diff --git a/src/vehicle_cmd.cpp b/src/vehicle_cmd.cpp
--- a/src/vehicle_cmd.cpp
+++ b/src/vehicle_cmd.cpp
@@ -65,7 +65,8 @@ const uint32 _send_to_depot_proc_table[]
  * @param flags type of operation
  * @param p1 vehicle to start/stop
  * @param p2 bit 0: Shall the start/stop newgrf callback be evaluated (only valid with DC_AUTOREPLACE for network safety)
- * @return result of operation.  Nothing if everything went well
+ * @param text unused
+ * @return the cost of this operation or an error
  */
 CommandCost CmdStartStopVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
@@ -122,6 +123,8 @@ CommandCost CmdStartStopVehicle(TileInde
  *   - bit 5 false = start vehicles, true = stop vehicles
  *   - bit 6 if set, then it's a vehicle list window, not a depot and Tile is ignored in this case
  *   - bit 8-11 Vehicle List Window type (ignored unless bit 1 is set)
+ * @param text unused
+ * @return the cost of this operation or an error
  */
 CommandCost CmdMassStartStopVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
@@ -172,6 +175,8 @@ CommandCost CmdMassStartStopVehicle(Tile
  * @param flags type of operation
  * @param p1 Vehicle type
  * @param p2 unused
+ * @param text unused
+ * @return the cost of this operation or an error
  */
 CommandCost CmdDepotSellAllVehicles(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
@@ -201,6 +206,8 @@ CommandCost CmdDepotSellAllVehicles(Tile
  * @param flags type of operation
  * @param p1 Type of vehicle
  * @param p2 If bit 0 is set, then either replace all or nothing (instead of replacing until money runs out)
+ * @param text unused
+ * @return the cost of this operation or an error
  */
 CommandCost CmdDepotMassAutoReplace(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
@@ -314,6 +321,8 @@ static void CloneVehicleName(const Vehic
  * @param flags type of operation
  * @param p1 the original vehicle's index
  * @param p2 1 = shared orders, else copied orders
+ * @param text unused
+ * @return the cost of this operation or an error
  */
 CommandCost CmdCloneVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
@@ -527,6 +536,8 @@ CommandCost SendAllVehiclesToDepot(Vehic
  * @param flags type of operation
  * @param p1 vehicle ID to name
  * @param p2 unused
+ * @param text the new name or an empty string when resetting to the default
+ * @return the cost of this operation or an error
  */
 CommandCost CmdRenameVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
@@ -556,6 +567,8 @@ CommandCost CmdRenameVehicle(TileIndex t
  * @param flags type of operation
  * @param p1 vehicle ID that is being service-interval-changed
  * @param p2 new service interval
+ * @param text unused
+ * @return the cost of this operation or an error
  */
 CommandCost CmdChangeServiceInt(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {