Index: source/blender/editors/mesh/editmesh_tools.c
===================================================================
--- source/blender/editors/mesh/editmesh_tools.c	(revision 45152)
+++ source/blender/editors/mesh/editmesh_tools.c	(working copy)
@@ -2014,6 +2014,7 @@
 {
 	/* identifiers */
 	ot->name = "Merge";
+	ot->description = "Merge selected vertices";
 	ot->idname = "MESH_OT_merge";
 
 	/* api callbacks */
@@ -2065,6 +2066,7 @@
 {
 	/* identifiers */
 	ot->name = "Remove Doubles";
+	ot->description= "Remove duplicate vertices";
 	ot->idname = "MESH_OT_remove_doubles";
 
 	/* api callbacks */
@@ -3605,6 +3607,7 @@
 {
 	/* identifiers */
 	ot->name = "Spin";
+	ot->description = "Extrude selected vertices in a circle around the cursor in indicated viewport";
 	ot->idname = "MESH_OT_spin";
 
 	/* api callbacks */
@@ -3729,6 +3732,7 @@
 {
 	/* identifiers */
 	ot->name = "Screw";
+	ot->description = "Extrude selected vertices in screw-shaped rotation around the cursor in indicated viewport";
 	ot->idname = "MESH_OT_screw";
 
 	/* api callbacks */