diff --git a/src/Var.cc b/src/Var.cc
index 0b19d389e2..f7722064f4 100644
--- a/src/Var.cc
+++ b/src/Var.cc
@@ -531,7 +531,8 @@ void begin_func(zeek::detail::IDPtr id, const char* module_name,
 				}
 
 			if ( prototype->deprecated )
-				t->Warn("use of deprecated prototype", id.get());
+				t->Warn(fmt("use of deprecated '%s' prototype", id->Name()),
+				        prototype->args.get(), true);
 			}
 		else
 			{
diff --git a/testing/btest/Baseline/language.alternate-event-hook-prototypes/out b/testing/btest/Baseline/language.alternate-event-hook-prototypes/out
index aa70ccc747..66d22d20e4 100644
--- a/testing/btest/Baseline/language.alternate-event-hook-prototypes/out
+++ b/testing/btest/Baseline/language.alternate-event-hook-prototypes/out
@@ -1,4 +1,4 @@
-warning in /home/jon/pro/zeek/zeek/testing/btest/.tmp/language.alternate-event-hook-prototypes/alternate-event-hook-prototypes.zeek, line 68 and /home/jon/pro/zeek/zeek/testing/btest/.tmp/language.alternate-event-hook-prototypes/alternate-event-hook-prototypes.zeek, line 10: use of deprecated prototype (hook(c:count;) : bool and my_hook)
+warning in /home/jon/pro/zeek/zeek/testing/btest/.tmp/language.alternate-event-hook-prototypes/alternate-event-hook-prototypes.zeek, line 68 and /home/jon/pro/zeek/zeek/testing/btest/.tmp/language.alternate-event-hook-prototypes/alternate-event-hook-prototypes.zeek, line 13: use of deprecated 'my_hook' prototype (hook(c:count;) : bool)
 my_hook, infinite, 13
 my_hook, 13, infinite
 my_hook, infinite
diff --git a/testing/btest/Baseline/language.alternate-prototypes-deprecated-args/out b/testing/btest/Baseline/language.alternate-prototypes-deprecated-args/out
index 8acfd27bf5..0f67248592 100644
--- a/testing/btest/Baseline/language.alternate-prototypes-deprecated-args/out
+++ b/testing/btest/Baseline/language.alternate-prototypes-deprecated-args/out
@@ -1,5 +1,5 @@
 warning in /home/jon/pro/zeek/zeek/testing/btest/.tmp/language.alternate-prototypes-deprecated-args/alternate-prototypes-deprecated-args.zeek, line 9 and /home/jon/pro/zeek/zeek/testing/btest/.tmp/language.alternate-prototypes-deprecated-args/alternate-prototypes-deprecated-args.zeek, line 5: use of deprecated parameter 'b' (event(a:string; b:string; c:string;))
-warning in /home/jon/pro/zeek/zeek/testing/btest/.tmp/language.alternate-prototypes-deprecated-args/alternate-prototypes-deprecated-args.zeek, line 19 and /home/jon/pro/zeek/zeek/testing/btest/.tmp/language.alternate-prototypes-deprecated-args/alternate-prototypes-deprecated-args.zeek, line 5: use of deprecated prototype (event(a:string; b:string;) and myev)
+warning in /home/jon/pro/zeek/zeek/testing/btest/.tmp/language.alternate-prototypes-deprecated-args/alternate-prototypes-deprecated-args.zeek, line 19 and /home/jon/pro/zeek/zeek/testing/btest/.tmp/language.alternate-prototypes-deprecated-args/alternate-prototypes-deprecated-args.zeek, line 7: use of deprecated 'myev' prototype (event(a:string; b:string;))
 myev (canon), one, two, three
 myev (new), one, three
 myev (old), one, two