diff --git a/inc/thorvg.h b/inc/thorvg.h
index 89f53ad6..142cd354 100644
--- a/inc/thorvg.h
+++ b/inc/thorvg.h
@@ -1789,7 +1789,10 @@ public:
     ~WgCanvas();
 
     /**
-     * @brief Sets the target window for the rasterization.
+     * @brief Sets the drawing target for the rasterization.
+     *
+     * @param[in] instance WGPUInstance, context for all other wgpu objects.
+     * @param[in] surace WGPUSurface, handle to a presentable surface.
      *
      * @warning Please do not use it, this API is not official one. It could be modified in the next version.
      *