This is a standalone policy that will kill the sleep process. You can adapt it to make sure that any undesired process is not running.

body common control
{
bundlesequence => { "process_kill" };
}

bundle agent process_kill
{
processes:

  "sleep"

    signals => { "term", "kill" }; #Signals are presented as an ordered list to the process.
                                   #On Windows, only the kill signal is supported, which terminates the process.

}

This policy can be found in /var/cfengine/share/doc/examples/unit_process_kill.cf.

Example run:

# /bin/sleep 1000 &
[1] 5370
# cf-agent -f unit_process_kill.cf
[1]+  Terminated              /bin/sleep 1000
#

Now let's do it again with inform mode turned on, and CFEngine will show the process table entry that matched the pattern we specified ("sleep"):

# /bin/sleep 1000 &
[1] 5377
# cf-agent -f unit_process_kill.cf -IK
2013-06-08T16:30:06-0700     info: This agent is bootstrapped to '192.168.183.208'
2013-06-08T16:30:06-0700     info: Running full policy integrity checks
2013-06-08T16:30:06-0700     info: /process_kill/processes/'sleep': Signalled 'term' (15) to process 5377 (root      5377  3854  5377  0.0  0.0  11352   0   612    1 16:30 00:00:00 /bin/sleep 1000)
[1]+  Terminated              /bin/sleep 1000
#

If we add the -v switch to turn on verbose mode, we see the /bin/ps command CFEngine used to dump the process table:

# cf-agent -f unit_process_kill.cf -Kv
...
2013-06-08T16:38:20-0700  verbose: Observe process table with /bin/ps -eo user,pid,ppid,pgid,pcpu,pmem,vsz,ni,rss,nlwp,stime,time,args
2013-06-08T16:38:20-0700  verbose: Matched 'root      5474  3854  5474  0.0  0.0  11352   0   612    1 16:38 00:00:00 /bin/sleep 1000'
...