FastCGI - missing FCGI_STDIN

I have a self-created FastCGI app accessed from another web server (not Apache) for decades.

I am now trying to make it work with OpenLiteSpeed.

When my FastCGI app gets a request, I get FCGI_BEGIN_REQUEST and FCGI_PARAMS. Consulting the "original" specification in (section B. Typical Protocol Message Flow) I am missing both the "end" FCGI_PARAMS with zero length and the
FCGI_STDIN with zero length.

Is there a configuration setting that I am missing?

Any comment on this is appreciated.
After some more "digging" I can see the FCGI_PARAMS with contentLength=0 and the FCGI_STDIN with contentLength=0 at the end of the data from OLS. It is probably some problems with my FastCGI app that has not been a problem with the other web server.