Watchtower
Reading the Watchtower pill
Green, Amber, Red, with the 30-day alert count.
Green: no open rule fired in 30 days. Amber: a Medium or Low rule is open, or evidence expires within 30 days. Red: a High or Critical rule is open, or a protective flag is set. The pill is the only orange or red next to a score.
The public catalogue on the Watchtower page lists every rule, and says for each whether it can fire today and, where it cannot, why. A rule that cannot fire is not a green light.