Lora Stack to String

Lora Stack to String [RvTools] takes a LORA_STACK - the list of LoRA entries that rgthree's Power Lora Loader popularized - and converts it into the standard prompt syntax: <lora:name:strength:strength> tokens joined into one string. If you've ever wanted to know exactly which LoRAs a workflow is actually applying, or wanted to bake that info into saved metadata, this is the node.

Why you'd reach for it

LoRA stacks are great for the graph but invisible on disk. A stack is a list of (name, model_strength, clip_strength) tuples inside a single wire - there's no text anywhere that says "this workflow used StyleX at 0.7 and DetailFix at 0.4." When you save an image, write a workflow description, or log what you ran, that's exactly the info you want in text form. This node generates the <lora:...> snippet you'd otherwise hand-type.

The output is also directly usable as a prompt fragment if you're reconstructing a prompt from stack data, or as a metadata field for sharing - "workflow included" culture on CivitAI and Reddit lives and dies on reproducible settings, and a LoRA list in text is reproducible.

How it works

The convert method walks the stack and builds " ".join(f"<lora:{name}:{model_strength}:{clip_strength}>" for each tuple). Each entry becomes one token, entries separated by spaces. Feed it a two-LoRA stack and you get <lora:StyleX:0.7:0.7> <lora:DetailFix:0.4:0.4>.

Input: lora_stack - a LORA_STACK, typically from rgthree's Power Lora Loader or a stack-building node.

Output: LoRA string - one STRING containing the full token list.

Install

Standard RvTools install:

• ComfyUI Manager → search "RvTools" → install ComfyUI-RvTools_v2 → restart.
• Or: cd ComfyUI/custom_nodes && git clone https://github.com/r-vage/ComfyUI-RvTools_v2, then restart.

No models or downloads. You do need the producer of LORA_STACK - usually rgthree-comfy's Power Lora Loader - installed to have anything to feed it, but that's a separate pack.

Gotchas

The one real gotcha: an empty stack produces an empty string, not an error. If your metadata suddenly lacks LoRAs, check the upstream loader actually has entries loaded - a stack with all entries disabled may still be non-empty, but a truly empty stack silently gives you "". Also, the format is A1111-style <lora:...> syntax; if you're feeding this into something that expects ComfyUI's native loader format, it won't match - it's for text output, not for re-loading.

Usual pack caveats: RvTools v2 is unmaintained (successor ComfyUI_Eclipse), and v1-era node names won't auto-map in old saved workflows.