add description

packages/components/nodes/memory/BufferWindowMemory/BufferWindowMemory.ts

@@ -37,7 +37,8 @@ class BufferWindowMemory_Memory implements INode {
                 label: 'Size',
                 name: 'k',
                 type: 'number',
-                default: '4'
+                default: '4',
+                description: 'Window of size k to surface the last k back-and-forths to use as memory.'
             }
         ]
     }