How to list all users in the mongo shell?

You can do:

db.getUsers()

show users

The both commands print a list of users for the current database. See MongoDB documentation for User Management.

mongodb command mongo-shell

List belong to db users:

use db_name and db.getUsers() or show users

List according the authentication type:

db.getUsers({ filter: { mechanisms: "SCRAM-SHA-256" } })

List with the credental:

db.getUsers( {showCredentials: true,  filter: { mechanisms: "SCRAM-SHA-256" }} )

mongodb command mongo-shell

If you like to list only user names and leave all other bulk info.. try

db.system.users.find({}, {"_id" : 1})

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