nRF Util's sdk-manager is a CLI tool for managing SDK and toolchain installations for the nRF Connect SDK.
Each version of the nRF Connect SDK has an associated toolchain, which includes tools and modules specific to the nRF Connect SDK that are required to build nRF Connect SDK samples and applications. Multiple SDK versions can share the same toolchain version (for example, the nRF Connect SDK v2.4.1 is reusing the toolchain v2.4.0).
Note: sdk-manager has replaced the toolchain-manager nRF Util command.
The sdk-manager command is able to detect the toolchains installed with toolchain-manager.