[Bug]: MCP server not working any more

[kmaustral]

Bug Description

I received a Server Disconnected notification from Claude Desktop for TaskNotes MCP.

I generate a new API key and put it in the Integrations tab of TaskNotes settings. I restart Claude but the same notification appear.

This is the error log:

2026-09-14T01:25:18.592Z [Tasknotes] [info] Message from client: method="initialize" id=0 params { metadata: undefined }
[6868] Connection error: ServerError
at parseErrorResponse (file:///C:/Users/kevin/AppData/Roaming/npm/node_modules/mcp-remote/dist/chunk-65X3S4HB.js:18528:12)
at process.processTicksAndRejections (node:internal/process/task_queues:104:5)
at async registerClient (file:///C:/Users/kevin/AppData/Roaming/npm/node_modules/mcp-remote/dist/chunk-65X3S4HB.js:18947:11)
at async authInternal (file:///C:/Users/kevin/AppData/Roaming/npm/node_modules/mcp-remote/dist/chunk-65X3S4HB.js:18585:31)
at async auth (file:///C:/Users/kevin/AppData/Roaming/npm/node_modules/mcp-remote/dist/chunk-65X3S4HB.js:18536:12)
at async StreamableHTTPClientTransport.send (file:///C:/Users/kevin/AppData/Roaming/npm/node_modules/mcp-remote/dist/chunk-65X3S4HB.js:19859:26) {
errorUri: undefined
}
[6868] Fatal error: ServerError
at parseErrorResponse (file:///C:/Users/kevin/AppData/Roaming/npm/node_modules/mcp-remote/dist/chunk-65X3S4HB.js:18528:12)
at process.processTicksAndRejections (node:internal/process/task_queues:104:5)
at async registerClient (file:///C:/Users/kevin/AppData/Roaming/npm/node_modules/mcp-remote/dist/chunk-65X3S4HB.js:18947:11)
at async authInternal (file:///C:/Users/kevin/AppData/Roaming/npm/node_modules/mcp-remote/dist/chunk-65X3S4HB.js:18585:31)
at async auth (file:///C:/Users/kevin/AppData/Roaming/npm/node_modules/mcp-remote/dist/chunk-65X3S4HB.js:18536:12)
at async StreamableHTTPClientTransport.send (file:///C:/Users/kevin/AppData/Roaming/npm/node_modules/mcp-remote/dist/chunk-65X3S4HB.js:19859:26) {
errorUri: undefined
}
Assertion failed: !(handle->flags & UV_HANDLE_CLOSING), file src\win\async.c, line 76

Steps to Reproduce

No response

TaskNotes Debug Info

Affected Task Frontmatter

Relevant Bases File Content

Relevant Settings or Customizations

No response

Console Errors or Logs

Screenshots or Screen Recording

No response

[callumalpass]

Hi @kmaustral, thanks for reporting this. I’ve reproduced the same error when Claude sends a missing or outdated API token.

TaskNotes 4.13.0 made authentication mandatory for HTTP API and MCP connections. Please copy the token that is generated after enabling the TaskNotes API and restarting Obsidian (I've attached a video showing how to do this--I wasn't sure if you were copying from this field, or pasting a Claude token into this field (the latter is the wrong approach)).

In Claude Desktop, go to Settings → Developer → Edit Config. Update your TaskNotes entry to:

  {
    "mcpServers": {
      "Tasknotes": {
        "command": "npx",
        "args": [
          "-y",
          "mcp-remote",
          "http://127.0.0.1:8080/mcp",
          "--header",
          "Authorization:${AUTH_HEADER}"
        ],
        "env": {
          "AUTH_HEADER": "Bearer YOUR_TASKNOTES_API_TOKEN"
        }
      }
    }
  }

Replace YOUR_TASKNOTES_API_TOKEN with the token from Obsidian → Settings → TaskNotes → Integrations, keeping the Bearer prefix. Change 8080 if you use a different port, and preserve any other MCP servers in that file.

I will update the tasknotes documentation to make it clearer how to do this. And please let me know if you need more guidance or if this doesn't work.

Screen.Recording.2026-09-14.165112.mp4

[kmaustral]

Yep. The step I missed was to re-start TaskNotes with a blank API field (I had populated it before with my Claude API). A note in the settings might be useful for that. The video was super useful. Much appreciated.

…

On Mon, 14 Sept 2026 at 17:06, callumalpass ***@***.***> wrote: *callumalpass* left a comment (callumalpass/tasknotes#2329) <#2329 (comment)> Hi @kmaustral <https://github.com/kmaustral>, thanks for reporting this. I’ve reproduced the same error when Claude sends a missing or outdated API token. TaskNotes 4.13.0 made authentication mandatory for HTTP API and MCP connections. Please copy the token that is generated after enabling the TaskNotes API and restarting Obsidian (I've attached a video showing how to do this--I wasn't sure if you were copying from this field, or pasting a Claude token into this field (the latter is the wrong approach)). In Claude Desktop, go to Settings → Developer → Edit Config. Update your TaskNotes entry to: { "mcpServers": { "Tasknotes": { "command": "npx", "args": [ "-y", "mcp-remote", "http://127.0.0.1:8080/mcp", "--header", "Authorization:${AUTH_HEADER}" ], "env": { "AUTH_HEADER": "Bearer YOUR_TASKNOTES_API_TOKEN" } } } } Replace YOUR_TASKNOTES_API_TOKEN with the token from Obsidian → Settings → TaskNotes → Integrations, keeping the Bearer prefix. Change 8080 if you use a different port, and preserve any other MCP servers in that file. I will update the tasknotes documentation to make it clearer how to do this. And please let me know if you need more guidance or if this doesn't work. https://github.com/user-attachments/assets/59b434b8-ae63-4621-8a01-f29e1deb61f2 — Reply to this email directly, view it on GitHub <#2329?email_source=notifications&email_token=ARTR6N3IRAR54GVEXJA5XC35O6KIVA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTKNRWGAZDQNJTGQZ2M4TFMFZW63VHNVSW45DJN5XKKZLWMVXHJLDGN5XXIZLSL5RWY2LDNM#issuecomment-5660285343>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ARTR6N42FQFE6XAFS4TXQHT5O6KIVAVCNFSNUABFKJSXA33TNF2G64TZHM4TQNJVGQZDENBXHNEXG43VMU5TKNBUGQZTANJVGMZKC5QC> . Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS <https://github.com/notifications/mobile/ios/ARTR6N4BA7JLFHIYZSNJ7435O6KIVA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTKNRWGAZDQNJTGQZ2M4TFMFZW63VHNVSW45DJN5XKKZLWMVXHJKTGN5XXIZLSL5UW64Y> and Android <https://github.com/notifications/mobile/android/ARTR6N7IZD5YS2OVBQDCBYL5O6KIVA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTKNRWGAZDQNJTGQZ2M4TFMFZW63VHNVSW45DJN5XKKZLWMVXHJLTGN5XXIZLSL5QW4ZDSN5UWI>. Download it today! You are receiving this because you were mentioned.Message ID: ***@***.***>