working with ldap browsers

this question is related to

https://social.technet.microsoft.com/Forums/windowsserver/en-US/c7db0c7e-8ea4-46f4-89fe-c8792a2a559a/what-rights-to-give-an-ldap-application?forum=winserverDS#7f8258c4-4b80-45b3-99fe-8ebb13eb0239

as i want to help the vendor with their LDAP authentication so i installed an LDAP browser and tried to make a connection from it. from what i can tell, i am unable to browse my AD tree UNLESS theinitial credentials that i use in this LDAP browser is a domain admin. that is fine with me but what about those vendors? i cannot provide them admin credentials in order to do an LDAP bind.

is this how you normally bind with an LDAP tool? use an admin credential? i was under the impression that any domain user can read the AD tree.