Aspects & Fate Points
Aspects are short true phrases — about your character, the scene, or the whole campaign. If it's an aspect, it's true, and truth has mechanical weight. The full chapter is @Missing file; the economy chapter is @Missing file.
Invoking
When an aspect would genuinely help your roll, invoke it: explain how, pay 1 fate point, and take your pick — +2 to the roll, a reroll, +2 to an ally's relevant roll, or +2 opposition against an enemy. Each aspect backs a given roll once, but different aspects stack: on the big roll, a prepared character cashes in the scene they spent three exchanges building.
Free invokes are the discount version: creating an advantage (or succeeding with style) sticks one or more free invokes on the aspect — spend those without paying a fate point. They're tracked right on the aspect's freeInvokes field.
Compels
The other edge: when one of your aspects could complicate the scene, the GM offers a compel — because you have @Missing file*, it makes sense that the Tidewatch sergeant recognizes you.* Accept, and the complication happens and you gain a fate point. Refuse, and you pay one. You can also propose compels on yourself — walking into trouble your aspects demand is how you bankroll the endgame. At zero fate points you can't refuse, so don't hoard your trouble; sell it early, when the price of the complication is still one you can afford.
Refresh
Your fate points reset to your Refresh (normally 3) at the start of each session — unless you ended the last one higher, in which case you keep the surplus. The rhythm of play is the rhythm of this economy: earn by being compelled, spend to win the moments that matter. Situation aspects like @Missing file belong to everyone — invoke the world's fog against the Tidewatch, and remember the Tidewatch can invoke it right back.