issue: Reference MCP Server (Sequential Thinking) not compatible with mcpo #38

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opened 2026-02-15 20:17:37 -05:00 by yindo · 0 comments
Owner

Originally created by @enving on GitHub (Apr 17, 2025).

Check Existing Issues

  • I have searched the existing issues and discussions.
  • I am using the latest version of mcpo.

mcpo Version

v0.0.12

Open WebUI Version (if applicable)

v0.6.5

Operating System

Ubuntu 24.04

Browser (if applicable)

Chrome

Confirmation

  • I have read and followed all instructions in README.md.
  • I am using the latest version of both MCPO and Open WebUI.
  • I have included the browser console logs.
  • I have included the Docker container logs.
  • I have listed steps to reproduce the bug in detail.

Expected Behavior

The integration of the Sequential Thinking MCP server with OpenWebUI should work correctly. When a user makes a request that requires sequential thinking, OpenWebUI should be able to call the /sequentialthinking/sequentialthinking endpoint with properly typed JSON parameters, and the tool should perform a step-by-step analysis.

Actual Behavior

The integration of the Sequential Thinking MCP server with OpenWebUI should work correctly. When a user makes a request that requires sequential thinking, OpenWebUI should be able to call the http://mcpo:8000/sequentialthinking endpoint with properly typed JSON parameters, and the tool should perform a step-by-step analysis.

We get a error in the container logs: ""Input should be a valid integer, unable to parse string as an integer"

The problem appears to be a data type incompatibility issue between OpenWebUI and the Sequential Thinking server. OpenWebUI sends parameters as strings (also for null values and booleans), while the API expects concrete types (integer, boolean, null).

Steps to Reproduce

  1. Create a Docker Compose setup with OpenWebUI and MCPO Server

  2. Configure Sequential Thinking in the config.json:

    "sequentialthinking": {
    "command": "npx",
    "args": [
    "-y",
    "@modelcontextprotocol/server-sequential-thinking"
    ]
    }

  3. Configure in Openwebui:

    • URL: http://mcpo:8000/sequentialthinking
    • Auth: Bearer Token with API Key
  4. Activate native function calling to see the status in the chat fenster or leave it off and see in container logs

  5. In a chat, ask a question that requires sequential thinking, e.g., "Analyze step by step the business model of 1komma5.com"

  6. The MCPO logs show a 422 error

The manual curl command works fine:

curl -X POST "http://localhost:8000/sequentialthinking/sequentialthinking"
-H "Content-Type: application/json"
-H "Authorization: Bearer ..."
-d '{
"thought": "I am analyzing the business model of 1komma5.com",
"nextThoughtNeeded": true,
"thoughtNumber": 1,
"totalThoughts": 5
}'

But the request generated by OpenWebUI fails.

Logs & Screenshots

Faulty request from OpenWebUI to the Sequential Thinking server:

Error Message in MCPO container logs:

docker logs mcpo

{
"error": "HTTP error 422: {"detail":[{"type":"int_parsing","loc":["body","revisesThought"],"msg":"Input should be a valid integer, unable to parse string as an integer","input":"null"},{"type":"int_parsing","loc":["body","branchFromThought"],"msg":"Input should be a valid integer, unable to parse string as an integer","input":"null"}]}"
}

Error message in UI:

Image

{
"thought": "Let's break down the business model of 1komma5.com into its key components and analyze each step in detail.",
"next_thought_needed": "True",
"thought_number": "1",
"total_thoughts": "5",
"is_revision": "False",
"revises_thought": "null",
"branch_from_thought": "null",
"branch_id": "null",
"needs_more_thoughts": "False"
}
{
"error": "HTTP error 422: {"detail":[{"type":"missing","loc":["body","nextThoughtNeeded"],"msg":"Field required","input":{"thought":"Let's break down the business model of 1komma5.com into its key components and analyze each step in detail."}},{"type":"missing","loc":["body","thoughtNumber"],"msg":"Field required","input":{"thought":"Let's break down the business model of 1komma5.com into its key components and analyze each step in detail."}},{"type":"missing","loc":["body","totalThoughts"],"msg":"Field required","input":{"thought":"Let's break down the business model of 1komma5.com into its key components and analyze each step in detail."}}]}"
}

Additional Information

No response

Originally created by @enving on GitHub (Apr 17, 2025). ### Check Existing Issues - [x] I have searched the existing issues and discussions. - [x] I am using the latest version of mcpo. ### mcpo Version v0.0.12 ### Open WebUI Version (if applicable) v0.6.5 ### Operating System Ubuntu 24.04 ### Browser (if applicable) Chrome ### Confirmation - [x] I have read and followed all instructions in `README.md`. - [x] I am using the latest version of **both** MCPO and Open WebUI. - [x] I have included the browser console logs. - [x] I have included the Docker container logs. - [x] I have listed steps to reproduce the bug in detail. ### Expected Behavior The integration of the Sequential Thinking MCP server with OpenWebUI should work correctly. When a user makes a request that requires sequential thinking, OpenWebUI should be able to call the `/sequentialthinking/sequentialthinking` endpoint with properly typed JSON parameters, and the tool should perform a step-by-step analysis. ### Actual Behavior The integration of the Sequential Thinking MCP server with OpenWebUI should work correctly. When a user makes a request that requires sequential thinking, OpenWebUI should be able to call the `http://mcpo:8000/sequentialthinking` endpoint with properly typed JSON parameters, and the tool should perform a step-by-step analysis. We get a error in the container logs: ""Input should be a valid integer, unable to parse string as an integer" The problem appears to be a data type incompatibility issue between OpenWebUI and the Sequential Thinking server. OpenWebUI sends parameters as strings (also for null values and booleans), while the API expects concrete types (integer, boolean, null). ### Steps to Reproduce 1. Create a Docker Compose setup with OpenWebUI and MCPO Server 2. Configure Sequential Thinking in the config.json: "sequentialthinking": { "command": "npx", "args": [ "-y", "@modelcontextprotocol/server-sequential-thinking" ] } 3. Configure in Openwebui: - URL: `http://mcpo:8000/sequentialthinking` - Auth: Bearer Token with API Key 4. Activate native function calling to see the status in the chat fenster or leave it off and see in container logs 5. In a chat, ask a question that requires sequential thinking, e.g., "Analyze step by step the business model of 1komma5.com" 4. The MCPO logs show a 422 error The manual curl command works fine: curl -X POST "http://localhost:8000/sequentialthinking/sequentialthinking" \ -H "Content-Type: application/json" \ -H "Authorization: Bearer ..." \ -d '{ "thought": "I am analyzing the business model of 1komma5.com", "nextThoughtNeeded": true, "thoughtNumber": 1, "totalThoughts": 5 }' But the request generated by OpenWebUI fails. ### Logs & Screenshots Faulty request from OpenWebUI to the Sequential Thinking server: Error Message in MCPO container logs: docker logs mcpo { "error": "HTTP error 422: {\"detail\":[{\"type\":\"int_parsing\",\"loc\":[\"body\",\"revisesThought\"],\"msg\":\"Input should be a valid integer, unable to parse string as an integer\",\"input\":\"null\"},{\"type\":\"int_parsing\",\"loc\":[\"body\",\"branchFromThought\"],\"msg\":\"Input should be a valid integer, unable to parse string as an integer\",\"input\":\"null\"}]}" } Error message in UI: ![Image](https://github.com/user-attachments/assets/4eddc3fc-29e3-4b70-b1e5-bfe40fc68603) { "thought": "Let's break down the business model of 1komma5.com into its key components and analyze each step in detail.", "next_thought_needed": "True", "thought_number": "1", "total_thoughts": "5", "is_revision": "False", "revises_thought": "null", "branch_from_thought": "null", "branch_id": "null", "needs_more_thoughts": "False" } { "error": "HTTP error 422: {\"detail\":[{\"type\":\"missing\",\"loc\":[\"body\",\"nextThoughtNeeded\"],\"msg\":\"Field required\",\"input\":{\"thought\":\"Let's break down the business model of 1komma5.com into its key components and analyze each step in detail.\"}},{\"type\":\"missing\",\"loc\":[\"body\",\"thoughtNumber\"],\"msg\":\"Field required\",\"input\":{\"thought\":\"Let's break down the business model of 1komma5.com into its key components and analyze each step in detail.\"}},{\"type\":\"missing\",\"loc\":[\"body\",\"totalThoughts\"],\"msg\":\"Field required\",\"input\":{\"thought\":\"Let's break down the business model of 1komma5.com into its key components and analyze each step in detail.\"}}]}" } ### Additional Information _No response_
yindo added the bug label 2026-02-15 20:17:37 -05:00
yindo closed this issue 2026-02-15 20:17:37 -05:00
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Reference: open-webui/mcpo#38