AgentBuilder: File Search node always errors (vector store works as a Tool)

What’s happening
In AgentBuilder (Web UI), any workflow I try that uses a File Search node fails with a generic “workflow failed / unknown error.”
If I point the same vector store at a Tool within an Agent node, it works fine—so the store itself seems OK. The failure only happens when it’s used as a File Search node. The problem persists even in a 1 node workflow.

My setup

  • AgentBuilder (Web UI)

  • Chrome on Windows 11

How I can reproduce it

  1. Create a vector store and add files as usual.

  2. New workflow → add File Search node → select that vector store.

  3. Use either a variable-driven query or a fixed text query (e.g., “test”).

  4. Run the workflow → it fails on the File Search node.

Extra notes

  • It also fails in a single-node workflow with only the File Search node.

  • I’ve tried multiple vector stores.

  • I’ve double-checked the node config, tried fixed queries, logged out/in, incognito, another browser, and even a brand-new workspace/workflow. Same result.

Request for help

Is anyone else experiencing this problem?

Has anyone who has got File Search nodes (not agent tools) working properly able to share any tips they have from the experience?

It should be pretty simple as there only three fields, so I don’t know where I might be going wrong if indeed the fault is at my end.

It’s never worked for me.

Error:

Workflow failed: We experienced an error while running the workflow. Sorry about that! You can retry your request, or contact us through our help center at help.openai.com if you keep seeing this error. (Please include the request ID 70e925d7-bd56-4ac9-b02b-05648a15d211 in your message.). (code: unknown_error)

It’s working for me but I’m new to this and might not fully understand the question. I am using a vector store and variables for my query and it’s working as expected for me.