Can you react to your own Jinx, Loose Cannon legend trigger, and do you get priority first?

Ruling: Yes, you can react to your own Jinx trigger. As the controller of the trigger, you have the first priority to play reactions to the chain.

Nuances:

• Jinx's ability triggers every turn at the start of your beginning phase, regardless of your hand size
• The "if you have one or fewer cards in hand" is part of the effect, not the trigger condition
• Opponents can also react to the trigger
• The trigger condition is "at the start of your beginning phase" - everything after the comma is the effect