In addition to custom context items, you can also add "Glows" to your application.
Glows allow you to add little pieces of information, that can later be found in a chronological order in the "Debug" tab of your application.
You can think of glows as breadcrumbs that can help you track down which parts of your code an exception went through.
The Flare PHP client allows you to add a glows to your application like this:
$flare->glow('This is a message from glow!', MessageLevels::DEBUG, func_get_args());