Load Workflow

LoadWorkflow is the boring, extremely useful glue node that sits at the front of the Alchemine pack's remote-API workflow. It reads an API-format workflow JSON out of ComfyUI/user/default/workflows/ and hands it to you as a plain STRING, ready to feed straight into Api Generate or Api Submit.

If you've ever spent ten minutes squinting at a blob of JSON inside a Save Text node - checking that every brace is balanced so your RunPod job doesn't 400 - this is the node that makes you stop doing that. Keep your workflow in a proper .json file, edit it in a real editor, and LoadWorkflow just serves it up. It's the difference between maintaining a remote-graph setup and fighting it.

How it works

ComfyUI's native "Save (API Format)" button writes exactly the kind of file this node expects - the flat graph of {node_id: {class_type, inputs}} that the /prompt endpoint understands, not the UI-format workflow with all the visual layout data. LoadWorkflow walks ComfyUI/user/default/workflows/ (subfolders included), collects every .json it finds, and exposes them as a dropdown on the filename input. Pick one, and the node returns the file contents verbatim on its text output.

It's intentionally dumb, and that's the point. The IS_CHANGED method is keyed to the file's modification time, so ComfyUI re-runs the node (and re-pushes the workflow) when you save the file on disk - edit the JSON, re-queue, done. No copy-paste step in the middle.

Inputs and output

The one input is filename, a dropdown of every workflow JSON in your workflows folder. You can't type it; it's populated dynamically from disk, which means it only appears after the pack loads.

The single output, text, is a STRING - the raw file contents. Wire it into the workflow socket of Api Generate or Api Submit and you're done. Both of those accept either this output or a path string, but feeding the actual contents means you can also pipe it through something like Evaluate first if you want to tweak it before it ships off.

Install

This is part of the ComfyUI-Alchemine-Pack, so it installs with the whole pack:

cd ComfyUI/custom_nodes
git clone https://github.com/alchemine/comfyui-alchemine-pack
pip install -r requirements.txt

Or just search "ComfyUI-Alchemine-Pack" in ComfyUI Manager and click install. The pack's only hard dependency is python-dotenv; there are no model downloads, which is why it's such a cheap node to add.

Common issues

The classic gotcha is saving a workflow in UI format instead of API format. The node will happily load it and Api Generate will fail with an error about missing nodes or classes, because the JSON structure is completely different. The menu path is "Workflow → Save (API Format)", not the normal save. If the file doesn't show up in the dropdown at all, it's not ending in .json or it's outside user/default/workflows/.

The other mild trap: subfolder paths show up in the dropdown with / separators. If ComfyUI regenerates its user/default directory after an upgrade, your saved workflows go with it - keep a copy somewhere safe.