Pay - Naïve

POST

users

:user_id

payments

pay

curl -X POST https://api.usenaive.ai/v1/users/user-uuid-1/payments/pay \
  -H "Authorization: Bearer nv_sk_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://api.example.com/report",
    "max_amount": "0.50"
  }'

{
  "status": 200,
  "body": "{\"report\":\"...\"}",
  "paid": true,
  "receipt": {
    "id": "receipt-uuid-1",
    "companyId": "company-uuid-1",
    "tenantUserId": "user-uuid-1",
    "direction": "buy",
    "origin": "https://api.example.com",
    "route": null,
    "payTo": "0xfeedfacecafebeef0123456789abcdef01234567",
    "amount": "0.50",
    "asset": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913",
    "network": "eip155:8453",
    "scheme": "exact",
    "txHash": "0x8f2c1de4a90b7356e1c2f8a94b0d6e7351829af0cb3d47e5a61b9c8d2f3e4a5b",
    "nonce": "0x2b7e151628aed2a6abf7158809cf4f3c762e7160f38b4da56a784d9045190cfe",
    "settleResponseB64": "eyJzdWNjZXNzIjp0cnVlLCJ0cmFuc2FjdGlvbiI6IjB4OGYyYzFkZTQifQ==",
    "actionId": null,
    "ts": "2026-07-16T12:00:00Z"
  }
}

Fetches an x402 resource, paying for it from the agent’s wallet if it demands payment. Returns the resource body plus a receipt.

Sensitive — this spends real USDC. Use Quote first to learn the price with zero side effects.

How it works

Fetch the URL.
Not a 402? Return the response — paid: false, no receipt, nothing spent.
Decode the requirements and select one under policy: exact scheme, USDC, an allowed network, at or under the effective cap.
Check balance and dailyBudget, then emit payment.requested.
Sign a USDC payment in the custody plane, which re-enforces perTxMax at signing time.
Retry the request once with the payment attached.
Hard stop — persist the receipt and emit payment.settled. A failure after signing is never retried a second time.

Spend control — no approval workflow

There is deliberately no approval queue on this endpoint, unlike cards. What bounds a payment:

Control	Where it is enforced
Wallet balance	An agent cannot spend what isn’t there
`perTxMax`	Twice — at runtime, and as a static custody-plane policy at signing time, which survives a compromised runtime
`dailyBudget` (optional)	A rolling per-UTC-day runtime counter
`max_amount`	A per-call ceiling on this one payment

The effective per-payment cap is min(max_amount, wallet perTxMax).

Request Body

Parameter	Type	Required	Description
`url`	string	Yes	The x402 resource URL to pay for and fetch
`init`	object	No	Fetch init — `method`, `headers`, `body`
`max_amount`	string	No	Per-call ceiling as a decimal USDC string, e.g. `"0.50"` — not atomic units. `maxAmount` is accepted as an alias

curl -X POST https://api.usenaive.ai/v1/users/user-uuid-1/payments/pay \
  -H "Authorization: Bearer nv_sk_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://api.example.com/report",
    "max_amount": "0.50"
  }'

{
  "status": 200,
  "body": "{\"report\":\"...\"}",
  "paid": true,
  "receipt": {
    "id": "receipt-uuid-1",
    "companyId": "company-uuid-1",
    "tenantUserId": "user-uuid-1",
    "direction": "buy",
    "origin": "https://api.example.com",
    "route": null,
    "payTo": "0xfeedfacecafebeef0123456789abcdef01234567",
    "amount": "0.50",
    "asset": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913",
    "network": "eip155:8453",
    "scheme": "exact",
    "txHash": "0x8f2c1de4a90b7356e1c2f8a94b0d6e7351829af0cb3d47e5a61b9c8d2f3e4a5b",
    "nonce": "0x2b7e151628aed2a6abf7158809cf4f3c762e7160f38b4da56a784d9045190cfe",
    "settleResponseB64": "eyJzdWNjZXNzIjp0cnVlLCJ0cmFuc2FjdGlvbiI6IjB4OGYyYzFkZTQifQ==",
    "actionId": null,
    "ts": "2026-07-16T12:00:00Z"
  }
}

A resource that isn’t paywalled returns paid: false and receipt: null — nothing was spent. The receipt’s amount is a decimal USDC string, and settleResponseB64 is the raw base64 PAYMENT-RESPONSE envelope: the onchain-verifiable audit artifact. Receipts are booked idempotently on (direction, origin, nonce), so a replay returns the existing row and books nothing twice.

Errors

Status	Code	When
400	`invalid_input`	`url` is required
400	`wallet_not_configured`	No wallet for this agent — create one before paying
402	`payment_rejected`	The payment was refused. See `error.reason` below
403	`forbidden`	The Account Kit has not enabled the `payments` primitive

`payment_rejected` reasons

`error.reason`	Meaning
`no_acceptable_requirements`	The 402 advertised no requirements, or had no `PAYMENT-REQUIRED` header
`unsupported_scheme`	No `exact`-scheme requirement
`unsupported_network`	No requirement on an allowed network
`unsupported_asset`	No USDC requirement
`over_per_tx_max`	Every requirement exceeds the effective cap
`insufficient_balance`	The wallet balance is below the payment amount
`daily_budget_exhausted`	The payment would exceed `dailyBudget`
`settlement_failed`	The resource rejected the signed payment. Hard stop — not retried

CLI

naive use <user-id>
naive payments pay --url https://api.example.com/report --max-amount 0.50

MCP

Tool: naive_payments_pay

{
  "url": "https://api.example.com/report",
  "max_amount": "0.50"
}

curl -X POST https://api.usenaive.ai/v1/users/user-uuid-1/payments/pay \
  -H "Authorization: Bearer nv_sk_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://api.example.com/report",
    "max_amount": "0.50"
  }'

{
  "status": 200,
  "body": "{\"report\":\"...\"}",
  "paid": true,
  "receipt": {
    "id": "receipt-uuid-1",
    "companyId": "company-uuid-1",
    "tenantUserId": "user-uuid-1",
    "direction": "buy",
    "origin": "https://api.example.com",
    "route": null,
    "payTo": "0xfeedfacecafebeef0123456789abcdef01234567",
    "amount": "0.50",
    "asset": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913",
    "network": "eip155:8453",
    "scheme": "exact",
    "txHash": "0x8f2c1de4a90b7356e1c2f8a94b0d6e7351829af0cb3d47e5a61b9c8d2f3e4a5b",
    "nonce": "0x2b7e151628aed2a6abf7158809cf4f3c762e7160f38b4da56a784d9045190cfe",
    "settleResponseB64": "eyJzdWNjZXNzIjp0cnVlLCJ0cmFuc2FjdGlvbiI6IjB4OGYyYzFkZTQifQ==",
    "actionId": null,
    "ts": "2026-07-16T12:00:00Z"
  }
}

​How it works

​Spend control — no approval workflow

​Request Body

​Errors

​payment_rejected reasons

​CLI

​MCP

How it works

Spend control — no approval workflow

Request Body

Errors

`payment_rejected` reasons

CLI

MCP