How to add a custom tool in this flow?

[remixdance]

Hi This is my flow i have a Conversation chain with a prompt but I want to expand the funcionality adding a custom tool but I cant find the right way to do that. The reason is because i want to "save" the answers or some variables that the bot tells me about some Images I upload and save it on a database using an API of the database

[remixdance]

I found this way;

but for some reason each time I uploaded the images on the agent they told me that I need attach the images again

[remixdance]

This is my flow
Test3 Chatflow.json