dbs/mss/verbose is a SAP Parameter attribute which is used to control additional (verbose) trace output by dbsl interface information. This is available within R/3 SAP systems depending on the version and release level.
Below is the standard documentation available and a few details of the attributes values .
Adds some informational messages to the dev_w?? files. These are
mostly messages when exceptional conditions occur or informational
messages during startup. It should not be a problem leaving this
parameter on even during production. The amount of extra information
during routine processing should be minimal.
This parameter is useful for displaying which other profile para-
meters are read by the dbsl release. At startup the name of each
parameter being used and the associated value is written into
dev_w??.
See SAP Parameter Documentation for full SAP documentation for this profile parameter.