Integrated Tool
Wondrous Item, Common (Requires Use by a Warforged)
Cost: 100 gp
This item attaches to the body of a warforged, and is designed to serve as one of the following tools that weighs 10 pounds or less: an Artisan's Tool, Forgery Kit, Herbalism Kit, Poisoner's Kit, Thieves' Tools, or a Musical Instrument.
You must incorporate the tool into your body before you can use it. Over the course of 1 hour, you can attach the tool or remove it from your body, remaining in contact with it for the whole hour; this can be done over a Short or Long Rest.
While you're alive, the tool can't be removed from your body against your will. Though the tool has become part of your body, you must still have a hand free to make use of it. You can only have one Integrated Tool attached to your body at a time.
Warforged and Prosthetic Limbs
Eberron: Rising from the Last War introduces the Prosthetic Limb, a Common magic item requiring Attunement which predates the warforged. Prosthetic Limbs come in many forms; one might resemble an organic limb of animated wood, and another could be a metal shell or a construct of force. During the Last War, Karrnath made use of skeletal prosthetics, and more recently, Cannith and Jorasco have produced prosthetics that use the same semiorganic materials as the warforged.
Eberron: Rising from the Last War also includes two magic items designed to integrate into a Warforged's forearm: the Armblade and the Wand Sheath. At the DM's discretion, a character of a different species might be able to integrate one of these warforged items into their Prosthetic Limb; the question is if the two can logically work together, or if the style of your prosthetic makes it implausible that it could mesh with a warforged component. If the DM decides it's possible to integrate a component item with the prosthetic, the two could be counted as a single magic item for the purpose of determining the number of magic items you can attune to. If you remove the component from the prosthetic, you immediately lose your Attunement to the component.