Help with States tool in Dev tools

trying to change a zwave node state from is_failed: false to is_failed_true. The docs are not at all clear on how to do this. Once I select the entity in the drop down i then have to populate one of two fields (State, State Attributes) or perhaps both. I’ve tried every combination I can think of as follows:

“is_failed”: true
“is_failed”:“true”
{“is_failed”:“true”}

I’ve tried these entries in either of the two fields and I can’t get the state to change. What am I doing wrong?

what zwave node is this?
and what is the is_failed item?? I’m assuming an attribute, and if I’m correct you’ll have to provide the state AND all attributes if you don’t want to lose them. If you only provide the one attribute (is_failed) that’s all you’ll see…