Recommended but not mandatory
No you do not.
We were there for dinner and zero wait no reservations, you can find a chalkboard with wait times for many of the places along the main walkway at Disney Springs.
We were there for early dinner, no teservstions. We were seated right away on the outside deck.
I walked in for lunch and it was a 10 min wait. But if its a busy day you can call before might be better.
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