    "received": "undefined",
    "path": [
      "path"
    ],
    "message": "Required"
  },
  {
    "code": "invalid_type",
    "expected": "string",
    "received": "undefined",
    "path": [
      "file_text"
    ],
    "message": "Required"
  }
]

The Solution

After struggling to resolve the issue, the fix turned out to be surprisingly simple:

createFileTool := mcp.NewTool("create_filee",

By changing the tool name to anything other than "create_file", the issue is resolved. However, changing it back breaks it again. This suggests that the name "create_file" is colliding with an existing tool of Claude's or something.

Investigation

To investigate further, I tried changing the name of the server to "Filesystemm" but the behavior persisted. This suggests that the issue is not related to the server name, but rather to the tool name itself.

Conclusion

In conclusion, the potential tool name collision for "create_file" is a real issue that can cause problems when using the MCP framework. By changing the tool name to anything other than "create_file", the issue is resolved. This suggests that the name "create_file" is colliding with an existing tool of Claude's or something. Further investigation is needed to determine the root cause of the issue.

Recommendations

Based on the findings, the following recommendations can be made:

When creating a tool, choose a unique name that does not collide with existing tools.
If you encounter issues with a tool, try changing its name to see if it resolves the issue.
Further investigation is needed to determine the root cause of the issue and to prevent similar collisions in the future.

Config

For reference, the config used in this example is:

{
    "mcpServers": {
        "Filesystem": {
            "command": "filesystem",
            "args": [
            ]
        }
    }
}

Q: What is a tool name collision?

A: A tool name collision occurs when two or more tools have the same name, causing conflicts and issues when using them. In the case of the "create_file" tool, the name collision is causing problems when using it via Claude Desktop.

Q: Why is the "create_file" tool name causing issues?

A: The exact reason for the issue is not clear, but it is believed to be related to an existing tool of Claude's or something. Changing the tool name to anything other than "create_file" resolves the issue, suggesting that the name is colliding with an existing tool.

Q: How can I prevent tool name collisions?

A: To prevent tool name collisions, choose a unique name for your tool that does not collide with existing tools. You can also try changing the name of the tool to see if it resolves any issues.

Q: What should I do if I encounter issues with a tool?

A: If you encounter issues with a tool, try changing its name to see if it resolves the issue. If the issue persists, further investigation is needed to determine the root cause of the problem.

Q: Is the config related to the issue?

A: No, the config does not seem to be related to the issue. Changing the server name did not resolve the problem, suggesting that the issue is related to the tool name itself.

Q: What are the implications of tool name collisions?

A: Tool name collisions can cause problems when using tools, including errors and issues with functionality. In the case of the "create_file" tool, the issue is causing problems when using it via Claude Desktop.

Q: How can I determine if a tool name collision is occurring?

A: To determine if a tool name collision is occurring, try changing the name of the tool to see if it resolves any issues. If the issue persists, further investigation is needed to determine the root cause of the problem.

Q: What are the best practices for naming tools?

A: The best practices for naming tools include choosing a unique name that does not collide with existing tools. You should also try to choose a name that is descriptive and easy to understand.

Q: Can tool name collisions be prevented?

A: Yes, tool name collisions can be prevented by choosing a unique name for your tool that does not collide with existing tools. You can also try changing the name of the tool to see if it resolves any issues.

Q: What should I do if I suspect a tool name collision?

A: If you suspect a tool name collision, try changing the name of the tool to see if it resolves the issue. If the issue persists, further investigation is needed to determine the root cause of the problem.

Q: How can I report a tool name collision?

A: If you suspect a tool name collision, you can report it to the relevant authorities or the tool's maintainers. They can then investigate the issue and take steps to prevent it from happening in the future.