--- a/taskcluster/scripts/misc/tooltool-download.sh
+++ b/taskcluster/scripts/misc/tooltool-download.sh
@@ -1,14 +1,28 @@
 # Fetch a tooltool manifest.
 
 cd $WORKSPACE/build/src
 
+case "`uname -s`" in
+Linux)
+    TOOLTOOL_AUTH_FILE=/builds/relengapi.tok
+    ;;
+MINGW*)
+    TOOLTOOL_AUTH_FILE=c:/builds/relengapi.tok
+    ;;
+esac
+
 TOOLTOOL_DL_FLAGS=
 
+if [ -e "$TOOLTOOL_AUTH_FILE" ]; then
+    # When the worker has the relengapi token pass it down
+    TOOLTOOL_DL_FLAGS="${TOOLTOOL_DL_FLAGS=} --authentication-file=$TOOLTOOL_AUTH_FILE"
+fi
+
 if [ -n "$RELENGAPI_PORT" ]; then
     # When the worker has the relengapi proxy setup, use it.
     TOOLTOOL_DL_FLAGS="${TOOLTOOL_DL_FLAGS=} --tooltool-url=http://relengapi/tooltool/"
 fi
 
 : TOOLTOOL_CACHE                ${TOOLTOOL_CACHE:=/home/worker/tooltool-cache}
 export TOOLTOOL_CACHE