Trustsource

x402-powered verification APIs for AI agents — URL safety, email authentication, domain trust, SSL/TLS, security headers, robots.txt. Pay per use, no API keys, no accounts.

Quick Start

1. Install dependencies

npm install

2. Configure environment

cp .env.example .env

Open .env and set at minimum:

PAY_TO_ADDRESS=0xYourBaseWalletAddress

Leave everything else as-is to run on Base Sepolia testnet (no real money).

3. Run the server

npm run dev

You should see the startup banner at http://localhost:3000.

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Testing the x402 Flow

Free endpoints (no payment needed)

curl http://localhost:3000/
curl http://localhost:3000/health

Paid endpoint — what an unpaid agent sees

curl http://localhost:3000/trustscore?domain=example.com
# Returns HTTP 402 with payment instructions in the PAYMENT-REQUIRED header

Paid endpoint — bypass payment for local dev testing

The x402 testnet facilitator at https://x402.org/facilitator accepts test payments. To fully test the payment flow, use an x402 client with a funded testnet wallet.

Get Base Sepolia testnet ETH: https://sepolia.base.org/faucet
Get testnet USDC: https://faucet.circle.com (select Base Sepolia)

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Switching to Mainnet (Production)

1. In .env, change:

   NETWORK=eip155:8453
   FACILITATOR_URL=https://api.cdp.coinbase.com/platform/v2/x402
   CDP_API_KEY_ID=your-key-id
   CDP_API_KEY_SECRET=your-key-secret
   

2. Make sure your PAY_TO_ADDRESS Base wallet has some ETH for gas.

3. Your endpoints auto-list in the Bazaar/Agentic.Market after the first paid call clears.

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API Reference

GET /urlcheck

One composite CLEAR / REVIEW / BLOCK safety verdict on any URL, fusing domain trust, a live TLS check, and typosquat/lookalike detection.

Payment: 0.01 USDC per call (via x402)

Params:

• ?url=https://example.com — URL to vet
• ?domain=example.com — bare domain (alternative)

Response:

{
  "domain": "paypa1.com",
  "verdict": "BLOCK",
  "score": 12,
  "maxScore": 100,
  "reasons": ["possible lookalike of paypal.com (homoglyph_substitution, confidence 0.90)"],
  "signals": {
    "domainTrust": { "score": 12, "tier": "HIGH_RISK", "ageDays": 3, "newlyRegistered": true },
    "tls":         { "reachable": true, "valid": true, "tier": "VALID", "daysRemaining": 60 },
    "typosquat":   { "isLookalike": true, "nearestBrand": "paypal.com", "technique": "homoglyph_substitution", "confidence": 0.9 }
  },
  "meta": { "checkedAt": "...", "apiVersion": "1.0", "paidWith": "x402/USDC", "cached": false }
}

Verdicts: CLEAR (safe) · REVIEW (inspect before acting) · BLOCK (do not proceed)

---

GET /emailtrust

Email-authentication posture grade (SPF/DKIM/DMARC/BIMI/MX) — is this sender domain spoofable?

Payment: 0.003 USDC per call (via x402)

Params:

• ?domain=example.com — sender domain (or [email protected])

Response:

{
  "domain": "example.com",
  "grade": "C",
  "score": 45,
  "maxScore": 100,
  "spoofable": true,
  "spf":   { "present": true, "qualifier": "~all", "multiple": false },
  "dmarc": { "present": true, "policy": "none", "pct": 100, "rua": true },
  "dkim":  { "present": true, "selectorsFound": ["default"] },
  "bimi":  false,
  "mx":    ["mail.example.com"],
  "issues": ["dmarc_p_none_no_enforcement"],
  "meta": { "checkedAt": "...", "apiVersion": "1.0", "paidWith": "x402/USDC", "cached": false }
}

Grades: A/B = enforced, not spoofable · C/D = monitoring only, spoofable · F = no authentication

---

GET /trustscore

Returns a 0–100 trust score for any domain.

Payment: 0.003 USDC per call (via x402)

Params:

• ?domain=example.com — bare domain
• ?url=https://example.com/some/path — full URL (domain extracted)

Response:

{
  "domain": "example.com",
  "score": 80,
  "maxScore": 100,
  "tier": "TRUSTED",
  "breakdown": {
    "domainAge": 30,
    "tld": 20,
    "dnsPresence": 30,
    "registrar": 20
  },
  "details": {
    "age": { "days": 9720, "label": "established (5+ years)", "created": "...", "expires": "..." },
    "tld": ".com",
    "dns": { "hasARecord": true, "hasMxRecord": true, "mxRecords": ["mail.example.com"] },
    "registrar": "GoDaddy"
  },
  "meta": {
    "checkedAt": "2026-05-22T12:00:00.000Z",
    "apiVersion": "1.0",
    "paidWith": "x402/USDC"
  }
}

Tiers:

Score	Tier
75–100	TRUSTED
50–74	MODERATE
25–49	CAUTION
0–24	HIGH_RISK

---

Project Structure

trustsource/
├── src/
│   ├── server.ts          # Express app + x402 middleware, rate limiting, logging
│   ├── openapi.ts         # OpenAPI 3.1 spec served at /openapi.json
│   ├── lib/
│   │   ├── net-guard.ts   # Shared SSRF guard (private-IP checks, resolve + pin)
│   │   ├── domain.ts      # Shared domain extraction/validation
│   │   ├── cache.ts       # Shared in-memory TTL cache
│   │   ├── domain-trust.ts # Domain trust scoring (used by /trustscore + /urlcheck)
│   │   ├── tls-check.ts   # TLS handshake + cert scoring (used by /sslcheck + /urlcheck)
│   │   ├── typosquat.ts   # Lookalike/typosquat detection (used by /urlcheck)
│   │   └── mailauth.ts    # SPF/DKIM/DMARC/BIMI/MX analysis (used by /emailtrust)
│   └── routes/
│       ├── urlcheck.ts    # Composite CLEAR/REVIEW/BLOCK URL verdict
│       ├── emailtrust.ts  # Email-auth posture grade
│       ├── trustscore.ts  # WHOIS + DNS + TLD + registrar scoring
│       ├── sslcheck.ts    # Live TLS handshake + certificate scoring
│       ├── headers.ts     # HTTP security-header audit
│       └── robots.ts      # robots.txt + AI-bot policy detection
├── mcp-server/            # MCP server wrapping the six APIs as tools
├── public/                # Landing page
├── .env.example
├── .env                   # Your config (git-ignored)
├── package.json
└── tsconfig.json

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Roadmap

• TrustScore API — domain trust scoring
• SslCheck API — TLS/SSL certificate intelligence
• Headers API — HTTP security-header audit
• Robots API — robots.txt + AI-bot policy detection
• UrlCheck API — composite CLEAR/REVIEW/BLOCK URL safety verdict
• EmailTrust API — SPF/DKIM/DMARC/BIMI/MX spoofability grade
• OpenAPI spec at /openapi.json
• Bazaar / Agentic.Market discovery extension
• MCP server (trustsource-mcp) wrapping all six APIs
• /safefetch — injection-safe content firewall (flagship)
• /phishcheck — typosquat + Certificate-Transparency detection
• /kyb — official-registry business-identity verification
• ResearchOracle (reshaped) — verification / source-trust oracle