Full source for the simple AI written in the get started guide .It should be attached to a GameObject with a Seeker and a CharacterController also attached.
using UnityEngine;
using Pathfinding;
public class AstarAI : MonoBehaviour {
    public Transform targetPosition;
    private CharacterController controller;
    public Path path;
    public float speed = 2;
    public float nextWaypointDistance = 3;
    private int currentWaypoint = 0;
    public float repathRate = 0.5f;
    private float lastRepath = -9999;
    public void Start () {
        seeker = GetComponent<Seeker>();
        controller = GetComponent<CharacterController>();
    }
    public void OnPathComplete (Path p) {
        Debug.Log("A path was calculated. Did it fail with an error? " + p.error);
        
        
        
        
        
        p.Claim(this);
        if (!p.error) {
            if (path != null) path.Release(this);
            path = p;
            
            currentWaypoint = 0;
        } else {
            p.Release(this);
        }
    }
    public void Update () {
        if (Time.time - lastRepath > repathRate && seeker.IsDone()) {
            lastRepath = Time.time+ Random.value*repathRate*0.5f;
            
            
            seeker.
StartPath(transform.position, targetPosition.position, OnPathComplete);
 
        }
        if (path == null) {
            
            return;
        }
        if (currentWaypoint > path.vectorPath.Count) return;
        if (currentWaypoint == path.vectorPath.Count) {
            Debug.Log("End Of Path Reached");
            currentWaypoint++;
            return;
        }
        
        Vector3 dir = (path.vectorPath[currentWaypoint]-transform.position).normalized;
        dir *= speed;
        
        controller.SimpleMove(dir);
        
        
        
        if ((transform.position-path.vectorPath[currentWaypoint]).sqrMagnitude < nextWaypointDistance*nextWaypointDistance) {
            currentWaypoint++;
            return;
        }
    }
}