You can do this by editing the App.config (Visual Studio) or leanft.project (Eclipse) file. At the bottom is the Report Section. You need to uncomment this section and set the options as desired.

This is my description

The file contains a description of the values and their meanings:
========================================
Report Section.
Available Report options.
=========================================

heading (optional):

title (optional): Title heading in the HTML Report. When not defined, the title is 'Run Results'.

description (optional): Description displayed below the title in the HTML Report. When not defined, no description is included.

output (optional):

target-directory (optional): Location of generated report folder. Default path is the project Output path.

report-folder (optional): Name of the report folder.
- Default: ''RunResults''

override-existing (optional): Indicates whether the existing report folder is overwritten on each run. If false, each report folder gets an ordinal suffix.

- Default: true

filter (optional):

level (optional): Minimal level of events to be included to the report. The possible values are:

- All (default)

- Warning

- Error

- Off

media (optional):

snapshots (optional):

level (optional): Condition for attaching snapshots to the report. The possible values are:

- All

- OnError

- Off (default)