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Advice

Things learned building the examples, in no particular order.

Call MoveTo every tick​

A chase state should call agent:MoveTo(agent.Blackboard.SeenPosition) in Update, every tick. The Navigator decides when that turns into a plan; you do not. Calling it once in Enter works for a fixed point, and the navigator still retries if the mover gets stuck, but a moving target needs the fresh position.

Plan only when it is not obvious​

A chase that plans every step is always a little behind: each plan is a query, and the navigator only re-plans on its cadence. Builder:UseDirect with a Straight walks straight at a target in a clear line and refreshes that line as the target moves; the navmesh is asked only when the line is blocked, and again whenever walking straight stops making progress for DirectStuckTime. agent.Navigator:IsDirect() says which it is doing. The check runs a sweep and a floor ray every couple of studs each DirectInterval, so a long clear corridor costs more than a short one; raise the interval for a crowd.

Let the graph do the routing​

Roblox's navmesh re-plans to slightly different waypoints every time, which is fine for one walk and jittery for a chase that re-plans four times a second. With authored nodes, route with the graph and keep the navmesh as the fallback:

:UsePathfinder(VluxyAI.Pathfinders.Hybrid.new({
	Graph = graph,
	Local = VluxyAI.Pathfinders.Navmesh.new(),
	Prefer = "Graph",   -- the graph for every route; the navmesh only when the graph has none
	RefineEnds = false, -- end legs walked straight: the graph picks its end nodes on a clear line
}))
:UseDirect(VluxyAI.Pathfinders.Straight.new()) -- and a target in plain view is walked at straight

Lead a moving target​

A chase that plans to where the player is arrives where the player was. The Navigator measures how fast the MoveTo target moves and plans Lead seconds ahead of it (half a second by default, capped at LeadMax studs, and not within LeadMinDistance so an agent at arms' length does not overshoot); a point ahead that cannot be reached falls back to the target itself. Navmesh shaves off waypoints that turn less than SimplifyAngle degrees (8 by default), so a curve becomes a few long legs instead of a stop at every 2-stud waypoint. Both come from the original VluxyAI pathfinding, where they were tuned by play-testing. agent.Navigator:GetRemainingDistance() is the walk left along the path.

Transitions before Update​

Transitions are checked first, in order, and the first true one wins. Update only runs when none fired. Put the important interrupts (attack range, lost the target) at the top of the list.

Memory lives in the blackboard​

Sight keeps SeenPosition for Memory seconds after losing the target, then clears it. A chase state that transitions out on SeenPosition == nil gets "run to where I last saw them, then give up" for free. Tune Memory per enemy; it is the difference between a stalker and a bloodhound.

Distance is not sight​

Proximity writes NearestDistance through walls; Sight writes SeenDistance only with a clear line. Use the first to decide an attack that does not care about walls (a scream, a shockwave) and the second for one that does.

Utility for targets, transitions for modes​

When a state must choose one of several things, score them with Utility.Best and give the current choice a bonus consideration so the choice is sticky. Do not score the decision to attack or flee; write it as a transition, where you can read it.

Watch the tick​

The default tick is 0.1 seconds. A fast enemy that must freeze the instant it is seen (the Weeping Angel) runs at 0.05. A slow patroller is fine at 0.25. Senses cost raycasts per tick, so the tick is your budget knob.

Give the navmesh a second​

PathfindingService rebuilds its mesh lazily after parts are added. An agent spawned in the same frame as its map will fail its first plan; the navigator retries on its cadence, so this is harmless, but the playground waits a second before spawning so the first path is clean.

Straight legs walk off ledges only if you let them​

Straight checks for floor every few studs and projects its endpoints onto it. With FloorCheck off it is just a sweep, which is fine on a flat arena and wrong on a rooftop.

A kill is the finishing blow​

Attack.State with Kill = "Live" still does plain damage on every hit that does not finish the victim; the live kill only plays for the blow that would bring their health to zero. If you want every hit to be a kill, make Damage at least the victim's health.

return nil under strict​

Under --!strict with the brain annotated as VluxyAI.Brain, an Update must end with return nil when it stays put: the checker wants every path to return a string?. A state with only transitions needs no Update at all, which is the shorter way to say "stay".

Debug views are cheap​

StateLabel and PathVisual exist so you never have to print. Make them right after Build() and destroy them with the agent.