diff --git a/README.md b/README.md
index eda1034f..919b0696 100644
--- a/README.md
+++ b/README.md
@@ -239,6 +239,11 @@ Buildkite > (Org, Queue) > TotalAgentsCount
 
 When a queue is specified, only that queue's metrics are published.
 
+We send metrics for Jobs in the following states:
+* **Scheduled**, the job hasn't been assigned to an agent yet. If you have agent capacity, this value should be close to 0.
+* **Waiting**, the job is known to exist but isn't schedulable yet due to dependencies, `wait` statements, etc. This information is mostly useful to an autoscaler, since it represents work that will start soon.
+* **Running**, an agent is actively executing this job.
+
 ## License
 
 See [LICENSE.md](LICENSE.md) (MIT)