If an agent job fails due to the error

Traceback (most recent call last):
  File "/home/frappe/agent/repo/agent/base.py", line 50, in execute
    output, returncode = self.run_subprocess(
  File "/home/frappe/agent/repo/agent/base.py", line 103, in run_subprocess
    raise subprocess.CalledProcessError(
subprocess.CalledProcessError: Command 'docker exec -w /home/frappe/frappe-bench  bench-xxxxx-000xxxx-fxx-reg bench --site site.frappe.cloud migrate --skip-search-index --skip-failing' returned non-zero exit status 137.

it means that your server ran out of memory and should ideally be upgraded to ease the load on the server. To upgrade your dedicated server refer this guide