diff --git a/README.md b/README.md
index 0149117..27c2f15 100644
--- a/README.md
+++ b/README.md
@@ -135,7 +135,9 @@ export LUMA_MARKDOWN_BIN="$PWD/luma_markdown"
 ```
 
 It registers the `:LumaPreview` command and automatically refreshes the
-preview for `*.luma` files.
+preview for `*.luma` files. Conversion runs asynchronously and is debounced
+while typing, so a slow converter does not block Neovim input; an older
+conversion is discarded when newer buffer contents are available.
 
 ## Development