diff --git a/tools/build-docs b/tools/build-docs
index 5b8dca523e..0e50923e39 100755
--- a/tools/build-docs
+++ b/tools/build-docs
@@ -5,16 +5,30 @@ from lib import sanity_check
 
 sanity_check.check_venv(__file__)
 
+import argparse
 import os
 import sys
 
 ZULIP_PATH = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
 sys.path.append(ZULIP_PATH)
-from scripts.lib.zulip_tools import run
+from scripts.lib.zulip_tools import ENDC, WARNING, run
 
 
 def main() -> None:
+    parser = argparse.ArgumentParser()
+    parser.add_argument("-c", "--clean", action="store_true")
+    args = parser.parse_args()
+
     path = os.path.join(ZULIP_PATH, "docs")
+    if not args.clean:
+        run(["make", "html", "-C", path])
+        print(
+            WARNING
+            + "tools/build-docs --clean is necessary for the navigation/left sidebar to update."
+            + ENDC
+        )
+        return
+
     run(["make", "clean", "html", "-C", path])