require-rank

Gate your AI agent by the caller's AgentRank.

Verify-before-pay is the payer asking "is this safe to pay." require-rank is the provider asking "does this caller have a rank before I do work for it." Wrap your MCP tools (or any handler): ranked, settlement-backed callers are served; ghosts and unranked callers are refused or surcharged — and the refusal tells them how to get ranked, which sends them to AgentRank to claim and settle.

Every check is a live query, so your rank requirement runs in the hot path of real work. Zero deps.

Install

npm install require-rank

Wrap an MCP tool

import { requireRank } from "require-rank";

server.tool(
  "expensive_inference",
  schema,
  requireRank(handler, {
    minScore: 500,          // require AgentRank >= 500
    requireVerified: true,  // caller must be settlement-verified
    onFail: "refuse",       // "refuse" | "surcharge" | "allow"
    callerFrom: (args) => args.caller,   // how to read the caller wallet/domain from the call
  })
);

A caller below the bar gets an MCP result carrying the verdict and a claim CTA (agentrank.info) instead of your tool running. A ranked caller passes through, and your handler receives extra.agentrank (the caller's score and settlement) so you can price or personalize.

Just the gate

import { RankGate } from "require-rank";

const gate = new RankGate({ minScore: 500 });
const d = await gate.check("0xCallerWallet");   // wallet or domain
// { allow: true, rank: { score: 870, verified: true }, reason: "ranked 870/1000", surcharge: 1 }

Rank-priced x402

import { rankPrice } from "require-rank";
const amount = rankPrice(0.01, decision);   // ranked pays base; unranked pays the surcharge multiple

No-install option

Don't want a dependency? Call the hosted gate directly:

GET https://api.agentrank.info/gate/{caller}?min=500&verified=1&onfail=refuse
-> { allow, score, surcharge, reason, cta }

Or over MCP: the gate_caller tool at https://api.agentrank.info/mcp.

Why caller rank is sound

AgentRank ranks by real on-chain settlement weighted by payer reputation (PageRank on the USDC payment graph, de-noised, sybil-tested). A caller is verified only if reputable payers have sent it real money — which a ghost or sybil cannot fake. In an x402 flow the payment itself proves the caller's wallet; for pure MCP, treat the rank as the caller's claimed standing and require a signature or a payment to harden it. Method: https://github.com/andysalvo/agentrank.

MIT. Built by Crest Deployment Systems LLC.