My Unattended Job Ran on Time and Did Nothing

Description and use

<p><em>This post describes the behavior of specific tool versions on my machine — macOS with bash 3.2 and the Claude Code CLI as of October 2026. Argument-parsing details change; verify against your own versions before copying any of this.</em></p> <p>For two nights in a row, my nightly automation fired exactly on schedule and exited one second later, having done nothing. The scheduler was never the problem. The prompt I fed to the agent CLI happened to start with a line of three dashes — the YAML frontmatter of my runbook file — and the CLI parsed the entire 12-kilobyte prompt as one long com

Problem

<p><em>This post describes the behavior of specific tool versions on my machine — macOS with bash 3.2 and the Claude Code CLI as of October 2026. Argument-parsing details change; verify against your own versions before copying any of this.</em></p> <p>For two nights in a row, my nightly automation fired exactly on schedule and exited one second later, having done nothing. The scheduler was never the problem. The prompt I fed to the agent CLI happened to start with a line of three dashes — the YAML frontmatter of my runbook file — and the CLI parsed the entire 12-kilobyte prompt as one long com

Outcome

<p><em>This post describes the behavior of specific tool versions on my machine — macOS with bash 3.2 and the Claude Code CLI as of October 2026. Argument-parsing details change; verify against your own versions before copying any of this.</em></p> <p>For two nights in a row, my nightly automation fired exactly on schedule and exited one second later, having done nothing. The scheduler was never the problem. The prompt I fed to the agent CLI happened to start with a line of three dashes — the YAML frontmatter of my runbook file — and the CLI parsed the entire 12-kilobyte prompt as one long com

Evidence

My Unattended Job Ran on Time and Did Nothing

Source