add x_revision directive to footer

1 files changed, 4 insertions, 0 deletions

diff --git a/README.md b/README.md
index 0d9c560..67c11d7 100644
--- a/README.md
+++ b/README.md
@@ -47,6 +47,10 @@ This script will edit the given file in-place and make several changes.
 The script will automatically detect if a matching `configs/{song-name}.json` file exists and pass it to the `chordpro` executable to be mixed with/override the global `./config.json` file.
 Once complete, the output file(s) can be found at `./out/{song-title}.{format}`.
 
+The script will also parse any `{x_???:val}` directive and add it as a `--meta` argument to the chordpro command.
+Each chordpro file should at a minimum include a `{x_revision:1}` directive.
+This value is printed in the footer; see `./config.json` for the global footer definition.
+
 For a list of all available output formats, see the official `chordpro` command [output documentation](https://www.chordpro.org/chordpro/using-chordpro/#output).
 
 #### *NOTE:*