The Tasha’s Cauldron of Everything brings the most recent version of the Artificer and the Battle Smith subclass, who gains a companion called Steel Defender at level 3. In the description of the Steel Defender ability, there is a part of the text that states:
[…] In combat, the defender shares your initiative coutn, but it takes its turn immediately after yours. It can move and use its reaction on its own, but the only action it takes on its turn is the Dodge action, unless you take a bonus action on your turn to command it to take an action. […]
Altought it states that you have to take an bonus action on your turn to command it to take an action, there is no limitation regarding the distance between the two. Since nothing restricts regarding this condition, by RAW you could command it whenever you are by taking a bonus action. But this sounds off in some cases, like when they are really far apart from each other (miles away for example).
Is there any other official rules that could be used to support a maximum distance between then for the artificer be able to command it?