Error when retrieving data with "Vector Store Question Answer Tool" node using AI Agent

[kienpro-dev]

Bug Description

I'm currently using the AI Agent (Conversation Agent) node in a workflow where the agent is utilizing the Qdrant Vector Store Tool to retrieve information from a venue. The Vector Store Tool is attached to the Mistral model (small lastest). The embedding model in use is Mistral, and while it works intermittently, I frequently encounter an error with the message:

"Cannot read properties of undefined (reading 'replace')"

I checked the vector store input response but it seems that the "query" field is missing and the "k" (limit) field is still there.

To Reproduce

1 - Add a Qdrant Vector Store Tool node to the workflow, connected to the Mistral model (small lastest)
2 - Set up the Vector Store Tool to retrieve embeddings from Qdrant, using the Mistral embedding model.
3 - Query the AI Agent node to retrieve information.
4 - Observe that the workflow sometimes returns the error: Cannot read properties of undefined (reading 'replace').
5 - Missing "query" field in vector store input response.
6 - Run the chat again. The issue temporarily resolves but reoccurs after some time.

Expected behavior

The AI Agent should consistently query the vector store tool without any issues, while this happens intermittently, I can't see the reason why.

Operating System

Docker run on Centos 8

n8n Version

1.81.4

Node.js Version

= 20.15

Database

SQLite (default)

Execution mode

main (default)

[Joffcom]

Hey @kienpro-dev,

We have created an internal ticket to look into this which we will be tracking as "GHC-1295"

[Joffcom]

Hey @kienpro-dev,

Can you try updating n8n to 1.84 and using the new agent node as the conversational agent is now deprecated in favour of just a tools agent which can do the same thing and often a lot better.