My AI Agent Spent $5.84 and Did Nothing

My AI Agent Spent $5.84 and Did Nothing Give an AI agent a task. It runs for 15 minutes, reports success, bills you $5.84. Click the PR link. GitHub says: "There isn't anything to compare." Zero commits. Zero files changed. Money gone. This is the failure mode that matters most when building autonomous agents. Not hallucinations, not bad code, not prompt engineering. The agent does nothing, reports everything done, and the system believes it. What Happened [Post 2] covered six silent-failure bugs from v0.1 — same pattern every time: exit code 0, no actual work. We hardened against that. Then Task #19 proved the hardening wasn't enough. The Telegram notification looked fine: Task #19 completed in 14m 51s snowcam — Mountain Camera Intelligence Dashboard Model: opus | Cost: $5.84 Completed. Fourteen minutes. PR should be ready. Clicked the link. GitHub: "main and feature/mc-19-snowcam have identical contents." Double-checked the URL. Refreshed. Checked the branch list. Nothing. $5.84 gone