⚗ Alchemica Save Image (drive + folder + workflow name)

Core Save Image gives you ComfyUI_00042_.png in one folder forever, and a filename prefix field that makes you type a path. This node fixes both: a drive menu, a folder browser, and a filename that defaults to the name of the workflow you're running.

What it is

AlchemicaSaveImagePath is the current save node in ComfyUI-AlchemicaSampler - "⚗ Alchemica Save Image (drive + folder + workflow name)". It replaced the pack's earlier folder-dropdown savers, whose menu was built from the subfolders of ComfyUI's output directory and "looked random" once that directory had any history in it.

You'd reach for it if your outputs currently pile into one folder, if you want a run's images to land next to the client's other files, or if you've ever come back to a folder of ComfyUI_0192_.png and had no idea which workflow made any of them. The filename defaults to the workflow's name, which quietly solves the last one.

The inputs

• images - what you're saving.
• drive - (ComfyUI output) or a real drive. On Windows the menu lists the letters that exist (C:\, D:\…, skipping A: and B:); everywhere else you get /. It's built when the server starts, so a newly mounted drive needs a restart before it shows up.
• folder - a string, and there's a 📁 Browse folders… button next to it for picking one: navigate, create a subfolder, "Use this folder". It's read as relative to the chosen drive, but an absolute path works too, and the folder is created at save time if it doesn't exist. Empty means the drive root itself.
• filename_prefix - defaults to %workflow%. %date% gives you the date, %time% the current time. Files come out prefix_00001_.png, prefix_00002_.png, and the counter continues from what's already in the folder rather than restarting at 1 each run. Name characters that a filesystem won't accept get replaced with underscores.

One thing that trips people coming from core Save Image: this node implements its own %...% tokens, so don't expect ComfyUI's %date:yyyy-MM-dd%-style syntax to work here. %date% and %time% are what's supported.

Outputs and behaviour

It returns saved_path (STRING) - the full path it wrote, which is the useful bit for logging or for feeding a downstream node. The node also shows the path of every saved file on the canvas, and prints it to the console.

Files saved inside ComfyUI's output folder are registered normally, so they show up in the node's gallery view. Files saved outside it get a temporary preview copy instead, because the front end can only serve images it knows about - that's expected, not a failure.

Metadata is the same as core Save Image: the prompt and workflow chunks go into the PNG, so the file drags back onto the canvas and rebuilds the graph. If you're on a ComfyUI started with --disable-metadata, none of that is written and the file is just pixels.

Validation is deliberately always-true here. A workflow saved with a drive that's currently unplugged still queues - the node complains at run time instead of blocking the graph.

Installing it

ComfyUI Manager, search "AlchemicaSampler", or:

cd ComfyUI/custom_nodes
git clone https://github.com/Nessuno76/ComfyUI-AlchemicaSampler
# restart the ComfyUI server

No extra Python packages - the folder browser is a small route the pack registers on ComfyUI's own server, so it works on a local instance. ComfyUI 0.36.0+ is the pack's requirement; a save node won't be what breaks it.

Where it goes wrong

• "the drive X: is not available". The drive saved in the workflow isn't mounted any more. Pick another one from the menu.
• %workflow% produced "immagine". You queued through the API or the node had no interface name to read - the token is filled in by the front-end script, and falls back to immagine otherwise.
• A new folder isn't in the browse dialog. The route reads the filesystem live, but a brand-new drive isn't in the menu until the server restarts.
• You wanted A1111-style metadata for CivitAI auto-linking. Not here. This writes ComfyUI's graph chunks like the core node; if you need the flat parameters block, that's a different save node.
• The preview was taken away. Files outside ComfyUI's output folder are served from a temporary copy in temp/. The real PNG is where you put it; the preview isn't permanent.