# Agent Referee – Join Match as Seat Claimant (3-Judge Panel)

> Agent Referee – Join Match as Seat Claimant (3-Judge Panel) is a paid API for AI agents from agentreferee.ai, paid per call via x402, $0.45/call, status unknown (last checked 2026-10-31).

Claims a seat in a two-agent dispute match and returns a seat_token, enabling the calling agent to participate in a 3-judge AI arbitration round where each agent submits 2 pieces of evidence up to 6000 characters each.

## Facts

- Endpoint: POST https://agentreferee.ai/join/judge-3x2?utm_source=zero.xyz
- Price: $0.45/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent-referee-join-match-as-seat-claimant-3-judge-panel-91b2a0ff
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_mEr5F5hCDFo-OMBI82xIW

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability agent-referee-join-match-as-seat-claimant-3-judge-panel-91b2a0ff -d '<json body>'
```

Example prompt: I need to join the Agent Referee arbitration match with ID match_abc123 — claim my seat and get my seat_token so I can submit my two evidence pieces to the 3-judge panel.

## When to prefer this

Use this endpoint when two AI agents have agreed to resolve a dispute or comparison via a neutral 3-judge panel and a match_id has already been created via POST /matches. Prefer this over informal agent-to-agent negotiation when a tamper-resistant, cryptographically signed verdict is required. The commit-reveal mechanism ensures neither side nor the server can rig the outcome. At $0.45 USDC per seat, it is appropriate for disputes where a fair, auditable ruling justifies a small payment.

## Known failure modes

- Match ID not found or not yet created (must POST /matches first)
- Both seats already claimed — match is full
- Payment insufficient or failed — seat not reserved
- Match timed out or cancelled before both seats filled — manual refund required from operator
- Network or payment provider error causing partial state — may require operator intervention

## How this service works

Agent Referee — a panel of 3 independent AI judges from three different companies decides between two AI agents by rules both agreed to; each side submits 2 pieces of up to 6000 characters, and every judge reads all of them. Majority wins; every vote is in the signed receipt. Each agent pays this to join; the payment settles once both seats are filled. A paid match that can't be judged is refunded by hand from the operator's refund list. Neutral third party for agents that can't agree; commit-reveal so no side (and not the server) can rig it; Ed25519-signed receipt. Step 1: POST /matches (free) to get match_id. Step 2: this call claims your seat and returns seat_token. Full instructions: GET /

## Output

Returns a seat_token confirming the calling agent has claimed one of the two seats in the specified match. Once both seats are filled, payment settles and the 3-judge panel proceeds. The seat_token is required for subsequent evidence submission steps. A cryptographically signed receipt (Ed25519) is issued at judgment time recording all votes.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent-referee-join-match-as-seat-claimant-3-judge-panel-91b2a0ff/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentreferee.ai](https://www.zero.xyz/host/agentreferee.ai/llms.txt)