Jern Cloud docs

Look for bugs every Tuesday.

A schedule opens a session on the clock as the member who set it. This one asks for a bug hunt once a week, and the baseline keeps the answer small enough to review in a minute.

The policy

The demo repository's protected baseline, .jern/baseline.json, pinned by digest for the life of every session. Edits may touch src/ and tests/ only, at most four files and two hundred lines, never .jern/ or .github/. The test command runs without asking after every edit.

{
  "policy": {
    "edits_within": ["src/", "tests/"],
    "protected_paths": [".jern/", ".github/"],
    "max_files_edited": 4,
    "max_lines_changed": 200,
    "memory": "allow",
    "shell_allow": ["python3 -m unittest discover -s tests -t .", "python3"]
  },
  "environment": {
    "services": ["postgres:16"],
    "network_allow": ["docs.python.org"]
  },
  "test_command": "python3 -m unittest discover -s tests -t ."
}

The schedule

When	`30 15 * * 2` in `America/Toronto`: Tuesdays at 15:30.
Message	Look for bugs to fix
Cap	The trigger cap, 4,000,000 tokens per attempt; a schedule can lower it.

Set in the Automation section of the repository's page, by a member who can start sessions there. Triggers were on under Settings › Triggers, which a schedule needs.

What came back

Pull request 77, opened by the run that was due at 19:30 UTC. The agent read the source, ran the tests, found that fahrenheit_to_celsius dropped the 32-degree offset, and fixed it in one place: one file, one line added, two removed. The pull request's first line names the schedule and the time it was due.

Receipt row	What it said
Outcome	success, pull request ready
Policy	`.jern/baseline.json` digest `5a58da65014e`, repository baseline, pinned
Model	6 gateway calls
Tokens	32,363 in, 677 out; 14,434 counted toward the cap of 4,000,000
Estimated spend	$0.019 at list price
Files touched	`src/temperature.py` +1 −2; 1 of at most 4 files, 3 of at most 200 lines
Network	docs.python.org allowed; none contacted
Sandbox	private network namespace, loopback relays only, writes within the policy's paths

Why it is safe to leave running

Nothing merges. The pull request waits for a reviewer like any other, with the receipt as a check beside your CI. The blast radius means the worst a bad week can produce is a two-hundred-line pull request you close. The spend is on the usage report under the repository, in the column for scheduled work, and a cap per run bounds it. If the member who set the schedule leaves the workspace, the schedule stops with a refusal you are notified of.

Try it on your repository

Merge a setup pull request so the repository owns its baseline, or let a workspace profile govern it; see Policy.
Turn triggers on under Settings › Triggers and pick the model they run on.
In the Automation section of the repository's page, add a schedule: a day and time in your zone, and the message. "Look for bugs to fix" is enough; a more useful one names where to look.