Claude Duet harness engineering: seven-stage guide for unattended agents
A practitioner rewrites Anthropic's official 12-minute Claude Duet harness engineering video into a seven-stage shipping guide covering isolated browser, credential proxy and independent checks.
Anthropic put out Claude Duet Harness Engineering today. 12 minutes, official, and it finally spells out the three walls around an unattended agent: isolated browser, credential proxy, independent checks. This is f**king gold, so I rewrote it as a guide for people who ship. Seven stages, one direction: brief -> context -> tools -> observations -> verification -> repair -> delivery. The rules that make the stages hold: -> Every step declares its inputs and its required outputs. -> Tool results, artifact paths and errors get written down, always. -> Checkpoints survive a crash, so the agent resumes, not restarts. -> Output is verified against acceptance checks, not against vibes. -> A failed check goes back for one targeted repair. -> Missing evidence is labeled UNVERIFIED and shipped as such. -> Delivery means files, setup steps and the check results in one packet. On top: five runtime decisions and a worked example, CSV -> searchable comparison board -> checks -> delivery packet. Save this, then read my article on harness engineering for my AI employee ↓
This post quotes another post: x.com/slash1sol/status/2098013767627837827