diff --git a/README.md b/README.md
index e546e8de9d..56d269c177 100644
--- a/README.md
+++ b/README.md
@@ -274,6 +274,7 @@ See [jgrpp-changelog.md](jgrpp-changelog.md) for changelog.
* Various minor fixes, see changelog.
* [NewGRF specification additions](docs/newgrf-additions.html) ([online copy](https://htmlpreview.github.io/?https://github.com/JGRennison/OpenTTD-patches/blob/jgrpp/docs/newgrf-additions.html)).
* [NML specification additions](docs/newgrf-additions-nml.html) ([online copy](https://htmlpreview.github.io/?https://github.com/JGRennison/OpenTTD-patches/blob/jgrpp/docs/newgrf-additions-nml.html)).
+ * [AI/GS script additions](docs/script-additions.html) ([online copy](https://htmlpreview.github.io/?https://github.com/JGRennison/OpenTTD-patches/blob/jgrpp/docs/script-additions.html)).
* [Low-level code/performance changes](docs/jgrpp-low-level-changes.md).
* Translations
diff --git a/docs/jgrpp-low-level-changes.md b/docs/jgrpp-low-level-changes.md
index ddfb261391..7fa73ffeff 100644
--- a/docs/jgrpp-low-level-changes.md
+++ b/docs/jgrpp-low-level-changes.md
@@ -117,6 +117,7 @@ Pre-filter SaveLoad descriptor arrays for current version/mode, for chunks with
### AI/GS
+[AI/GS script additions](docs/script-additions.html).
Add AI/GS method to get current day length.
Add GS method to create river tiles.
Add workaround for performance issues attempting to create a town when no town names are left.
diff --git a/docs/script-additions.html b/docs/script-additions.html
new file mode 100644
index 0000000000..16bce206fc
--- /dev/null
+++ b/docs/script-additions.html
@@ -0,0 +1,44 @@
+
+
+
+
+ JGR's Patchpack - Additions to Script Specifications (AI and GameScript)
+
+
+
+ Additions to AI/GS Script Specifications in JGR's Patchpack
+ This document describes non-standard additions to the Official OpenTTD AI and GS Specifications which are present in this patchpack.
+
These additions MAY also be present in other patchpacks. They MAY be removed or moved in future, if necessary.
+
+ Scripts which use any of these features SHOULD check whether the feature is present and if not, fallback to not using it and/or emitting a clear and end-user friendly error message.
+ Testing for the presence of methods may be done using the "in" operator.
+
+
+
+
Additional Static Public Member Functions:
+
+
static int32 GetDayLengthFactor ()
+
Get current day length factor
+
+
+
Additional Static Public Member Functions:
+
+
static bool BuildRiver (TileIndex tile)
+
Builds a river on tile (subject to permissions/settings)
+
All other details are the same as BuildCanal
+
+