-# The following variables should be declared in the Makefile:
-# BUNDLES the space-separated list of bundles to be built
-# A2_CATEGORY the a2 category the bundles will belong to
-#
-# The following variables have default values which can be overriden in the Makefile
+# The following variables should be declared in the including Makefile:
+# BUNDLES the space-separated list of bundles to build
+# A2_CATEGORY the (single) a2 category the bundles will belong to
+
+# The following environment variables can change the behaviour of the build
+# SOURCE_BUNDLES sources will be packaged separately in Eclipse-compatible source bundles
+# NO_MANIFEST_COPY generated MANIFESTs won't be copied to the source tree
+
+# The following variables have default values which can be overriden