Hashicorp Vault has become one of my favorite technologies over the past year. Secrets management is a non-trivial undertaking, and I'm routinely blown away by how easy vault makes secrets management. One nifty thing I recently learned is vault has auto-completion, which you can enable with the "-autocomplete-install" option:
$ vault -autocomplete-install && source $HOME/.bashrc
Once enabled, you can type vault followed by a tab to see all of the available options:
$ vault tab
agent delete login plugin secrets token
audit kv namespace policy server unwrap
auth lease operator print ssh write
debug list path-help read status
This also works for subcommands, so typing $(vault audit TAB) will display the options that can be passed to the audit sub-command. I'm a huge fan of auto-completion, and try to use it whenever I can to improve my efficieny.