Check-in URLs

Every monitor has a unique, unguessable check-in URL. Your job calls it to report what happened. There are three endpoints, all built from the same ping key:

Only the success endpoint is required. The start and fail endpoints are optional and unlock duration tracking and immediate failure alerts.

Success

Call the base URL when the job finishes cleanly:

curl -fsS https://cronwarden.com/ping/your-ping-key

This is the check-in that keeps the monitor "up". If it doesn't arrive within the schedule plus its grace period, the monitor goes late and then down.

Start

Call the /start endpoint at the beginning of the run:

curl -fsS https://cronwarden.com/ping/your-ping-key/start
# ... job runs ...
curl -fsS https://cronwarden.com/ping/your-ping-key

Pairing a start with a success lets CronWarden measure how long the run took (see Run duration) and notice a run that started but never finished.

Fail

Call /fail when your script knows it failed, so you're alerted immediately instead of waiting for the missed check-in:

if ! run_the_job; then
  curl -fsS https://cronwarden.com/ping/your-ping-key/fail
  exit 1
fi
curl -fsS https://cronwarden.com/ping/your-ping-key

Methods and reliability

• Both GET and POST work. Use POST when you want to send a value in a JSON body (see Reporting a value).
• The -fsS flags tell curl to stay quiet on success, show errors, and fail on a non-2xx response — so a check-in problem shows up in your job's own logs.
• The ping key is high-entropy and not guessable; treat the URL as a secret, since anyone who has it can check in on the monitor's behalf.