ComfyOnlineSaveFile

Let's be straight about this one: it's one of the least-documented nodes in the pack, and I'd rather tell you exactly what's knowable than pad it out with guesses. Its own schema lists a single required input - file_path, a plain string - and no output. That's it. No image, audio, or file-data socket to actually feed it something to save; just a path.

What it's most likely for

The node lives in the comfyonline-dynamic category alongside ComfyOnlineUploadAnything, and the pack as a whole is built, by its own README, "for comfyonline dynamic loader" - plumbing for ComfyOnline (comfyonline.app), a paid ComfyUI cloud service, rather than a general-purpose node meant to stand alone in any workflow. The most plausible read is that it hooks into something ComfyOnline's own executor tracks behind the scenes - telling that platform's backend where an output file has landed, or marking a path as the thing to collect and hand back through their API - rather than taking file contents as a normal ComfyUI socket input the way SaveImage or SaveAudioAsWav do.

That's an inference from the shape of the schema and the pack's stated purpose, not something confirmed in the README, which says nothing about this node specifically. If you're trying to use it and it isn't behaving the way a "save" node normally would - receiving data and writing it - that's likely why: it's designed around a specific host's own file-tracking mechanism, not around being fed something directly.

The input that matters

• file_path (STRING, required) - the node's own tooltip is just "filename." No default value, no further explanation of what format it expects (absolute path, relative to an output directory, a filename with no path at all) or what happens to whatever's at that location.

is_output_node is true, meaning ComfyUI treats it as a graph endpoint the same way it treats SaveImage or SaveAudioAsWav - something the execution runs to, not through - but with no data socket, the "what does it do at that endpoint" part is the part that isn't documented.

How to install it

• ComfyUI Manager - search "comfyui-model-dynamic-loader," install, restart.
• Manual - cd ComfyUI/custom_nodes && git clone https://github.com/jax-explorer/comfyui-model-dynamic-loader, then restart.

No dependencies listed for this node specifically, and nothing about it suggests it downloads anything - the rest of the pack's install notes (no bundled models, fetches happen elsewhere at run time for the loader nodes) apply the same way here.

Common issues & troubleshooting

It runs but doesn't seem to write anything you can find. Given the schema takes no file content as input, that may simply be expected behavior outside of ComfyOnline's own hosted environment - there's nothing here for it to save from in the conventional sense. If you actually want to write image or audio data to disk from a workflow, SaveImage (core ComfyUI) or SaveAudioAsWav (elsewhere in this same pack) are the nodes built for that.

You're running this on comfy.icu or another host and expecting ComfyOnline-specific behavior. It's reasonable to expect this node is scoped to ComfyOnline's own infrastructure rather than portable across any ComfyUI host - the pack's own framing supports that reading, even though it isn't spelled out node-by-node.

If you find yourself needing this node specifically and it isn't doing what you expect, the most useful next step is checking the pack's GitHub repository directly (jax-explorer/comfyui-model-dynamic-loader) for the source of this node - the README alone doesn't cover it.