Remote MCP on Railway (1 click deploy) will not complete last part of authentication (using notion as test)

[jteusa]

I'm trying to add notion remote MCP on my Librechat, deployed on Railway (1 click deploy) and amd having issues.

• Using librechat.yaml file
• MCP config info is below
• Notion shows in UI, starts auth > goes thru notion > returns to success call back url > redirects back to UI
• But the auth isn't complete (i.e. UI shows to start auth again)

Read thru some discussions hacking around, but can't get it to work.

• Is there something specific missing here in the yaml?
• Or maybe something I didn't add in Variables at Railway?

So close to doing what I want to do (it's not notion, it's another mcp) but I'm stuck.

Thanks!

notion:
   type: streamable-http
   url: "https://mcp.notion.com/sse"
   oauth: 
     redirect_uri: "https://librechatdomain.com/api/mcp/notion/oauth/callback" # removed url
   serverInstructions: true
   timeout: 30000
   initTimeout: 10000

[jteusa]

FML. I changed to type: sse and worked. Could've sworn I tried that earlier at some point. But it's working now.

[ahmedriaz12]

I dug in and here’s what’s going on:.

The (high-level) Fix @jteusa

1. UI filtering: only render upload options that are actually enabled. Example: if runCode: false, don’t show Code upload at all.
2. Always keep a text path: include ocr in capabilities so non-image files can still inject as plain text.
3. Backend respect for mode: if user picks as_text, always OCR-to-context regardless of whether Search/Tools are on.

Example Config

interface:
  runCode: false
agents:
  capabilities:
    - tools
    - ocr     # keep text ingestion alive
  # removed: execute_code, file_search

Pseudocode (UI + Server)

// UI (AttachMenu)
if (caps.includes('ocr')) opts.push('as_text');
if (caps.includes('file_search')) opts.push('file_search');
if (caps.includes('execute_code') && ui.runCode) opts.push('code');

// Server (uploadController)
switch (mode) {
  case 'as_text': return ocrExtract(file);
  case 'file_search': return indexForRAG(file);
  case 'code': return stageForSandbox(file);
  case 'image': return attachImage(file);
}

[ahmedriaz12]

Boss, the Expected UX
• Normal chat: PDF attaches directly as text (no confusing menu).
• With Search: menu shows Text + File Search, both work.
• With Code: Code option only if runCode:true.
• With MCP tool only: user still gets Image + Text and non-image files succeed…

This way the attach menu never offers a path the backend can’t handle, and every visible option is guaranteed to work…