[GH-ISSUE #18233] issue: MCP Tools are not Properly Namespaced #89280

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opened 2026-05-15 14:10:23 -05:00 by GiteaMirror · 1 comment
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Originally created by @daryltucker on GitHub (Oct 11, 2025).
Original GitHub issue: https://github.com/open-webui/open-webui/issues/18233

Check Existing Issues

  • I have searched for any existing and/or related issues.
  • I have searched for any existing and/or related discussions.
  • I am using the latest version of Open WebUI.

Installation Method

Docker

Open WebUI Version

latest

Ollama Version (if applicable)

No response

Operating System

Debian 13

Browser (if applicable)

No response

Confirmation

  • I have read and followed all instructions in README.md.
  • I am using the latest version of both Open WebUI and Ollama.
  • I have included the browser console logs.
  • I have included the Docker container logs.
  • I have provided every relevant configuration, setting, and environment variable used in my setup.
  • I have clearly listed every relevant configuration, custom setting, environment variable, and command-line option that influences my setup (such as Docker Compose overrides, .env values, browser settings, authentication configurations, etc).
  • I have documented step-by-step reproduction instructions that are precise, sequential, and leave nothing to interpretation. My steps:
  • Start with the initial platform/version/OS and dependencies used,
  • Specify exact install/launch/configure commands,
  • List URLs visited, user input (incl. example values/emails/passwords if needed),
  • Describe all options and toggles enabled or changed,
  • Include any files or environmental changes,
  • Identify the expected and actual result at each stage,
  • Ensure any reasonably skilled user can follow and hit the same issue.

Expected Behavior

As a consumer and client of MCP Servers, I expect Open WebUI to properly namespace the tools and methods available upon ingestion and processing.

Actual Behavior

Open WebUI flattens all methods into a single namespace meaning....

twitter.post
zipcodelookup.post

Are collapsed down to post, clash, and cause issues.

Steps to Reproduce

{
  "mcpServers": {
    "memory": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-memory"]
    },
    "memory2": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-memory"]
    }
  }
}

Logs & Screenshots

open_webui.utils.tools:get_tools:199 - Tool tool_search_post already exists in another tools!

Additional Information

This is not the job of the MCP Server. The job of the MCP Server is to provide the tools, and no single tool has two identically named methods, because... well it cannot.

Other MCP Server clients handle this just fine, and namespace the methods under the providing tool.

The warning is also not helpful at all, simply claiming there is a method clash, without telling the User which tools are involved for resolution...
And since Inspector doesn't work against mcpo....

I am specifically seeing a lot of fetch or post clashes.

https://github.com/open-webui/mcpo/issues/242
https://github.com/modelcontextprotocol/inspector/issues/860

Originally created by @daryltucker on GitHub (Oct 11, 2025). Original GitHub issue: https://github.com/open-webui/open-webui/issues/18233 ### Check Existing Issues - [x] I have searched for any existing and/or related issues. - [x] I have searched for any existing and/or related discussions. - [x] I am using the latest version of Open WebUI. ### Installation Method Docker ### Open WebUI Version latest ### Ollama Version (if applicable) _No response_ ### Operating System Debian 13 ### Browser (if applicable) _No response_ ### Confirmation - [x] I have read and followed all instructions in `README.md`. - [x] I am using the latest version of **both** Open WebUI and Ollama. - [x] I have included the browser console logs. - [x] I have included the Docker container logs. - [x] I have **provided every relevant configuration, setting, and environment variable used in my setup.** - [x] I have clearly **listed every relevant configuration, custom setting, environment variable, and command-line option that influences my setup** (such as Docker Compose overrides, .env values, browser settings, authentication configurations, etc). - [x] I have documented **step-by-step reproduction instructions that are precise, sequential, and leave nothing to interpretation**. My steps: - Start with the initial platform/version/OS and dependencies used, - Specify exact install/launch/configure commands, - List URLs visited, user input (incl. example values/emails/passwords if needed), - Describe all options and toggles enabled or changed, - Include any files or environmental changes, - Identify the expected and actual result at each stage, - Ensure any reasonably skilled user can follow and hit the same issue. ### Expected Behavior As a consumer and client of MCP Servers, I expect Open WebUI to properly namespace the tools and methods available upon ingestion and processing. ### Actual Behavior Open WebUI flattens all methods into a single namespace meaning.... `twitter.post` `zipcodelookup.post` Are collapsed down to `post`, clash, and cause issues. ### Steps to Reproduce ```json { "mcpServers": { "memory": { "command": "npx", "args": ["-y", "@modelcontextprotocol/server-memory"] }, "memory2": { "command": "npx", "args": ["-y", "@modelcontextprotocol/server-memory"] } } } ``` ### Logs & Screenshots ``` open_webui.utils.tools:get_tools:199 - Tool tool_search_post already exists in another tools! ``` ### Additional Information This is not the job of the MCP Server. The job of the MCP Server is to provide the tools, and no single tool has two identically named methods, because... well it cannot. Other MCP Server clients handle this just fine, and namespace the methods under the providing tool. The warning is also not helpful at all, simply claiming there is a method clash, without telling the User which tools are involved for resolution... And since Inspector doesn't work against `mcpo`.... I am specifically seeing a lot of `fetch` or `post` clashes. https://github.com/open-webui/mcpo/issues/242 https://github.com/modelcontextprotocol/inspector/issues/860
GiteaMirror added the bug label 2026-05-15 14:10:23 -05:00
Author
Owner

@daryltucker commented on GitHub (Oct 11, 2025):

Hey, actually they are... no idea where that came from...

<!-- gh-comment-id:3392923641 --> @daryltucker commented on GitHub (Oct 11, 2025): Hey, actually they are... no idea where that came from...
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Reference: github-starred/open-webui#89280