Ever wonder how transactions get the green light? Think of a policy engine as your blockchain's silent guardian.

Here's the play: you fire off a transaction. Behind the scenes? The engine springs into action—scanning limits, checking permissions, weighing risk factors against preset rules. Every parameter gets scrutinized. Only when everything aligns with the policy framework does your transaction sail through.

It's like having an automated security checkpoint that never sleeps. No human intervention needed, just pure protocol logic making split-second decisions on whether your move is legit or gets blocked.