Crontinel is an open-source monitoring tool designed for Laravel applications, with additional support for Node.js and Python. It watches Laravel schedulers, Horizon queues, workers, backups, and agent runs, detecting failures that standard uptime checks miss. While traditional monitoring confirms that a URL responds, Crontinel hooks directly into the scheduler and queue system to verify that scheduled tasks actually execute, queue workers are draining jobs, and agent runs are not looping. The tool uses a single SDK that integrates with the framework's events rather than requiring per-task instrumentation. The monitoring covers scheduled task run attempts, exit codes, and durations, as well as per-worker status, queue depth trends, failed job rates, and agent tool calls. Missed runs trigger alerts before the next cron tick, with detection within approximately 60 seconds. Alerts can be routed to Slack, PagerDuty, email, or webhooks, with support for HMAC-signed payloads, quiet hours, and per-service routing. The platform includes a local dashboard and CLI, and offers both a free hosted plan and a self-hosted option under an MIT license. Setup requires a single command and does not require changes to existing jobs or scheduler wrapping. Typical use cases include detecting silently removed cron entries, stuck overlap locks, queue workers that are running but not processing jobs, and agent loops consuming resources. The tool also provides a post-deploy verification command that checks scheduler, supervisors, and queues. Data tracked includes run history, queue depth, oldest job age, failure rates, and for agent runs, token spend and model latency. An MCP interface allows agents to query the system with questions about queue backups or agent status.