diff --git a/doc/manuals/chapters/mgcp_endpoints.adoc b/doc/manuals/chapters/mgcp_endpoints.adoc
index 797fdea..2fb6e16 100644
--- a/doc/manuals/chapters/mgcp_endpoints.adoc
+++ b/doc/manuals/chapters/mgcp_endpoints.adoc
@@ -91,4 +91,10 @@
 not yet useable.
 
 NOTE: the VTY command "show mgcp" can be used to get a list of all available
-endpoints (including identifiers)
\ No newline at end of file
+endpoints (including identifiers)
+
+=== The `null` endpoint
+
+OsmoMGW offers a special `null@<domain>` endpoint which can be audited at all times.
+This is useful for MGCP clients who wish to submit requests to OsmoMGW
+periodically to find out whether it is still reachable and in a working state.
\ No newline at end of file
