Working across coding assistants raises a simple question: what happened across all those sessions?
Agent Watchtower is my attempt to bring that activity into one place. It observes Claude Code, Codex, and Hermes sessions, collects hook events and logs, and stores the activity in a local SQLite database.
Start with useful questions
I want to understand which sessions were active, how token use changes, and what response times look like. Those questions are more useful to me than a single number claiming to measure productivity.
Keeping the data local also gives the tool a clear boundary. It is an observer of development activity, with a dashboard for exploring it.
Explain the measurements
An estimate calculated from API prices is not necessarily the amount on a subscription invoice. Likewise, active session time is not a verified timesheet. Labels need to make those distinctions clear.
The design goal is to make the activity easier to understand without making the measurements sound more authoritative than they are.
Follow the build
This is a project note about the tool’s purpose, rather than a benchmark report. The implementation and current progress are available in the Agent Watchtower repository.