SaveMetaData (Mikey)

ComfyUI already embeds your full workflow into a saved PNG's metadata - but that's only useful if you're opening the image back in ComfyUI to read it, and it doesn't give you a plain, greppable record you can skim without loading an image editor at all. SaveMetaData's job, per the README, is narrower and more direct: pick up whatever's in the prompt and extra_pnginfo data at the point this node runs, and write it out to a plain .txt file alongside your output.

How it works

Wire an image through this node the same way you would a Save Image node, and it captures the current run's prompt and extra metadata into a text file, named using whatever combination of prefix, timestamp, and counter you've configured. It's a companion to your actual image-saving step, not a replacement for one - this node has no image output and is flagged as a terminal output node in its own right, meaning it can sit at the end of a branch on its own, but you'll still want a normal Save Image node elsewhere in the graph to actually get the picture.

The inputs and outputs that matter

• image - required, even though nothing about this node's job needs pixel data. It's there to establish execution order - the node runs (and captures metadata) at the point in the graph where this image exists, not before.
• filename_prefix (STRING, default empty) - text prepended to the saved file's name. Leave it blank and you're relying entirely on timestamp_prefix and counter to keep filenames distinct.
• timestamp_prefix (default true) - prepend a datestamp to the filename, matching the pattern the README describes for the pack's related Save Image With Prompt Data node (datestamp, then part of the prompt).
• counter (default true) - append an incrementing counter so repeated runs with the same prefix and timestamp don't collide or overwrite each other.
• No outputs - this node is a sink. Its whole job is the side effect of writing the file.

How to install it

Bundled with the rest of Mikey Nodes. ComfyUI Manager: search "Mikey Nodes," install, restart. Manually:

cd ComfyUI/custom_nodes
git clone https://github.com/bash-j/mikey_nodes

then restart. No models, no extra dependencies - it's just file writing.

Common issues & troubleshooting

No file showing up. Since image only exists to sequence execution, make sure this node is actually connected into a branch that runs - an orphaned node with nothing feeding its image input, or one ComfyUI decides doesn't need to execute because nothing downstream consumes its (nonexistent) output, may get skipped. Wire it off a branch you already know executes, like right after your Save Image node.

Filenames colliding or overwriting each other. Turn counter on if it isn't already - with both timestamp_prefix and counter off and an empty filename_prefix, you have nothing distinguishing one run's text file from the next.

Can't find where the file was written. The README doesn't spell out the exact output path for this node; if it's not appearing where you expect, check your ComfyUI output directory first - text-writing nodes in this ecosystem typically land there by default, same as saved images.

On a hosted or serverless ComfyUI, the text file may not be easy to retrieve. Writing to local disk works differently once you're not running ComfyUI on your own machine - on a service like comfy.icu, check how outputs are surfaced back to you (typically alongside your generated images) rather than assuming you can browse the container's filesystem directly afterward.