Ino Cast String To Combo

Dropdown inputs in ComfyUI - the "combo" type - are a quiet source of pain. They're great for picking from a fixed list by hand, but they famously refuse to accept a string wired in from another node, even when the value you're sending is one of the valid options. Ino Cast String To Combo exists for exactly that fight. It takes a string and outputs it typed as a combo, so the wire finally docks.

The node's own description is the best summary: "Convert a string to a combo-compatible output. Wire this into any combo input (e.g. parent_folder)." The Ino pack's file nodes are the canonical example - their parent_folder dropdown (input/output/temp) is a combo, and if you're building an automated pipeline where the folder gets chosen programmatically, you can't just drag a string onto it. This node makes that connection legal.

How it works

It's a pass-through with a type change: input_string comes in, the same string goes out, now declared as * (any) which a combo input will accept. There's no validation - if you feed it "nonexistent_folder" and wire it into a parent_folder combo, the node won't stop you. The downstream node either accepts the value at runtime or fails with a clear-enough error. That's the trade-off for the flexibility.

Worth saying plainly: this is a workaround for a ComfyUI quirk, not a feature you'll build a workflow around. When ComfyUI lets you wire strings into combos natively (or the node author changes the input type), this node's reason to exist evaporates. Until then, it's the right tool for the specific job.

Inputs and outputs

• input_string (STRING) - the value you want to feed into a combo input.
• combo (*) - the same value, typed so combo inputs accept it.

Installing it

Part of ComfyUI-InoNodes (Inoland). ComfyUI Manager → search "ComfyUI Ino Nodes" → install → restart. Manual:

cd ComfyUI/custom_nodes
git clone https://github.com/nobandegani/comfyui_ino_nodes
cd comfyui_ino_nodes
pip install -r requirements.txt

Restart after. Requires inopyutils (auto-installed) and a current ComfyUI; no keys or downloads.

Common issues

The main gotcha is semantic, not mechanical: the wire will connect, but the value has to be one the downstream node actually recognizes. Wiring "temp" into a parent_folder combo is fine; wiring "tmp" is a silent runtime failure. Double-check the exact option spelling against the combo's list - a mismatch is the #1 way people report this node "not working" when it's actually working exactly as designed, passing through exactly what you gave it.