I’ve added a couple of LDAP reference documents.
The LDAP Result Code Reference provides a fairly complete overview of many LDAP result codes, including the core LDAPv3 result codes defined in RFC 4511, server-side result codes from other specifications, and client-side result codes. It describes each of the result codes and some of the cases in which they may be used.
The LDAP OID Reference lists a number of object identifiers used throughout LDAP for things like schema elements, controls, and extended operations. It lists the OIDs, provides a brief explanation of its purpose, and, when applicable, provides a link to the relevant specification.
Both of these will also be included in the documentation for the next release of the UnboundID LDAP SDK for Java (and they’re already checked into the GitHub repository), but for now, you can find them on my website.