Sleep (Image tunnel)

This is the "must be wired through" version of the sleep node in ComfyUI-LogicUtils: you set an interval, ComfyUI pauses on this node for that long, and then whatever came in on the other socket gets handed straight back out. Despite the display name - "Sleep (Image tunnel)" - and its slug naming it SleepNodeImage, the socket itself isn't actually locked to the IMAGE type; it's typed *, the same wildcard as everything else in this pack. It'll happily tunnel a string, a latent, or anything else you route through it, not just images.

It ships with aria1th's ComfyUI-LogicUtils, a bundle of small logic/math/data-plumbing nodes from the same GitHub account that trained the Illustrious XL checkpoints under the AngelBottomless handle - unrelated work, same person, and this pack has been quiet since a last push on 2026-01-21.

How it works

Two required inputs: interval (how long to pause) and image (the value to tunnel through). ComfyUI executes nodes one at a time within a queued run, so this node blocks that entire run for interval before releasing the value onward. It's not documented in seconds, but that's the standard convention for this kind of delay, so treat it as seconds and test with something small first.

Inputs and outputs

• interval - pause length, default 0.
• image - the value to tunnel through. Despite the name, typed *: anything can pass through here, not strictly IMAGE.
• Output - a single *, the same value that came in on image, delayed.

Where you'd actually use it

The difference from its sibling, SleepNodeAny, is that this one's pass-through value is required rather than optional - you can't leave it dangling, which makes this the version to reach for when you specifically want an inline delay dropped in the middle of an existing chain: image comes out of one node, goes through this one, keeps going into the next, and the only thing that changes is timing. It's a natural fit if something downstream is rate-limited (an external API call, a webhook) and you want a deliberate gap between iterations of a loop, or you just want to slow a graph down enough to watch it execute step by step while debugging.

Installing it

ComfyUI Manager → search ComfyUI-LogicUtils → install → restart. Or:

cd ComfyUI/custom_nodes
git clone https://github.com/aria1th/ComfyUI-LogicUtils

No models to download, and reportedly nothing much to fight dependency-wise - a r/StableDiffusion thread recommending small logic-node packs over heavier alternatives (WAS Node Suite, Impact Pack) pointed at this pack specifically for having no dependencies. The README backs that up: its auto-install hook is opt-in (COMFYUI_LOGICUTILS_AUTO_INSTALL=1) and can be forced off entirely (COMFYUI_LOGICUTILS_SKIP_INSTALL=1).

Common issues

The one thing that trips people up is the name versus the type: if you were expecting this to validate or reject non-image data because it says "Image tunnel," it won't - the socket is a wildcard, and ComfyUI's graph won't stop you from routing a string or a number through it. That's a feature for flexibility, not a bug, but it means the node offers zero type safety despite the label.

The other thing worth knowing generally: this pauses the entire queued run wherever it sits, not just a downstream branch - ComfyUI doesn't execute parallel branches of one prompt concurrently. And like the rest of this pack, it hasn't been updated since January 2026, so treat it as stable-but-unmaintained rather than actively supported.