diff --git a/doc/efun/coroutinep b/doc/efun/coroutinep
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+SYNOPSIS
+        int coroutinep(mixed arg)
+
+DESCRIPTION
+        Returns 1 if the argument is a coroutine.
+
+HISTORY
+        Introduced in LDMud 3.6.5.
+
+SEE ALSO
+        bytesp(E), clonep(E), closurep(E), floatp(E), intp(E), lpctypep(E),
+        lwobjectp(E), mappingp(E), objectp(E), pointerp(E), referencep(E),
+        stringp(E), structp(E), symbolp(E)