Describe the bug

I am using a runtime variable in my Agentflow, but the agent tools header can not replace it.

{
"Authorization" : "Bearer {{$vars.bearer}}"
}

And what I got on my API:
INFO 85.237.234.185:0 - "GET /protected HTTP/1.1" 401
2025-07-29 11:14:41,672 - root - INFO - Verifying token: {{ $vars.bearer }}

To Reproduce

1. Create a runtime variable
2. Add an Agent and Request GET tool
3. Add header {
   "Authorization" : "Bearer {{$vars.bearer}}"
   }
4. Use the tool

Expected behavior

The bearer token should be inserted

Screenshots

No response

Flow

No response

Use Method

None

Flowise Version

latest

Operating System

None

Browser

None

Additional context

No response