Can anyone help me code in the trello 's Buttler?

[Sina Akbar]

Hello fellas,

I am looking for a way to make a simple helpful rule:

If I add a card in a list [For example subjects] I can have a line added to another card's description field [For example Class summary]

So, in the end, I have a card called "Class Summary" which has a description in which I can have a complete list of all the subjects I am going to teach.

[Ludo]

Hi 

By considering that "class summary" card is parent card and the cards added in list subjects are child cards, you can create dependencies between the cards by using this rule

when a card is added to list "subjects", find a card titled "class summary", and add item "{triggercardlink}" to checklist "subjects"

The child cards will be added in the "subjects" checklist of the parent card.

Just make sure that "subjects" checklist is already created in the "class summary" card.

https://help.trello.com/article/1165-task-dependencies