A very poor document. In the loop, setting a loop variable keeps prompting that the variable is undefined. Please select an existing variable!

[wuyoujushi]

Page URL

https://docs.dify.ai/zh/self-host/use-dify/nodes/loop

Issue type

Missing documentation

Product

Dify Cloud

Dify version

No response

Page language

None

What's wrong

A very poor document.！

What it should say

No response

Checklist

• I have searched existing issues, including closed ones.
• I confirm that I am using English to submit this report. 【中文用户 & Non-English users】请使用英语提交，否则会被关闭。
• If I open a PR for this, it will follow the contributing guidelines (all three languages in the same PR).

[RiskeyL]

@wuyoujushi Thanks for the report, and sorry the page left you stuck. The page is already on our list for optimization, and loop variable configuration will be covered end to end there.

One thing to separate out: "Invalid variable. Please select an existing variable." is a validation message from the workflow editor, not something the documentation controls. If the variable you pick does exist and the editor still rejects it, please open an issue at https://github.com/langgenius/dify/issues with a screenshot of the Loop node panel or your exported DSL, so the engineering team can reproduce it.

Thanks again for taking the time to file this.