Added auto-setup IK script

Assets/Editor/HelperMenu.cs

 using System.Collections.Generic;
 using UnityEditor;
 using UnityEngine;
+using UnityEngine.Animations.Rigging;
 
 public class MirrorTransformWindow : EditorWindow
 {
 
     private Vector4 m_Plane = new Vector4(1f, 0f, 0f, 0f);
 
-    [MenuItem("Animation Rigging/Mirror Transforms", false, 0)]
+    [MenuItem("Animation Rigging/Utilities/Mirror Transforms", false, 0)]
     static void ShowWindow()
     {
         MirrorTransformWindow window = EditorWindow.GetWindow<MirrorTransformWindow>();
 
         return reflectionMat;
 	}
+
+    [MenuItem("Animation Rigging/Utilities/Auto-Setup TwoBoneIK from Tip Transform", false, 0)]
+    public static void TwoBoneIKAutoSetup2(MenuCommand command)
+    {
+        var selection = Selection.activeObject as GameObject;
+        if (!selection)
+        {
+            Debug.LogWarning("Please select a TwoBoneIK before running auto setup.");
+            return;
+        }
+
+        var constraint = selection.GetComponent<TwoBoneIKConstraint>() ;// command.context as UnityEngine.Animations.Rigging.TwoBoneIKConstraint;
+        var tip = constraint.data.tip ;// constraint.data.tip;
+        var animator = constraint.GetComponentInParent<Animator>()?.transform;
+
+        if (!tip)
+        {
+            Debug.LogWarning("Please provide a tip before running auto setup.");
+            return;
+        }
+
+        if (!constraint.data.mid)
+        {
+            Undo.RecordObject(constraint, "Setup mid bone for TwoBoneIK");
+            constraint.data.mid = tip.parent;
+        }
+
+        if (!constraint.data.root)
+        {
+            Undo.RecordObject(constraint, "Setup root bone for TwoBoneIK");
+            constraint.data.root = tip.parent.parent;
+        }
+
+        if (!constraint.data.target)
+        {
+            var target = constraint.transform.Find(constraint.gameObject.name + "_target");
+            if (target == null)
+            {
+                var t = new GameObject();
+                Undo.RegisterCreatedObjectUndo(t, "Created target");
+                t.name = constraint.gameObject.name + "_target";
+                t.transform.localScale = .1f * t.transform.localScale;
+                Undo.SetTransformParent(t.transform, constraint.transform, "Set new parent");
+                target = t.transform;
+            }
+            constraint.data.target = target;
+        }
+
+        if (!constraint.data.hint)
+        {
+            var hint = constraint.transform.Find(constraint.gameObject.name + "_hint");
+            if (hint == null)
+            {
+                var t = new GameObject();
+                Undo.RegisterCreatedObjectUndo(t, "Created hint");
+                t.name = constraint.gameObject.name + "_hint";
+                t.transform.localScale = .1f * t.transform.localScale;
+                Undo.SetTransformParent(t.transform, constraint.transform, "Set new parent");
+                hint = t.transform;
+            }
+            constraint.data.hint = hint;
+        }
+
+        // align target and hint to bones
+        constraint.data.target.position = constraint.data.tip.position;
+        constraint.data.target.rotation = constraint.data.tip.rotation;
+
+        constraint.data.hint.position = constraint.data.mid.position;
+        constraint.data.hint.rotation = constraint.data.mid.rotation;
+    }
+
+
 }

Assets/Scenes/SampleSceneNinja.unity

   m_ReflectionIntensity: 1
   m_CustomReflection: {fileID: 0}
   m_Sun: {fileID: 2138677392}
-  m_IndirectSpecularColor: {r: 0.28502673, g: 0.371393, b: 0.49601054, a: 1}
+  m_IndirectSpecularColor: {r: 0, g: 0, b: 0, a: 1}
   m_UseRadianceAmbientProbe: 0
 --- !u!157 &3
 LightmapSettings:
   - component: {fileID: 772315690}
   - component: {fileID: 772315689}
   m_Layer: 0
-  m_Name: FullBodyRig
+  m_Name: ControlRig
   m_TagString: Untagged
   m_Icon: {fileID: 0}
   m_NavMeshLayer: 0

Assets/Scenes/SampleSceneNinja2.unity.meta

+fileFormatVersion: 2
+guid: b4686011f6080b24ab3b0e6752ff79d1
+DefaultImporter:
+  externalObjects: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Assets/TestNinja/Content/Characters/Ninja/Prefabs/Workshop.meta

+fileFormatVersion: 2
+guid: 5eeac501838aa88408946952586b815a
+folderAsset: yes
+DefaultImporter:
+  externalObjects: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Assets/TestNinja/Content/Characters/Ninja/Prefabs/Workshop/NinjaRig_01_Start.prefab.meta

+fileFormatVersion: 2
+guid: 678948e8d26321d449ebdf8096ff60d5
+PrefabImporter:
+  externalObjects: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: