diff --git a/SPEC.md b/SPEC.md
index a3866c2c..e368aeaf 100644
--- a/SPEC.md
+++ b/SPEC.md
@@ -195,6 +195,7 @@ Note that logging mechanisms other than stdout and stderr are not required by th
 * **USER, LOGNAME** username of the user executing this app
 * **HOME** home directory of the user
 * **SHELL** login shell of the user
+* **TERM** terminal type if app is started on a tty/pty device; if application inherits stdio from host and it is a terminal, `$TERM` is copied from host environment.
 * **AC_APP_NAME** name of the application, as defined in the image manifest
 * **AC_METADATA_URL** URL where the metadata service for this container can be found