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This wizard sets up pay-per-call monetization on one of your API endpoints using the x402 protocol. When an agent hits a protected endpoint, your API responds 402 Payment Required; the agent pays, retries with proof, and gets the real response. Dashboard path: app.getsly.ai/dashboard/onboarding/wizard/api-monetization Estimated time: ~10 minutes

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Who this is for

  • SaaS APIs — pay-per-query or per-operation billing
  • AI / ML inference — per-prompt, per-image, per-generation
  • Data providers — per-record, per-query
  • Any endpoint where sign-up-free, machine-initiated payment is valuable

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What you’ll have when done

  • A receiving wallet collecting x402 payments (USDC, on low-fee network by default)
  • A test-funded wallet for sandbox verification
  • Your API endpoint registered with x402 pricing
  • Price-per-request rules applied
  • A confirmed end-to-end test payment

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Steps

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1. Create your receiving wallet (required, ~2 min)

Sly creates a dedicated wallet that will collect payments from API consumers. Wizard asks you:
  • Wallet name (e.g. x402-receipts)
  • Network — Solana is recommended for lowest fees; Base if you prefer Ethereum L2
API equivalent: 
curl -X POST https://sandbox.getsly.ai/v1/wallets \
  -H "Authorization: Bearer $SLY_API_KEY" \
  -d '{
    "owner_type": "account",
    "owner_id": "acc_...",
    "currency": "USDC",
    "network": "solana-devnet"
  }'

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2. Fund your wallet (optional, ~3 min)

Add initial USDC so you can test flows that reverse (refunds, disputes). In sandbox this is free (faucet); in live it uses card / Apple Pay / Google Pay / bank. If you skip: the wallet starts at zero balance. You can fund anytime from the dashboard. API equivalent (sandbox faucet): 
curl -X POST https://sandbox.getsly.ai/v1/wallets/wal_.../fund \
  -H "Authorization: Bearer $SLY_API_KEY" \
  -d '{ "amount": "100.00", "currency": "USDC" }'

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3. Register your API endpoint (required, ~3 min)

Tell Sly which API endpoint accepts x402 payments. Wizard asks you:
  • Your API base URL (e.g. https://api.yourcompany.com)
  • The specific path + method you’re protecting (POST /v1/infer)
  • Name + description (for your dashboard)
Sly generates an x402 gateway URL for this endpoint. Agents call the gateway; Sly handles the 402 dance + proof verification; the real request reaches your origin once payment is confirmed. API equivalent: 
curl -X POST https://sandbox.getsly.ai/v1/x402/endpoints \
  -H "Authorization: Bearer $SLY_API_KEY" \
  -d '{
    "name": "Inference API",
    "path": "/v1/infer",
    "method": "POST",
    "accountId": "acc_...",
    "basePrice": 0.05,
    "currency": "USDC",
    "network": "solana-mainnet"
  }'

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4. Configure pricing (optional, ~2 min)

Set price per request. Common ranges:
  • $0.001 — simple lookups, cheap compute
  • 0.01−0.01-0.10 — AI / ML inference, heavier operations
  • $0.10+ — expensive compute, premium data
You can also set volume discounts — reduced per-call price after an agent has made N calls. Useful for power-user pricing. If you skip: default pricing of $0.01 per request applies. API equivalent (volume discounts): 
curl -X PATCH https://sandbox.getsly.ai/v1/x402/endpoints/epd_... \
  -H "Authorization: Bearer $SLY_API_KEY" \
  -d '{
    "basePrice": 0.05,
    "volumeDiscounts": [
      { "threshold": 100,  "priceMultiplier": 0.8 },
      { "threshold": 1000, "priceMultiplier": 0.5 }
    ]
  }'

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5. Test your integration (optional, ~3 min)

Sly simulates an agent making a paid API call using testnet funds, showing the full 402 → pay → retry → 200 flow. If you skip: you can test anytime from the dashboard → Endpoints → [endpoint] → Test.

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After the wizard

Share your gateway URL with API consumers. They call it like any HTTP endpoint — agents using the Sly SDK auto-handle the 402 → pay → retry cycle. See x402 client usage. Monitor revenue. Dashboard → Endpoints → [endpoint] shows total calls, unique payers, revenue by window, and top payers. Go live. When ready, flip to a pk_live_* key and your gateway serves real x402 traffic on mainnet.

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What to configure next

  • Webhook events — subscribe to x402.payment.completed to get notified per payment
  • Rate limits — in addition to x402 gating, apply call rate limits to prevent abuse
  • x402 bridge — if you want to accept USDC but settle in fiat via Circle

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Troubleshooting

Check the endpoint status is active (dashboard → Endpoints). Check the target URL in the x402 registration resolves and returns the real response on direct call — the gateway proxies to your origin, it doesn’t replace it.
The gateway only forwards to your origin after payment verification. Confirm your origin allows Sly’s IP range (docs → IP allowlist) and that it’s not rejecting requests with the payment proof header.
Usually means the agent’s wallet is underfunded. The Sly SDK handles this cleanly; raw-HTTP agents must implement the 402 dance themselves.