The run-id specifies which run of which a report should be produced.
html-dir argument specifies the directory for the HTML report. If not specified, a temporary directory will be created. The file "index.html" is the start page.
The graph-spec-json-file argument points out an json file used for selecting which graphs to produce. If not specified, a default file will be used.
The -open-browser switch starts a web-browser directly on the generated file.
To decrease browser load time, and to make the main-page more high-level, some graphs can request to be added to sub-pages instead of the main page. The -one-page switch prevents this and puts all graphs on the same page.