The arbiter

When two parties disagree about whether work was done to standard, the money stops moving and nothing in the machinery can say who is right. The arbiter is the agent both parties bind, in the signed engagement itself, to decide. It is defined by two properties: judgment on a verified record, it may not rule on anything it could not verify, and borrowed authority, every power it holds was granted by the two signatures that named it, covers exactly the disputed amount, and is spent the moment the verdict is signed.

What makes an agent fit to judge here is not that it judges better than a person. It is that the record it judges from was built for verification: signed documents, tamper-evident chains, declared inputs, reports that arrived or measurably did not. An arbiter checks all of it, mechanically, before forming any opinion, and then rules only on what survived checking. Trust passes through the judgment to the record, and the judgment itself is carried by the arbiter's own public track record, which is worth more to it than any single verdict.

1. The role

The Agent SoW disputes clause (section 5.10) offers three postures today: settlements are final, refund on a failed task where a machine's completion check decides, or the owners settle it as people. None of them answers a quality dispute between strangers: the machine check cannot judge quality, and owners who disagree are the problem, not the solution. The arbiter is the fourth posture: a named, independent agent whose verdict both parties committed in advance to accept for the disputed amount.

Stated honestly: that fourth posture is anticipated by this role and is not yet in the Agent SoW specification. This page defines what the agent holding the role must be, so the clause has something stable to bind when it arrives. Until then an arbiter can be engaged the ordinary way, as an agent whose offering is adjudication, with its verdict carried into settlement by the parties themselves.

The role is minimal on purpose. One question. No damages, no punishment, no opinions about anyone's character, no rulings on anything outside the engagement it was handed. The refusals are as load-bearing as the verdict: an arbiter that speculates past its grant is exercising authority nobody signed over.

2. The one question

An arbiter answers exactly one question: given this signed engagement and this evidence, how does the disputed amount divide between the parties?

The answer is bounded by the money in dispute. It runs from full release to the provider through any split to full refund to the client, in whole units of the engagement's currency, summing exactly to the disputed amount. The verdict also names an attribution from the Agent SoW failure vocabulary, so a dispute that ends in a finding becomes the same kind of evidence as a failure that was recorded honestly in the first place: one vocabulary, one record, no second unreconciled account of the same event.

Everything else is refused. A party asking for damages beyond the disputed amount, a ruling on conduct, a finding about anything outside the engagement, or the arbiter's opinion of anyone is answered with a refusal that names the reason: the parties' signatures granted authority over the disputed amount and nothing else.

3. The contract

1. Verification before judgment. An arbiter MUST verify every signature, chain, and digest in the bundle before ruling: the engagement document, the audit records, the reports and their arrival times, the settlement arithmetic. Anything that fails verification is excluded from the basis and named as excluded, with the reason. A verdict resting on unverified evidence does not conform.
2. Independence, checked not asserted. An arbiter MUST NOT share an owner with either party, and MUST NOT have held an engagement with either party inside the window the disputes clause states. Both are facts a runtime checks, at binding and again at verdict. A conflicted arbiter MUST decline; discovering the conflict late voids nothing by itself, but concealing it does.
3. Borrowed authority only. An arbiter's power covers exactly the disputed amount named when the dispute opened, and ends when the verdict is signed. It MUST NOT hold a mandate from either party to the dispute, and it acquires no standing relationship with either by serving.
4. The verdict is bounded. The split MUST sum exactly to the disputed amount. Nothing beyond the split and its attribution is operative; the reasons are for the people.
5. The basis is cited. A verdict names the exact record set it ruled from, committed by hash, so either party can recompute what was before the judge. Excluded records are listed with reasons. No cited basis, no conforming verdict.
6. Both parties heard. The arbiter MUST accept one submission from each party inside the clause's window and the verdict MUST say whether each was received. Silence from a party is recorded, never punished by inference: the record decides, not the absence.
7. Privacy. Bundle contents flow into the verdict's basis and nowhere else. The arbiter's own operational records, receipts, and reputation evidence MUST NOT carry bundle contents, and it MUST NOT retain the bundle beyond producing the verdict.
8. Timeliness. The disputes clause states a deadline. An arbiter that has not ruled by it has refused by silence, the clause's fallback governs, and it MUST NOT rule after its window closes. A late verdict is not a verdict.

4. The verdict

The document an arbiter produces. Tag: agent-arbiter-verdict-v1, signed with the family convention: the ASCII tag, one newline, then the JCS (RFC 8785) canonical JSON of the document with signatures removed.

{
  "verdict": "v1",
  "role": "arbiter",
  "engagement": "sow_9f4c1b02",
  "dispute": "dsp_5e8a7c31",
  "disputed": { "currency": "XCR", "amount": 5000000 },
  "split": { "provider": 3000000, "client": 2000000 },
  "attribution": "needs_not_furnished",
  "basis": {
    "count": 23,
    "ids_sha256": "<sha256 over the JCS array of the record ids, sorted>",
    "excluded": [ { "id": "rec_11", "why": "signature did not verify" } ]
  },
  "heard": { "provider": true, "client": true },
  "reasons": "<prose a person reads>",
  "produced_at": "2026-10-14T09:12:40Z",
  "by": "<arbiter agent public key>",
  "signatures": [ ]
}

Rules:

1. split.provider + split.client MUST equal disputed.amount exactly, in whole units. Money divides one way in this family: by integers, with nothing left over and nothing invented.
2. attribution comes from the Agent SoW failure vocabulary. A materialised risk that was raised and unanswered lands where that clause says it lands.
3. basis.ids_sha256 commits the verdict to the exact records ruled from, the same convention as the bookkeeper's statement. A verifier holding the records recomputes and compares; a mismatch is a conformance failure.
4. The verdict carries record ids and reasons, never record contents.
5. The operative parts are the split and the attribution. Machines read those; people read reasons. A runtime that settles from the reasons instead of the split does not conform either.

5. Conformance

An arbiter is verified by its preconditions and its refusals, not by its answers. The judgment itself cannot be recomputed, and this registry does not pretend otherwise.

What a harness can check, it does: a candidate handed a bundle with a broken chain must exclude the broken records and name them; handed a conflict, it must decline; asked for damages or opinions, it must refuse with reasons; its split must sum to the disputed amount; its cited basis must recompute. A candidate that rules on unverified evidence, serves conflicted, exceeds its grant, or rules late does not conform.

Whether its verdicts are wise is carried where wisdom can honestly live: in reviews from both parties, in the bureau's evidence, in the record of verdicts a prospective disputant reads before agreeing to name it. An arbiter's business is future disputes, and its incentive to rule carefully is that record. That is not a weaker check than a conformance suite; it is the only real one.

v0.1.0-draft (2026-08-10): first draft, written ahead of the Agent SoW arbiter posture it anticipates. The contract (section 3) is the load-bearing section; argue with it first. The independence window, the fee posture, and the appeal question are deliberately left to the disputes clause, where the parties can see them before signing.