What exactly does Agility do?

I've heard a couple of things, boost duration, rate of fire, initial firing time, boost startup time. Would the attack speed increase from zero system benefit from agility?

I've placed around 4-5 points with my GM Command into Agility / Reaction.
And I can tell you this: It's my favorite stat.

But how does it work?
Imagine Amuro at the start of the one year war. And then in the final fight where he performs outrageous manouvers.
That's kinda how Aglity works.

what agi does is it increase reaction time of the unit, or decrease the lag of motion. So the motion to pick up the gun and fire would be faster. More like a quick draw. For melee units, u can draw ur sword faster than ur enemy. Meaning u will get the first hit even though both u you press atk at the same time. Its more apparent for units that has stun beams. Both of you click stun beam at the same time, but the person with greater agility will fire first, leaving the other stunned. Works great with units with zero system and limit release, godly atk speed.