NASA will install the RiTS (Robotic Tool Stowage) for RELLs (Robotic External Leak Locators) outside the ISS. Robots will be in it when they are not needed for work. This is stated on the NASA website.
The first inhabitants of the “hotel” will be two RELL robots, which are used to search for leaks outside the station. In RiTS, robots will be protected from potential cosmic threats – including radiation, temperature extremes and micrometeorites.
The “hotel” will also make it easier for Dextre’s robor arm to find and run RELL if necessary. Previously, robots were stored inside the ISS, but space at the station is limited, and new equipment for experiments is constantly being delivered to it. Therefore, the devices decided to place outside the station: this will save time and resources for their deployment, and the crew will not have to go into outer space.
RELL robots are able to capture the presence of various gases, including ammonia. Devices were needed due to air leaks, which are usually caused by micrometeorites. The first robot was launched in 2015, but it was so successful at finding leaks that in 2019, NASA added a backup device.