IO_node_Script

If you've ever stared at a red, broken node in someone else's workflow and thought "which extension is this even from," IO_node_Script is the kind of node built for exactly that moment. It's not part of a generation pipeline at all - it's a lookup tool that lives inside ComfyUI-Apt_Preset but points at your entire node registry, not just this pack's own nodes.

Here's the tell: the selected_node dropdown on this node lists roughly 1,194 choices in a stock install, which is way more than Apt_Preset ships on its own (that pack has around a hundred). That number is the sum of every node class currently registered in your ComfyUI process - core nodes plus whatever every other custom_node pack you've installed contributes. So this thing is basically a searchable directory of your whole node ecosystem, wearing an Apt_Preset badge because that's the extension that built it.

How you'd actually use it. You type into search to filter the giant list down (handy, because scrolling a dropdown with over a thousand entries by hand is nobody's idea of fun), flip show_all if you want the unfiltered view back, and pick a selected_node from what's left. refresh_list re-scans the registry - useful if you just installed something new and want the node picker to notice it without you having to hunt through menus. One caveat worth knowing up front: ComfyUI generally only picks up brand-new custom nodes after a full restart, not a live refresh, so if a node you just installed still doesn't show up after hitting refresh_list, that's the ComfyUI backend being ComfyUI, not this tool being broken - restart and try again.

The single output is node_source, a STRING. Based on the schema this is meant to hand back where the selected node actually comes from - which module/extension owns it - which is the whole point of a node like this. This pack's own README doesn't document the node in prose (the description field is blank), so treat that behavior as the reasonable read of the inputs and outputs rather than something confirmed line-by-line by the author.

Where this earns its keep. Debugging IMPORT FAILED errors is the obvious case. There's a real thread on r/comfyui where a user hit an IMPORT FAILED specifically on ComfyUI-Apt_Preset itself, triggered by a missing dependency further down the chain (a ShowText node from pythongosssss's Custom-Scripts pack). The fix there was mundane - install the actual missing package via Manager or a manual git clone - but the diagnostic step, figuring out which pack a failing or unfamiliar node belongs to, is precisely what IO_node_Script is for. It's also just handy day-to-day if you download a workflow off Civitai or a Discord and it's full of nodes you don't recognize.

Installing it. Same as every other node in this pack: search "ComfyUI-Apt_Preset" in ComfyUI Manager and install, or do it by hand -

cd ComfyUI/custom_nodes
git clone https://github.com/cardenluo/ComfyUI-Apt_Preset.git

then run install.bat on Windows to pull in the pack's Python dependencies, and restart ComfyUI. No model downloads, no GPU dependency - this node is pure metadata, so it should work the moment the pack imports cleanly.

Troubleshooting. If IO_node_Script itself is missing after install, it's almost certainly the same IMPORT FAILED class of problem the pack has hit before - check your ComfyUI console log on startup for the actual Python traceback rather than guessing, since the real culprit is usually one missing pip package rather than anything wrong with this specific node. And don't expect it to catch nodes from a pack you installed five minutes ago without restarting; refresh_list searches what's already loaded, it doesn't hot-load new extensions.