diff --git a/documentation/ref-manual/ref-variables.xml b/documentation/ref-manual/ref-variables.xml
index b9b0dfc09a..5661a86907 100644
--- a/documentation/ref-manual/ref-variables.xml
+++ b/documentation/ref-manual/ref-variables.xml
@@ -5565,6 +5565,13 @@ recipes-graphics/xorg-font/font-alias_1.0.3.bb:PR = "${INC_PR}.3"
SDK_DIR = "${WORKDIR}/sdk"
+
+ The SDK_DIR directory is a
+ temporary directory as it is part of
+ WORKDIR.
+ The final output directory is
+ SDK_DEPLOY.
+
@@ -5599,6 +5606,15 @@ recipes-graphics/xorg-font/font-alias_1.0.3.bb:PR = "${INC_PR}.3"
SDK_OUTPUT = "${SDK_DIR}/image"
+
+ The SDK_OUTPUT directory is a
+ temporary directory as it is part of
+ WORKDIR by way of
+ SDK_DIR.
+ The final output directory is
+ SDK_DEPLOY.
+
+