Text Template Combiner (Buff)

Most ComfyUI users discover the hard way that you can't just write a {subject} in {style} in a text box and expect the braces to do anything. TextTemplateCombiner is the node that makes that template syntax real: you type a template into main with {1}, {2}, … placeholders, connect strings to matching sockets, and get a single assembled string out. It's prompt assembly without concatenation nodes or a pile of string + string plumbing.

This is one of the most genuinely useful ideas in the pack. Keep the skeleton of a prompt in main - say masterpiece, {1} riding a {2}, dramatic lighting - then connect a subject node and a style node to text_1 and text_2. Swap the subject or style upstream and the whole template re-composes. It's the difference between editing a prompt by hand in six places and editing it in one.

How it works

The node scans main for {N} placeholders and replaces each with the corresponding text_N socket's value. Placeholders also drive the UI: drop a {4} in the template and the node's frontend extension auto-expands to show a text_4 socket - no manual counting. Set inputcount manually if you want more inputs than the template implies, then hit the "Update" action the node exposes.

Two details make it more than a string replacer. First, all 20 text_N inputs exist on the backend regardless of what the browser shows, so raw Prompt API workflows can connect text_9 without the UI extension being involved - the API-safe design shows up all over this pack. Second, there's a random-choice syntax: {foo|bar} in main picks one of the options at random each run, and if an option is a bare number it resolves to that text_N input instead. When a template contains any {a|b} choice, the node uses the float("NaN") IS_CHANGED trick to force re-execution every run so the roll actually changes (the mechanics of that trick are covered in comfyui-node-plumbing.md).

Inputs and output

• main - the template. {1}…{20} for wired inputs, {a|b} for random picks.
• inputcount - how many text sockets to show.
• text_1 … text_20 - the strings that fill the slots (empty by default; placeholders with no connected value resolve to empty).

One output: text, the assembled string. Straight into a CLIP Text Encode or anywhere else a prompt goes.

Install

From BuffMcBigHuge's pack - ComfyUI Manager (search "ComfyUI-Buff-Nodes") or:

cd ComfyUI/custom_nodes
git clone https://github.com/BuffMcBigHuge/ComfyUI-Buff-Nodes

Restart ComfyUI. No extra dependencies.

Gotchas

Empty sockets resolve to empty strings, so a placeholder you forgot to wire just vanishes from the output - check your wires before you wonder why a prompt is missing a word. Placeholders are matched as bare {N}; if your template legitimately needs literal braces, that's a corner this node doesn't really accommodate. And the random {a|b} syntax is easy to read as standard wildcard syntax and be surprised it's always random - by design. For slot-fillable prompts that stay readable, it's a genuinely nice small node.