Roblox Npc Ai

Roblox NPC & AI

Use this skill when creating NPCs, enemies, bosses, or autonomous characters that navigate, detect players, or make decisions.

Quick Reference

PathfindingService

local path = PathfindingService:CreatePath({
    AgentRadius = 2, AgentHeight = 5, AgentCanJump = true,
    Costs = { Water = 20, DangerZone = math.huge },
})
path:ComputeAsync(npcPos, targetPos)
if path.Status ~= Enum.PathStatus.Success then return end
for _, wp in path:GetWaypoints() do
    if wp.Action == Enum.PathWaypointAction.Jump then humanoid.Jump = true end
    humanoid:MoveTo(wp.Position)
    if not humanoid.MoveToFinished:Wait() then return end
end

• Connect path.Blocked to recompute when world changes
• Region modifiers: Anchored part + PathfindingModifier with Label → Costs
• PassThrough = true for doors; PathfindingLink for disconnected navmesh
• math.huge cost = non-traversable

State Machine

idle → patrol → chase → attack → flee → dead

• idle/patrol → chase (player detected) → attack (in range) → idle (lost)
• any → flee (health low) → idle (safe); any → dead (health ≤ 0)
• Transition func handles walk speed changes, clears target on idle

Detection (distance → FOV → LOS)

1. Distance (a-b).Magnitude — cheapest, always first
2. FOV forward:Dot(toTarget) cosine — ~120° cone
3. LOS workspace:Raycast — expensive, last

• Skip dead players. Close-range (~30%) bypasses FOV (hearing)

Spawners

• Track active enemies, cap count, remove on Humanoid.Died
• Clone → PivotTo → parent; task.delay(3, Destroy) for death anim
• Wave: {enemies={{template, count}}, spawnDelay, waveDelay}

Network Ownership — MUST DO

for _, part in model:GetDescendants() do
    if part:IsA("BasePart") then part:SetNetworkOwner(nil) end
end

Without this, exploiters fling NPCs. Server = safe but 30Hz tick.

Update Loop

• Throttle AI to 5-10 ticks/sec, NOT every Heartbeat
• Stagger large batches (5/frame); ALL NPC logic server-side only

Pitfalls

• No path.Blocked handler → stale paths
• No ComputeAsync fallback → frozen NPCs
• MoveTo 8-sec timeout; handle reached = false
• Forget SetNetworkOwner(nil) → exploiters fling NPCs
• Dead corpses not destroyed → memory leak
• 50 NPCs pathfinding same frame → server lag spike

Need more detail? Load references/full.md for the complete reference with code examples, API tables, and edge cases.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: TabooHarmony
• Source: TabooHarmony/roblox-brain
• License: MIT

Install and usage instructions live in the source repository linked above.