prompt - random

Prompt variation is where a lot of ComfyUI batching lives: one subject pool, one template, N outputs to pick from. prompt - random from the ymc suite is a compact take on that - you give it a list of choices and a template, and it emits a list of prompt strings (up to 1000 of them) that you can loop through or sample.

It's adapted from the mixlab nodes family, and the default content is telling: a playground full of playground equipment. The mechanism is what matters, not the example.

How it works

The node does a Cartesian product between two multi-line inputs:

• mutable_prompt - the pool. One option per line (Swing, Slide, Climbing frame, …).
• immutable_prompt - the template. One template per line, and `` (double backtick) is the hole where each mutable option gets dropped in.

So with a template of sticker, Cartoon, `` and a pool of 30 playground items, you get sticker, Cartoon, Swing, sticker, Cartoon, Slide, and so on - 30 prompts. max_count caps the list length. With random_sample set to enable, it picks a random sample of that many from the full product; with disable, it takes the first max_count in order. The optional seed input (an "any" type, so it can be wired from a seed source) makes the random pick reproducible.

Because the output is a list (STRING list), you pair it with anything that consumes a list of prompts - a loop over prompts, or a batch that encodes each one. One node becomes a mini A/B test rig: 30 variations, generated in one queue.

Inputs and outputs

The three that matter:

• mutable_prompt - your pool of choices, one per line
• immutable_prompt - the template, `` as the placeholder
• max_count - how many results to emit (1–1000, default 9)

Plus random_sample (enable/disable) and the optional seed. Output is one STRING list. It also shows the generated prompts in its UI preview.

Installing it

Part of ymc-node-suite-comfyui:

• ComfyUI Manager → search ymc-node-suite-comfyui → Install → restart, or

cd ComfyUI/custom_nodes
git clone https://github.com/YMC-GitHub/ymc-node-suite-comfyui

restart, and pip install -r requirements.txt on a manual clone (four yors_* helper libs; auto-install is commented out). No models, no GPU.

Search prompt / random on the canvas or use the right-click ymc suite menu.

Common issues

• "It only returned one line of my template." The `` placeholder is required for substitution - if your template line has no ``, the whole immutable line is used as-is and combined with every pool item (the node appends , `` if it's missing, so mostly this "just works"). Empty pool lines are skipped.
• max_count is a ceiling, not a guarantee. If the product has fewer combos, you get fewer results.
• The seed only matters when random_sample is enable. In disable mode the first N are taken deterministically regardless of seed.
• WAS Node Suite conflicts on the pack's io/save nodes can appear if you run both packs - unrelated, but a common post-install warning.

If you want variation within a single prompt instead - same tags, different order - the pack's prompt - shuffle does that with a seed and keeps a chosen prefix fixed.