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Box MCP Write Tools Appear in Schema but Return “Tool Not Found” at Runtime

  • August 28, 2026
  • 1 reply
  • 54 views

Hi everyone,

I’m testing the Box MCP Server with ChatGPT and have run into an issue specifically with write/update operations.

Read operations work normally. I can search folders, list folder contents, read file metadata, and retrieve file contents without any problem.

However, when I try to update an existing file, the MCP tool schema shows that tools such as upload_file_version and get_upload_url are available, but when ChatGPT actually invokes them, the runtime returns:

Tool upload_file_version not found

and

Tool get_upload_url not found

The affected file is a normal Markdown (.md) file in Box, and the authenticated user appears to have upload/edit permissions on the folder.

So the situation seems to be:

  • Box MCP connection/authentication works

  • Read tools work

  • The write/upload tools appear in the exposed tool list/schema

  • But those tools are not available at runtime

Has anyone encountered this behavior with the Box MCP Server?

Is there an additional Box MCP configuration, permission, feature flag, or server-side setting required to enable file-version uploads or overwrite/update operations?

I’d also be interested to know whether this is a known issue where a tool is advertised in the MCP schema but is not actually registered on the runtime side.

Thanks!

1 reply

I can independently reproduce the same issue with the Box connector in ChatGPT.

Environment:
- Box account: Individual
- ChatGPT Box connector: connected successfully
- ChatGPT connector permission setting: "Allow all actions"

The following write operations work correctly:
- upload_file — SUCCESS
- create_folder — SUCCESS
- create_file_comment — SUCCESS
- copy_file — SUCCESS

However, the following tools are exposed in the ChatGPT tool/schema definitions, but fail at runtime:

- upload_file_version
  MCP error -32602: Tool upload_file_version not found

- get_upload_url
  MCP error -32602: Tool get_upload_url not found

- update_file_properties
  MCP error -32602: Tool update_file_properties not found

I also tested additional existing-item mutation operations:

- update_folder_properties
  MCP error -32602: Tool update_folder_properties not found

- move_file
  MCP error -32602: Tool move_file not found

The test file itself reports these Box permissions:
- canUpload: true
- canRename: true
- canDelete: true
- canComment: true
- canShare: true

So this does not appear to be a general Box write-permission issue. Creating new files/folders, copying files, and adding comments all succeed. The failures are specifically occurring for multiple tools that modify existing Box items.

I also performed a comparison using the Box connector in Claude. In Claude, upload_file_version, get_upload_url, and update_file_properties are not exposed in the connector schema at all, while upload_file works successfully.

So the behavior differs between clients:

- ChatGPT: these tools are exposed in the schema, but return "Tool not found" at runtime.
- Claude: the same tools are not exposed in the schema.

This makes me suspect there may be a mismatch between the tool catalog/schema exposed to the client and the tools actually registered or available at runtime.

Could someone from Box please confirm:

1. Whether upload_file_version, get_upload_url, update_file_properties, update_folder_properties, and move_file are currently expected to work with the ChatGPT Box connector for Individual accounts.
2. Whether there is any known issue with the MCP tool registry/tool exposure for these write tools.
3. Whether this behavior depends on Box plan, Tool Access configuration, or the specific AI client.

I am happy to provide additional reproduction details if needed.

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