diff --git a/tools/hiddenapi/exclude.sh b/tools/hiddenapi/exclude.sh
new file mode 100755
index 0000000..2291e5a
--- /dev/null
+++ b/tools/hiddenapi/exclude.sh
@@ -0,0 +1,57 @@
+#!/bin/bash
+set -e
+# Make sure that entries are not added for packages that are already fully handled using
+# annotations.
+LOCAL_DIR="$( dirname ${BASH_SOURCE} )"
+# Each team should add a <team>_PACKAGES and <team>_EMAIL with the list of packages and
+# the team email to use in the event of this detecting an entry in a <team> package. Also
+# add <team> to the TEAMS list. 
+LIBCORE_PACKAGES="\
+  android.icu \
+  android.system \
+  com.android.bouncycastle \
+  com.android.conscrypt \
+  com.android.okhttp \
+  com.sun \
+  dalvik \
+  java \
+  javax \
+  libcore \
+  org.apache.harmony \
+  org.json \
+  org.w3c.dom \
+  org.xml.sax \
+  sun \
+  "
+LIBCORE_EMAIL=libcore-team@android.com
+
+# List of teams.
+TEAMS=LIBCORE
+
+# Generate the list of packages and convert to a regular expression.
+PACKAGES=$(for t in $TEAMS; do echo $(eval echo \${${t}_PACKAGES}); done)
+RE=$(echo ${PACKAGES} | sed "s/ /|/g")
+git show --name-only --pretty=format: $1 | grep "config/hiddenapi-.*txt" | while read file; do
+    ENTRIES=$(grep -E "^L(${RE})/" <(git show $1:$file))
+    if [[ -n "${ENTRIES}" ]]; then
+      echo -e "\e[1m\e[31m$file $1 contains the following entries\e[0m"
+      echo -e "\e[1m\e[31mfor packages that are handled using UnsupportedAppUsage. Please remove\e[0m"
+      echo -e "\e[1m\e[31mthese entries and add annotations instead.\e[0m"
+      # Partition the entries by team and provide contact details to aid in fixing the issue.
+      for t in ${TEAMS}
+      do
+        PACKAGES=$(eval echo \${${t}_PACKAGES})
+        RE=$(echo ${PACKAGES} | sed "s/ /|/g")
+        TEAM_ENTRIES=$(grep -E "^L(${RE})/" <(echo "${ENTRIES}"))
+        if [[ -n "${TEAM_ENTRIES}" ]]; then
+          EMAIL=$(eval echo \${${t}_EMAIL})
+          echo -e "\e[33mContact ${EMAIL} or compat- for help with the following:\e[0m"
+          for i in ${ENTRIES}
+          do
+            echo -e "\e[33m  ${i}\e[0m"
+          done
+        fi
+      done
+      exit 1
+    fi
+done