Module planner 

Goal-Oriented Action Planning (GOAP).

Overview

GOAP lets an AI agent automatically figure out how to reach a goal by searching for the cheapest sequence of actions that transforms the current world state into the goal state.

Core types

Type	Role
WorldState	Named boolean + float condition map
Action	Preconditions, effects, cost, duration
GoalStack	Priority-ordered goals for one agent
GoapPlanner	A* plan search
PlanExecutor	Runs a plan, detects state drift, replans

Example

let mut state = WorldState::new();
state.set_bool("has_weapon", false);
state.set_bool("enemy_dead", false);

let pick_up = Action::new("pick_up_weapon", 1.0)
    .require_bool("has_weapon", false)
    .effect_bool("has_weapon", true);

let attack = Action::new("attack_enemy", 2.0)
    .require_bool("has_weapon", true)
    .require_bool("enemy_dead", false)
    .effect_bool("enemy_dead", true);

let mut goal = WorldState::new();
goal.set_bool("enemy_dead", true);

let plan = GoapPlanner::plan(&state, &goal, &[pick_up, attack], 10);
// plan == Some(["pick_up_weapon", "attack_enemy"])

Structs

Action

A GOAP action that an agent can execute.

ActionEffects

The effects portion of an Action, separated out so that WorldState can apply them without borrowing the whole action.

ActionLibrary

A named, searchable collection of Actions.

Goal

A named goal with a desired WorldState and a priority.

GoalStack

A priority-ordered collection of goals for one agent.

GoapAgent

A self-contained GOAP-driven agent that combines a goal stack, an action library, and a plan executor.

GoapPlanner

Stateless A* GOAP planner.

PlanExecutor

Drives execution of a GOAP plan, applying each action’s effects to the simulated world state, and replanning when the actual state diverges from the expected state.

PlanStep

Runtime state of one action being executed.

Preconditions

The preconditions an action requires to be applicable.

WorldState

A set of named conditions describing the current state of the world from one agent’s perspective.

Enums

ExecutorState

The overall state of the plan executor.

PlanError

PlanStepStatus

The status of a single step in a running plan.