MCP client does not send dynamic Bearer token when tools selection is not set to "all"

[redosk]

Bug Description

When connecting to an MCP server that uses Bearer authentication to dynamically filter the data it can access depending on the user communicating with my agent, the auth token is not sent when using a tool selection instead of all.

I've defined a Bearer credential with the following expression:
{{ $('B_01 - Trigger: Phase A Output').item.json.session.metadata.userToken ?? 'PERM_TOKEN_WITH_NO_DATA_ACCESS_RIGHTS' }}

The fallback permanent token defined in this expression is used when the node has no userToken, so n8n can communicate with the MCP server to list its tools before the trigger node is populated.

When the tool selection is set to all, everything works correctly. However, when I try to select specific tools, it does not work.

I also tried creating a second Bearer credential using only the permanent token. I use this credential to make the tool selection and then switch back to the dynamic credential. However, when the agent later tries to use the MCP server, it still does not work: no Authorization header is sent to the MCP server.

To Reproduce

1. Create a workflow with an AI Agent that has an MCP Client configured as a tool.

2. Configure the MCP Client to use a new Bearer credential.

3. Set the credential value to an expression that references a value produced by a previous node, with a fallback value, for example :
   {{ $('Trigger Node').item.json.session.metadata.userToken ?? 'PERM_TOKEN_WITH_NO_DATA_ACCESS_RIGHTS' }}

4. Try to list the available tools.

Expected behavior

The client should send the Authorization: Bearer PERM_TOKEN_WITH_NO_DATA_ACCESS_RIGHTS header to the MCP server when attempting to list the available tools.

Debug Info

Debug info

core

• n8nVersion: 2.0.3
• platform: docker (self-hosted)
• nodeJsVersion: 22.21.0
• nodeEnv: production
• database: sqlite
• executionMode: regular
• concurrency: -1
• license: enterprise (production)
• consumerId: de537fb0-6c0e-436e-81f2-1100fc03e62b

storage

• success: all
• error: all
• progress: false
• manual: true
• binaryMode: filesystem

pruning

• enabled: true
• maxAge: 336 hours
• maxCount: 10000 executions

client

• userAgent: mozilla/5.0 (windows nt 10.0; win64; x64) applewebkit/537.36 (khtml, like gecko) chrome/143.0.0.0 safari/537.36
• isTouchDevice: false

Generated at: 2025-12-18T16:18:06.969Z

Operating System

Ubuntu 24.04.3 LTS

n8n Version

2.0.3

Node.js Version

22.21.0

Database

SQLite (default)

Execution mode

main (default)

Hosting

self hosted

[n8n-assistant]

Hey @redosk,

Thank you for reaching out! We’ve received your issue and are looking into it. To help us track this internally, we’ve created a Linear ticket with the reference: "GHC-5974".

We’ll keep you updated as we make progress, but if you have any additional details or context to share, feel free to add them here - it’s always helpful!

Thanks for your patience and for bringing this to our attention.

---

For INTERNAL use only: GHC-5974

[n8n-assistant]

Hi @redosk 👋

Thanks so much for your patience while we’ve been improving n8n. We know it’s taken some time to review this issue, and we’re currently updating our triage process to better keep up with our growth.

There have been a lot of improvements in recent releases, so we’d really appreciate it if you could check whether this issue still occurs in the latest release.

When you have a moment, please copy and paste the checklist below as a comment so our system can update the status automatically:

[ ] I have updated to the latest stable version of n8n [please specify version number] and I am still experiencing this issue
[ ] Please close this issue – I am no longer experiencing it
[ ] Please close this issue – [please specify a reason]

If we don’t hear from you in the next 14 days this issue will be automatically closed, feel free to reopen - don’t forget to add the checklist above so that our automated systems notify us of the issue.

Thanks again for helping us keep n8n healthy and up-to-date 💚

[lramming]

Interesting, I have the same issue but it always happens, even when I allow for all tools. I am running a self-hosted Version 2.2.3

[n8n-assistant]

As we haven’t heard back from you, we’re going to close this issue to keep things organized. But don’t worry, if you have more information or need further assistance, you’re welcome to reopen the issue anytime or create a new one. We’re always happy to help!

Thanks for reaching out and have a great day! If this was closed by mistake and you have been waiting for us let me know and I can also re-open it.