ccheez34/agent-referee-mcp

Let any MCP-capable agent use Agent Referee: a neutral tie-breaker between agents from different owners, and sealed review of one agent's own work, with Ed25519-signed receipts.
Works with Claude Desktop, Claude Code, Cursor, and any other client that runs MCP servers over stdio. The free tools need no wallet and no account.
| Tool | What it does | Cost |
| demomatch | Runs a complete tie-break in one call, playing both seats, so you can see how it works. | Free |
| tiebreak | Settles a deadlock with another agent. Both agents call it with the same key and settings; neither side nor the service can steer the result. | Free demo for now (paid tiers next) |
| sealedreview | Independent AI reviewers check your agent's output against its task, and return a verdict plus a signed receipt you can hand to whoever receives the work. | Free: 3 reviews and 1 review-3 a day per address (no wallet). Then $0.05, or $0.20 for review-3 (three reviewers from three AI companies) |
| verifyreceipt | Checks any Agent Referee receipt offline against the pinned signing key. Pass the task and output to confirm a review is about exactly that work. | Free |
| savedreceipts | Lists the review receipts this server saved on your machine, and today's spend. | Free |
## Set it up
You need Node.js 18 or newer.
### Claude Desktop
Open Settings → Developer → Edit Config and add this to claudedesktopconfig.json, then restart Claude Desktop:
json
"mcpServers": {
"agent-referee": {
"command": "npx",
"args": ["-y", "agent-referee-mcp"]
On Windows, if Claude Desktop can't start it, use "command": "cmd" and "args": ["/c", "npx", "-y", "agent-referee-mcp"].
### Claude Code
bash
claude mcp add agent-referee -- npx -y agent-referee-mcp
On Windows: claude mcp add agent-referee -- cmd /c npx -y agent-referee-mcp
### Grok CLI (Grok Build)
bash
grok mcp add agent-referee -- npx -y agent-referee-mcp
Restart the Grok session so it loads the server. The first call can take a few extra seconds while npx downloads the package.
### Other MCP clients
Any client that runs local (stdio) MCP servers works the same way: the command is npx with the arguments -y agent-referee-mcp.
### Try it
Ask your agent: "Use demomatch to run a free Agent Referee demo." It returns the winner, the signed receipt (marked demo), and the checks: the signature, each side's own seed, and the math.
## Free sealed reviews
With no wallet set up, sealedreview uses the free daily allowance: 3 single-reviewer reviews and 1 review-3 per day from each address (IP address, or /64 block for IPv6), reset at 00:00 UTC. The operator pays for these, and one daily budget is shared by everyone, so free reviews can run out before the day ends. When they do, the tool says so.
Free receipts are signed exactly like paid ones and say "funding": "free", with no payer.
A busy service or a failed reviewer doesn't use up a free review.
With a wallet set up, reviews are paid unless the agent passes free: true.
## Paid sealed review: add a wallet
sealedreview pays per review in USDC on Base over x402, from a wallet you configure. It's charged only if the review completes.
1. Create a dedicated wallet for your agent and put only a few dollars of USDC on Base in it. Never use your main wallet.