I spent last Saturday adding per-run cost accounting to my agent fleet. Not a dashboard — a counter that increments on every model call, tagged with the run ID, the tool that fired it, and the person who asked. Ninety lines and one Postgres table.
Source: [Dev.to](https://dev.to/o96a/your-agent-control-plane-is-an-api-gateway-with-a-new-name-1jpp)