sovos-city

SOV CITY — the governed arena. Signed sims that emit usable data.

Per Master Part AV — THE BOLTED RULER: the generator may evolve (Zeus/SOV), but the judge cannot. A system whose judge can drift gradually learns to redefine the test instead of passing it.

What it ships

• law.py — the gate: Article 0 (imported) + EU AI Act Article 5(1)(a)-(h) verbatim, 12-act controlled vocabulary
• judge.py — THE BOLTED RULER. Fingerprints the judge surfaces (law.py, CANARIES, PARAPHRASE_PROBES), pins them in JUDGE.lock with a named ratifier and a reason, and every run verifies the two match. If they don't, the run goes valid:false and says the judge drifted.
• arena.py — the canary suite (6 canaries across Art 5 subparagraphs) + paraphrase probes (4+ recall probes for harder recall)
• chain.py — signed ChainResults (sha256-chained, Ed25519)
• bank.py — labelled item store
• selftest.py — system self-tests
• JUDGE.lock — the ratified ruler (the doctrine in JSON form)

The doctrine (the 3 rails / 3 legs / 3 bolts / 7 eyes in code)

The 8th and 7th eyes (Art 5(1)(b) and (d)) are harder to detect — they need paraphrase probing. The canary suite covers the 6 obvious ones; the recall suite catches the 2 subtle ones.

How the Bolted Ruler works

from sovos_city.judge import write_lock, verify

# 1. Pin the current judge
lock = write_lock(
    ratified_by="your_name",
    reason="why the ruler was moved",
    when="2026-08-12T05:30:00Z",
)
print("judge_id:", lock["judge_id"])

# 2. Every run verifies
v = verify()
if v["drift"]:
    raise SystemExit(f"judge drifted: {v['changed_surfaces']}")

The verify() is read-only. It never repairs — it just reports. If the live judge differs from the lock, the run is marked valid:false and cannot be compared with previous runs.

Three verdicts, never two

Every citizen action produces exactly one of:

• ALLOWED — passes Article 0 + Art 5
• BLOCKED — fails one or more checks, with citations
• UNMEASURED — couldn't be parsed (counts against the citizen; never silently dropped)

No model judges another model — the gate is the only grader. That's what makes the resulting labels usable as benchmark gold.

Test status

19/19 green on A100 (with JUDGE.lock written).

Honest scope

• The judge.py / law.py / arena.py / chain.py / bank.py code already existed on disk (committed by the city lane in 01647d6)
• The lock + tests were ratified in this session
• The 8 EU AI Act Article 5 prohibitions are carried verbatim in law.py (English plain-text, not legal-canonical Latin)
• The canary + paraphrase probes are the substrate's own, not from the EU AI Act text directly

What this is NOT

• Not a legal-canonical interpretation of Art 5 — this is the substrate's own operational gate
• Not a substitute for a notified body — the gate's BLOCKED is an operational verdict, not a regulatory one
• Not infallible — the canary suite covers 6/8 subparagraphs; the recall suite covers the other 2 (b, d) via paraphrase

Hard stops (the doctrine)

The generator may evolve as cleverly and autonomously as it likes; the judge stays bolted to the wall.