Mie Loop State Set String 🐑

Set String is the write half of the text pair in MieNodes' Loop State family, matched with Get String. Anywhere a for-loop needs a piece of text to survive from one pass to the next - an evolving prompt, an LLM's running critique, a log of what each iteration did - this is the node that actually commits the string somewhere it'll still be there next lap.

How it works. Loop state travels as a custom object, MIE_LOOP_CTX, that flows through the loop and gets rewritten pass by pass. Set String takes the current context, a key, and a value string, stores it under that key, and returns the updated context to carry forward - the rest of this pass, and the loop's next iteration, both read from that updated object.

Default key feedback_string matches the naming across the family and hints at the intended pattern: a loop where each pass generates some kind of feedback in text form - an LLM judge's reasoning, a running caption, an accumulated note - that shapes the next pass.

What's on the node.

• loop_ctx (required) - must come from another Loop-category node in this pack.
• key (default feedback_string) - has to match what the corresponding Get String node reads.
• value (default empty string) - the text you're writing. This node overwrites whatever was previously stored, it doesn't append.

Output: the updated loop_ctx.

Installing. Manager: search ComfyUI_MieNodes, install. Manual: cd ComfyUI/custom_nodes && git clone https://github.com/MieMieeeee/ComfyUI-MieNodes, then restart ComfyUI. No models, no extra dependencies - plain text bookkeeping.

The usual caveat for this family applies: the README has no coverage of the Loop category at all. This description is built from the node's schema and from how a text-carrying loop has to be wired, not from confirmed pack documentation.

Troubleshooting.

• Text isn't accumulating - every pass just replaces the last one. That's the actual, expected behavior of this node: it overwrites. If you want text to build up across iterations (a running log, an appended history), read the existing value with Get String first, concatenate your new text onto it with a string-join node, and feed the combined result into value here.
• Downstream Get String still returns default_value. Check the key strings match exactly between this node and whatever's reading it - free-text fields, case-sensitive, no error on mismatch.
• String output looks cut short after a few loop passes. If the text is coming from an LLM call each iteration, check that connector node's max-token setting isn't clipping the response before it ever reaches this node - that's happening upstream, not here.
• loop_ctx type error. Something other than another Loop-category node's context output from this same pack is wired into that socket.