diff --git a/scripts/cmake/vcpkg_from_github.cmake b/scripts/cmake/vcpkg_from_github.cmake
index 0ce485954c1..645690353a7 100644
--- a/scripts/cmake/vcpkg_from_github.cmake
+++ b/scripts/cmake/vcpkg_from_github.cmake
@@ -23,7 +23,9 @@
 ## The organization or user and repository on GitHub.
 ##
 ## ### REF
-## A stable git commit-ish (ideally a tag) that will not change contents.
+## A stable git commit-ish (ideally a tag) that will not change contents. **This should not be a branch.**
+##
+## For repositories without official releases, this can be set to the full commit id of the current latest master.
 ##
 ## If `REF` is specified, `SHA512` must also be specified.
 ##
@@ -38,7 +40,7 @@
 ## For most projects, this should be `master`. The chosen branch should be one that is expected to be always buildable on all supported platforms.
 ##
 ## ## Notes:
-## At least one of `REF` and `HEAD_REF` must be specified.
+## At least one of `REF` and `HEAD_REF` must be specified, however it is preferable for both to be present.
 ##
 ## This exports the `VCPKG_HEAD_VERSION` variable during head builds.
 ##