diff --git a/libvips/iofuncs/object.c b/libvips/iofuncs/object.c
index 2ce9d4da..2fb752db 100644
--- a/libvips/iofuncs/object.c
+++ b/libvips/iofuncs/object.c
@@ -2909,7 +2909,7 @@ vips_object_print_all_cb( VipsObject *object, int *n )
 	fprintf( stderr, "\n" ); 
 
 	vips_object_summary_class( class, &buf );
-	vips_buf_appends( &buf, " " );
+	vips_buf_appends( &buf, ", " );
 	vips_object_summary( object, &buf ); 
 	fprintf( stderr, "%s\n", vips_buf_all( &buf ) );
 
diff --git a/libvips/iofuncs/operation.c b/libvips/iofuncs/operation.c
index c81cd18a..b8537bba 100644
--- a/libvips/iofuncs/operation.c
+++ b/libvips/iofuncs/operation.c
@@ -504,9 +504,9 @@ vips_operation_vips_operation_print_summary_arg( VipsObject *object,
 {
 	VipsBuf *buf = (VipsBuf *) a;
 
-	/* Just assigned required input construct args
+	/* Just assigned input construct args
 	 */
-	if( (argument_class->flags & VIPS_ARGUMENT_REQUIRED) &&
+	if( (argument_class->flags & VIPS_ARGUMENT_INPUT) &&
 		(argument_class->flags & VIPS_ARGUMENT_CONSTRUCT) &&
 		argument_instance->assigned ) {
 		const char *name = g_param_spec_get_name( pspec );