diff --git a/src/tosca/xtarget/tosca_keys.xtarget b/src/tosca/xtarget/tosca_keys.xtarget
new file mode 100644
index 0000000..ad235e5
--- /dev/null
+++ b/src/tosca/xtarget/tosca_keys.xtarget
@@ -0,0 +1,5 @@
+TOSCA_KEYS = {
+{%- for m in proto.messages %}
+    '{{ m.name }}': {{ xproto_fields_to_tosca_keys(m.fields + xproto_base_fields(m, proto.message_table)) }},
+{%- endfor %}
+}
\ No newline at end of file