seems the only indicator is when you are trading with them and want to give them something, if it's too heavy for them to carry it will be greyed out in your inventory so you cannot select it to give to them.
seems the only indicator is when you are trading with them and want to give them something, if it's too heavy for them to carry it will be greyed out in your inventory so you cannot select it to give to them.
Someone mentioned on another thread that you can still make them pick items up from the floor beyond this overencumbered point though, never tested it yet myself.