Ⓜ️ Debug Viewer

Ever wired a pipe node into something, hit run, and gotten expected X, got Y from a node three steps down the line? The Mithril Debug Viewer is the stethoscope for that moment. It takes any data type - that * input really does accept everything - and prints the thing out as readable, indented JSON so you can finally see what's actually traveling down your wire instead of guessing.

It lives in MithrilNodes, a small, young pack (still 0.1.0, a single commit at the time of writing) with zero community footprint, so temper your expectations: this isn't rgthree's Display Any with years of polish behind it. It's a simple, honest debug node, and for that job it works fine.

How it works

Drop it on a side branch off whatever you're curious about and connect its data input. On execution it recursively serializes the object - dicts and lists get walked, torch tensors get flattened via .tolist(), and anything it can't classify falls back to its repr(). Three knobs control the output:

• show_on_console (default on): prints the dump to the terminal where you launched ComfyUI, prefixed with the node's display name.
• show_on_display (default on): pushes the same text into a UI popup so you see it in the browser.
• max_depth (default 3, 0–10): how deep it recurses into nested structures before giving up and writing MAX DEPTH (3) REACHED.

Both toggles default to true, which is the one way this node will surprise you: if you only wanted the console dump, you still get a popup, and vice versa. That's the first thing to check when the output lands somewhere you weren't looking.

Where people get burned

• Don't feed it a raw latent. A 4×H×W latent tensor converts to a list of every single value - that's a million numbers dumped into your terminal. It won't crash, but you'll scroll for a while. Keep max_depth low or feed it small things: strings, dicts, config objects.
• It's a terminal node. is_output_node is set and it returns nothing, so you can't chain anything off it. Put it on a parallel branch off the wire you're inspecting, not inline, or you'll have to rewire the graph to look at it.
• A shallow max_depth hides everything. At 0, any dict/list hits the depth sentinel immediately. If your structure looks empty, bump it before assuming the data's broken.

Install

It ships in MithrilNodes, so you get all seven nodes at once:

• ComfyUI Manager: Manager → Install Custom Nodes → search Mithril (the pack title is "Mithril-Nodes for ComfyUI") → install → restart.
• Manual:

cd ComfyUI/custom_nodes
git clone https://github.com/MithrilMan/ComfyUI-MithrilNodes

Then restart ComfyUI. There's no requirements.txt, no model downloads, no hidden dependencies - it's pure Python plus a small frontend, which is more than most debugging tools can say.

One heads-up: the README is a placeholder that still describes a different, "Named Configs" feature set that doesn't exist yet. Trust the nodes in front of you, not the doc.