DebugPrint 🦾

Every ComfyUI user eventually stares at a workflow that should work and asks "what is actually coming out of that node?" DebugPrint answers it: you wire anything into it and it prints the value to the terminal running ComfyUI. No output socket, no preview, no ceremony - just a look inside the wire.

It's the debugging primitive from the original ComfyUI-Logic extension, carried into this pack. If you've spent time on r/comfyui debugging threads, this is the tool people mean when they say "just print it."

How it works

ANY is an any-typed input (declared with a default of an empty dict, which is why the schema lists it as {}). On execution the node calls print(ANY) - printing the raw Python object to the console - and returns nothing. That's the entire mechanism, and its virtue is exactly that there's nothing to get wrong.

The output of the print depends on what you feed it. A string prints as a string. A tensor prints its shape and dtype, which is usually the actual thing you wanted to check. A dict (like the config output of a Compositor Config node) prints its keys and values. It's not pretty - it's raw - but it's honest.

This is an output node, so the print happens every time the upstream value changes. Toss it on a wire you're unsure about, run once, read the terminal.

The inputs that matter

• ANY (required, any type) - whatever you're inspecting.

There are no outputs. That's the point - it terminates the branch it sits on, so put it on a reroute or a duplicate, not in the middle of a chain you need to continue.

Install

Ships in ComfyUI-Beyond_nodes. ComfyUI Manager → search "Beyond_nodes" → install → restart. Manual:

cd ComfyUI/custom_nodes
git clone https://github.com/beyondprompting/ComfyUI-Beyond_nodes

Restart. No dependencies beyond core ComfyUI.

Common issues

• I don't see anything printed. Check the terminal/console where you launched ComfyUI, not the browser. That's where print lands.
• It prints, but I can't make sense of it. For tensors you're usually fine with shape/dtype. For real "what does this value mean" debugging on strings and numbers, it's perfect. For giant objects, brace yourself - it dumps everything.
• The workflow hangs on it. It doesn't block; if the graph looks stuck, the issue is upstream. The print is synchronous but trivial.

This is the node you add when you're done guessing. Five seconds to insert, one run to learn the truth, and then you delete it - unless you're the type who likes keeping a few around as documentation of what your graph does.