Describe the problem/error/question I am finding regularly if an AI Agent gets an error while using a tool, if the problem is with what it is sending to the tool, you never see the input data. Input data to the tool only seems to show in the log after it runs without an error - which makes troubles…

This is a frustrating limitation with AI Agent tool execution logging. When a tool errors out before completing, n8n often does not capture the input parameters the agent attempted to send, only the error response. Your best workaround is adding a manual logging step inside the tool itself. Use a S…

How can i use a set node in the flow? Or would i have to make it a sub workflow and overcomplicate things to do that?

Ahh Thanks, but i dont have any issues sending items tot he AI agent. The problem is the AI agent sending the FROMAI items to a tool it has access to. Like this, its when the ai calls a tool and sometimes it will send invalid data to the tool requirements, but cause I cannot see the input, I canno…

Here’s an example of one of my chat agents, pulled from the same example I used above. In this case, I’m evoking Tavily, for Internet pulls. Here’s what I would do: Set the workflow to inactive, and trigger the workflow, give it an input that would call the tool. In my case, I asked it for tomor…

I wanted to include one more snippet. My original request was: “Why [sp] is tomorrow’s weather forecast for Flint, MI”. Notice that what the AI asked the Tool was: “query”: “tomorrow’s weather forecast for Flint, MI”, [image]

Thanks for the extra detail, can you try this. Put an extra character to break the json going into Tavily. Like in the tool add some random things so it is not a valid json to send to it. So the tool gives an error response and not a success one. then you will see what I mean. If it was a direct …

I wasn’t able to inject extra characters into the JSON and get it to run without an obvious “error found in…” message. But what I WAS able to do was use the Call N8N Workflow Tool, and send the data to that. The first node I used was a NoOp node which showed me the input string. This will at leas…

AI Agent tool error - does not show input

Questions

Robert_Spears December 3, 2025, 8:50pm 4

Here is a workflow example of how I use a set node to normalize the input to the AI Agent.

Hope this helps.

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AI Agent tool error - does not show input

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