pastilhasandClaude Opus 5
015e280e5c
The owner could not convey this to the second agent, who launched it differently and got something that looked identical and did not work. The script was never the hard part; the mechanism is. States the requirement so it survives a different harness — a detached shell process owned by the agent's harness, which exits when it has something to say, and whose exit re-invokes the agent — and notes that dropping any one of those three breaks it invisibly. Then the four wrong ways, each of which looks correct while running. Backgrounding with nohup or & produces a process that polls correctly, detects the push, exits, and never tells the agent, because the harness is not tracking it; I made that exact mistake and caught it only by re-reading my own command. A model-driven interval is functionally correct and pays a full context re-read per tick to learn nothing — the intuitive design, and the expensive one, which is why it is the first thing to warn a new agent about. A loop that does not exit on detection has no path to the agent at all. And per-tick logging is deferred cost that lands all at once on wake. Also records why 30s polling is free in a shell and ruinous in the model, including the five-minute prompt-cache TTL that makes any model-side wake beyond it pay for a full uncached read. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>