diff --git a/libc/include/sys/syslog.h b/libc/include/sys/syslog.h
index 7761ece..4b89c10 100644
--- a/libc/include/sys/syslog.h
+++ b/libc/include/sys/syslog.h
@@ -1 +1,10 @@
+#pragma once
+
+/**
+ * @file sys/syslog.h
+ * @brief Historical synonym for `<syslog.h>`.
+ *
+ * New code should use `<syslog.h>` directly.
+ */
+
 #include <syslog.h>