🔄 Dynamic Value Generator

This node does one tiny thing: it generates a string that changes every time the workflow runs. A timestamp, an incrementing counter, a short UUID, a random number, or a custom value. It's the kind of "utility" node that looks pointless until you understand why it exists - it's the refresh trigger for the pack's HTML Previewer.

Remember that ComfyUI only re-runs a node when its inputs actually change. If your preview page is built from static content, the HTML Previewer has no reason to rebuild it - the URL stays the same, so the panel shows stale results. But if you append a changing value to that URL via auto_refresh_token, the preview reloads on every queue. That's precisely what the Dynamic Value Generator produces.

How it works

Pick a value_type and it hands back a dynamic_value string:

• timestamp - current date/time formatted with format_string (default %Y%m%d_%H%M%S, standard strftime). The workhorse choice for refresh tokens; every run differs.
• counter - increments by one each run, starting from counter_start (default 1). Also changes every run, and it reads nicely if you're logging "generation #7".
• uuid - an 8-character slice of a UUID. Unique every time, no state involved.
• random - a random number between 1000 and 9999.
• custom - a unix timestamp, useful when you want a big stable-ish number.

custom_prefix (optional) prepends any text - handy for making tokens readable, e.g. job_20260816_114523.

How you'd actually use it

The intended loop is dead simple:

DynamicValueGenerator → dynamic_value → HTMLPreviewer.auto_refresh_token

Feed the output into the HTML Previewer's refresh-token input and your preview panel updates every run, no manual reloading. You can also drop it into a Text Template node ({{value1}} and friends) to stamp generated content with a timestamp, or use it to build unique filenames and IDs elsewhere in the graph. The pack's html_previewer_workflow.json and hitem3d_history_workflow.json examples show it wired up.

Installing

Same pack as everything else - ComfyUI Manager (search "ComfyUI HiTem3D Integration") or:

cd ComfyUI/custom_nodes
git clone https://github.com/GeekatplayStudio/comfyui-hitem3d
cd comfyui-hitem3d
pip install -r requirements.txt

Restart ComfyUI. Nothing to download, no API keys needed - this node is pure local utility and works even if you never configure a HiTem3D account.

Where people get burned

• "My preview never refreshes." If the token isn't actually changing, the preview won't either. Make sure you're feeding this node's output into auto_refresh_token, and that value_type isn't set to something static.
• Counter quirks. The counter lives on the node instance for the session, so it resets when ComfyUI restarts - and it behaves a little differently on first run versus later ones. For a pure "always changes" token, timestamp or uuid is more predictable.
• It's a string. Everything it outputs is text. That's the feature, but it's worth remembering when you wire it somewhere expecting a number.

It's a four-line tool doing a four-line job - but as the heartbeat for auto-refreshing previews, it's the difference between a dashboard that updates itself and a stale tab you have to babysit.