There are two times you can use agile strikes. 1) Bonus action you give someone a BI die thus expending a use of BI (note the BI die you gave will be expended later, but you expended a us of BI)
2)Reaction you expend a use of BI to do inspiring movement.
That is it. There is no way to expend a use as an action. I’m betting that it probably took an action to get irresistible dance back at some point of the design, but they realized that was too much of an action economy cost and made it no action. That’s just a guess though.
I had this exact same problem when currently playtesting a level 10 Dancebard. Trying to play as written in the UA with expending the die only working on Inspiring Movement lead me to BI hoarding and I never ended up giving out the die to use to party members. Also with the movement I didn't always have a good target to make an unarmed strike against so my amount of Agile Strikes over I think 3 basically back to back encounters was... once? It gave me feels bads though Inspiring Movement itself was great. I think it should work as getting a strike when using a bonus action to give out BI but it is just not clear what the right way to play is, which then makes playtesting hard to give feedback for.
It definitely just needs word clarification on expend and what is expended to activate the trigger
edit: if we do more testing with these characters I play to use with it triggering on giving out BI bonus action and see how that feels to compare
There are two times you can use agile strikes.
1) Bonus action you give someone a BI die thus expending a use of BI (note the BI die you gave will be expended later, but you expended a us of BI)
2)Reaction you expend a use of BI to do inspiring movement.
That is it. There is no way to expend a use as an action. I’m betting that it probably took an action to get irresistible dance back at some point of the design, but they realized that was too much of an action economy cost and made it no action. That’s just a guess though.
I had this exact same problem when currently playtesting a level 10 Dancebard. Trying to play as written in the UA with expending the die only working on Inspiring Movement lead me to BI hoarding and I never ended up giving out the die to use to party members. Also with the movement I didn't always have a good target to make an unarmed strike against so my amount of Agile Strikes over I think 3 basically back to back encounters was... once? It gave me feels bads though Inspiring Movement itself was great. I think it should work as getting a strike when using a bonus action to give out BI but it is just not clear what the right way to play is, which then makes playtesting hard to give feedback for.
It definitely just needs word clarification on expend and what is expended to activate the trigger
edit: if we do more testing with these characters I play to use with it triggering on giving out BI bonus action and see how that feels to compare
It does work when you give out inspiration. You read the feature wrong. Many of us did, myself included.