The Warehouse Caretaker is the agent who has a form of symbiotic connection to the current incarnation of the Warehouse. Their link allows them to actively search through inventory, sense if the Warehouse is in trouble, and above all be a living body for the Warehouse's soul to share. A Caretaker has access to the restricted files on the current and past Warehouse secrets, although the role is separate from that of the Keeper. Should a Warehouse fail to properly deactivate and later reawaken after the death of its original Caretaker, then it will attempt to form a relationship with the Caretaker of the current Warehouse. This can be harmful to the Caretaker, as he or she will not be able keep up with the information of both Warehouses and their brain will be overloaded. If the reawakened Warehouse can be deactivated, then the Caretaker's flow of information will revert to its original state. The same situation occurs when a past Caretaker is revived. The Caretaker is organically connected to the Warehouse, as such as long the Warehouse lives they will live, but if the Warehouse dies they will die.
In "The Truth Hurts", Paracelsus used the Philosopher's Stone on himself to make his connection to the Warehouse stronger than any other previous Caretaker's connection. Paracelsus' connection was so strong he could control every nut, bolt, and artifact inside the Warehouse with just a thought. In the Warehouse's Eldunari, now there was a large rapidly spinning ring of fire. Artie was able to disconnect Paracelsus from the Warehouse by using Sargon the Great's Mirrors to reflect the fire of the ring back into its alcoves.
Although Agents must be replaced with each relocation of the Warehouse, the Caretaker does not necessarily have to come from the country that hosts the Warehouse. Warehouse 2 attempted to bond with Mrs. Frederic, who is from America rather than Egypt; Paracelsus hails from what is now Switzerland, and Warehouse 9 was located in Turkey; the Valda from Paracelsus' alternate timeline attempted to utilize both Claire and himself as Caretakers for Warehouse 14, which would have been situated in China, despite neither of them being born in that country. Additionally, the fact that Paracelsus was able to be Caretaker of multiple Warehouses implies that the Caretaker need not necessarily change whenever the Warehouse moves.
- Paracelsus (Former Caretaker of Warehouse 9 and temporary Caretaker of Warehouse 13)
- Mrs. Frederic's Sister (Original Caretaker of Warehouse 13; perished in the fire that destroyed the original Warehouse 13)
- Mrs. Frederic (Current Caretaker of Warehouse 13)
- Claudia Donovan (Future Caretaker of Warehouse 13 (seen 50 years in the future)
- Vanessa and Mrs. Frederic intended for Claudia to be the next Warehouse Caretaker when Mrs. Frederic's connection to Warehouse 2 nearly closed down her brain. Afterward, she was still the favoured candidate to take over should anything happen to Mrs. Frederic, as Vanessa told her that "she will be ready" when the time comes.
- However, it may may possible that Claudia and the Warehouse already had a bond comparable to a Warehouse and its Caretaker, as immediately after Claudia was de-bronzed, she sensed something was wrong with the Warehouse. When it was suggested that maybe Claudia's mind was clashing with Mrs Fredric's:
- Artie: "But...you and Claudia have always co-existed in harmony..."
- Interestingly, all known Caretakers have had siblings:
- Paracelsus & Bennett Sutton
- Irene Frederick & her sister
- Claudia Donovan & Claire and Joshua Donovan
- Whether or not Alexander the Great himself was a Caretaker, he himself had 5 half-siblings and one true sibling, which may not exactly break the pattern, at least as far as the show has shown.