cannot build debian package

[hramrach]

[ 23s] Running build time source services...
[ 23s] dpkg-source: error: missing critical source control field Files
[ 23s] -----------------------------------------------------------------
[ 23s] ----- building sensors.dsc (user abuild)
[ 23s] -----------------------------------------------------------------
[ 23s] -----------------------------------------------------------------
[ 23s] Recipe file 'sensors.dsc' is being checked for 'DEBTRANSFORM-FILES'... found
[ 23s] DEBTRANSFORM-FILES:
[ 23s] '--include-binaries' will use with dpkg-source
[ 24s] -bash: line 1: cd: /usr/src/packages/BUILD: No such file or directory

There is no documentation of the special debtransform tags so I have absolutely no idea what can possibly be wrong.

[hramrach]

There is a wiki page here https://en.opensuse.org/openSUSE:Build_Service_Debian_builds but it does not describe the debtransform-special tags.