Hi @ashafizullah , my apologies, missed this one.
I can be wrong but I do not think AI agent is able to bypass binary files to its tools.
There is also no way to refer to an earlier node as Gmail node expects a field name as a literal.
I’d suggest using the Structured Output Parser tool to get data from the AI Agent and wire Merge and Gmail nodes after an AI node where you’d be able to attach a binary.
Below is a wireframe of what you’d be looking for. I didn’t tune any nodes for your use case. It is just to give an idea of what a workaround would be.