Notes from building and running a lead-and-specialists agent architecture on real work: what the shape was, which decisions held up, where it broke, and what happened when I tried to measure any of it.
Each part stands on its own. They share a subject, not a plot.
If you read nothing else: almost every failure in here was something that looked like a control and wasn’t. An instruction that was really a suggestion. A guard that was really unwired. A default that was really someone else’s config. A clean 2/2 that was really one opinion counted twice. Agent systems generate a great deal of plausible evidence that things are fine, and the engineering problem is building the few things that produce evidence you can rely on — then being clear-eyed about which is which.
The three parts, in one line each:
| Part | Thesis | |
|---|---|---|
| 1 | Running a team of coding agents | Coordination state that lives only in a context window is not coordination |
| 2 | Measuring whether any of it worked | The reviewer briefs mattered more than the architecture, and my first clean result was an artefact of my own writing |
| 3 | Controls that aren’t controls | Guards that live in a settings file on my machine were never controls at all on anyone else’s |
More parts are planned — bounded autonomy, and working across projects — and will appear here when they’re written.
Part 2’s numbers come from harnesses in the repository behind this site. Every superseded version of the reviewer briefs and their results is kept, because the progression is the point.
harness/ —
reviewer gate eval. 12 Go diffs, 8 with a planted defect and 4 clean, two of the
clean ones designed as bait so that a reviewer which blocks everything scores badly
rather than well. Three versions of the briefs and their results.harness2/ —
cross-project eval, cold sessions, one task each.harness3/ —
cross-project eval, persistent sessions, three sequential tasks with a cumulative
integration check.harness/README.md
has the method and, more usefully, what it does not measure.
One model wearing two hats, twelve cases, and defects planted by the same person who wrote the reviewer briefs and the scoring. Reviewers saw a diff and a snippet, not a working tree they could build or test. Read the numbers as an order of magnitude. The finding that survives is about how much the definitions matter, not about any particular score.
The prose is CC BY 4.0 — quote and republish it freely with attribution. The harness code is MIT.