v0.1.0 — exit 0 is not evidence

Your scheduled job says exit 0. Prove it did the work. First tagged release.

Three small checks, no server, no dependencies, no account. They replace a job's self-report with evidence.

What is in v0.1.0

check	question it answers	catches
freshness	is the job's real output young enough?	exit 0 while the artifact rots
wrap	did this run actually change anything?	exit 0 with no work done
rollout	is the fix on every box, read back as a fact?	"rolled out" that never landed

All three speak one exit-code contract, implemented once in verified_ops/contract.py, designed so that a dead checker cannot look like a clean result — the specific trap being that exit 1 means "I found a problem" in most checkers and is what Python prints when the checker itself dies, so a crash gets painted the colour of a routine finding.

Why these three

Each is a failure that happened to us first, on a live agent fleet:

• a nightly artifact cold for two weeks behind a green heartbeat — the job fired every night and produced nothing;
• a checker crashing every night while the board showed a routine finding;
• a keyboard fix that sat undelivered on one box for twelve days after being "rolled out", because an offline box, a lagging box and a healthy box are all equally quiet.

The rule it lives by

A check with no mutant that makes it fail measures nothing. Every state in selftest.py is produced by planting the actual failure — a backdated file, an empty rewrite, a verify that only exits 0, a job that no-ops, a checker that crashes — and demanding both the right state and the right exit code. python3 selftest.py prints 44 checks, 0 failed.

Seven holes in this release were found by two external review rails before publication, not after.

Requirements

Python 3.8+, standard library only. CI: Ubuntu / macOS / Windows × 3.9 / 3.11 / 3.13.

git clone https://github.com/Palo-Alto-AI-Research-Lab/verified-ops-starter
cd verified-ops-starter && python3 selftest.py

Scope, stated plainly

This sits next to heartbeat monitoring (healthchecks.io, cronitor, dead-man switches), which answers did it fire? — a different and genuinely useful question. This kit answers did the work land?

What's next

A parity check that catches a box drifting silently over days, read-back adapters beyond the shell (HTTP, SQL), and a human-readable report. Not planned, deliberately: a server, a daemon, a dashboard, an account.

Every noticeable change ships as its own release, so this feed is the record of what the kit can actually prove.

Full Changelog: https://github.com/Palo-Alto-AI-Research-Lab/verified-ops-starter/commits/v0.1.0