diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index d71443500151a2..5d05cca6767b45 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -4438,7 +4438,7 @@ int cmd_pack_objects(int argc,
 				N_("protocol"),
 				N_("exclude any configured uploadpack.blobpackfileuri with this protocol")),
 		OPT_BOOL(0, "full-name-hash", &use_full_name_hash,
-			 N_("optimize delta compression across identical path names over time")),
+			 N_("(EXPERIMENTAL!) optimize delta compression across identical path names over time")),
 		OPT_END(),
 	};
 
diff --git a/builtin/repack.c b/builtin/repack.c
index e5f53a6eac7034..15fd5678779437 100644
--- a/builtin/repack.c
+++ b/builtin/repack.c
@@ -1209,7 +1209,7 @@ int cmd_repack(int argc,
 		OPT_BOOL('F', NULL, &po_args.no_reuse_object,
 				N_("pass --no-reuse-object to git-pack-objects")),
 		OPT_BOOL(0, "full-name-hash", &po_args.full_name_hash,
-				N_("pass --full-name-hash to git-pack-objects")),
+				N_("(EXPERIMENTAL!) pass --full-name-hash to git-pack-objects")),
 		OPT_NEGBIT('n', NULL, &run_update_server_info,
 				N_("do not run git-update-server-info"), 1),
 		OPT__QUIET(&po_args.quiet, N_("be quiet")),