Skip to main content

Documentation Index

Fetch the complete documentation index at: https://docs.nevermined.app/llms.txt

Use this file to discover all available pages before exploring further.

Accept credit cards in USD or EUR, with no crypto wallet required. Fiat payments are the fastest path to mainstream adoption. Your users can start paying with a card they already have, either through Stripe Checkout (one-time plan purchase) or by enrolling their card via Nevermined Pay for autonomous agent charging.

​
When to Use Fiat Payments

Enterprise Adoption

Organizations that already pay for SaaS with corporate cards can onboard without touching crypto.

Mainstream Users

No wallet setup, no token bridging. Users pay with the card in their pocket.

Regulatory Compliance

Fiat-denominated billing simplifies accounting, invoicing, and compliance for businesses.

Instant Onboarding

Users go from discovery to first API call in seconds. No wallet funding step required.

​
Fiat Payment Scenarios

Nevermined supports fiat payments in two scenarios:
  • Human-to-Agent: A user visits the Nevermined App checkout page and purchases a plan with their credit card. This is the simplest flow for onboarding new customers.
  • Agent-to-Agent: An agent owner enrolls a credit card via Nevermined Pay (Visa, Stripe, or Braintree) and creates a spending delegation. The agent can then make autonomous payments on behalf of the owner, charging the card per request within the defined limits.

​
Pay-per-request or a bundle of credits

Nevermined offers two distinct fiat payment flows depending on whether you want upfront plan purchases or per-request charging.

Plan Purchase

One-time or recurring payment via Stripe Checkout. The user buys a plan, a webhook confirms the payment, and credits are minted on-chain. Best for human users who want a familiar checkout experience.

Card Delegation via Nevermined Pay

Per-request charging via the x402 protocol. The user enrolls a Visa, Stripe, or Braintree card, creates a spending delegation with limits, and the agent charges it for each request. Best for automated workflows and agent-to-agent payments.

​
Human-to-Agent Purchase Flow

The simplest way to accept fiat. Users complete a standard Stripe Checkout session, and Nevermined handles the rest.
1

Select a plan

The user browses available plans in the Nevermined App or your custom UI and selects one priced in fiat.
2

Redirect to Stripe Checkout

Nevermined creates a Stripe Checkout session and redirects the user to complete payment with their card.
3

Payment completes

Stripe processes the charge. For recurring plans, Stripe manages subsequent billing automatically.
4

Webhook confirms payment

Nevermined receives a webhook from Stripe confirming the successful payment.
5

Credits minted on-chain

The corresponding credits are minted to the subscriber’s account, and they can immediately start using the agent.
Both one-time and recurring plan purchases are supported. For recurring plans, Stripe handles rebilling and Nevermined mints fresh credits each billing cycle.

​
Agent-to-Agent Purchase Flow (Nevermined Pay)

Fully autonomous agent-to-agent payments in fiat are enabled through Nevermined Pay. This allows an agent to charge a user’s card on-demand, without the user needing to pre-purchase credits. Instead of buying credits upfront, the user enrolls a card and creates a spending delegation with defined limits. NVM Pay supports three card enrollment providers, all consumed through the unified nvm:card-delegation x402 scheme:
  • Visa — Cards tokenized as Visa Agentic Tokens via the VGS Credential Management Platform. Each delegation requires a per-delegation WebAuthn/passkey device-binding ceremony enforced by Visa VTS. Settlement runs through Stripe Connect.
  • Stripe — Cards captured via VGS Collect, confirmed against a Stripe SetupIntent, vaulted as pm_…. Settlement runs through Stripe PaymentIntents.
  • Braintree — Cards captured via Braintree Drop-in, vaulted as a paymentMethodToken. Settlement runs through transaction.sale against an OAuth-connected seller merchant account.
1

Card Enrollment

The user enrolls a card via the Nevermined Pay dashboard. Card data is tokenized by the provider (VGS Collect for Visa and Stripe; Braintree Drop-in for Braintree) and NVM Pay never stores raw card numbers. See Card Enrollment for the full flow.
2

Create a spending delegation

The user creates a delegation that defines spending limits: lifetime amount ceiling, max transactions, and duration. Optionally, they can link it to a specific API key for automatic selection. Visa delegations require an additional per-delegation passkey approval (browser-only). See Delegations.
3

Agent requests payment

When the agent makes a request, it calls the NVM Pay API with its NVM API key. NVM Pay resolves the right delegation and generates an x402 payment token.
4

Verify and settle

The resource server verifies the payment token, executes the workload, then settles. NVM Pay charges the enrolled card and records the transaction.
Card delegation is what enables fiat-based agent-to-agent payments. An agent owner enrolls their card and sets spending limits, and the agent can autonomously pay for services from other agents, all settled in fiat. See the NVM Pay FAQ for common questions.
Visa delegation creation is browser-only because of the WebAuthn/passkey device-binding ceremony. The SDK can consume an existing Visa delegation (by passing its delegationId to DelegationConfig) but cannot create one programmatically.

​
Permission Model

Delegations enforce strict spending limits to protect the cardholder. All three networks share the same controls:
LimitFieldNotes
Lifetime spending limitspendingLimitCentsCumulative cap across all charges on the delegation
Max transactionsmaxTransactionsOptional; omit the field to allow unlimited transactions
DurationdurationSecsSeconds from createdAt
Plan bindingplanIdRequired for Visa (Trusted Agent Protocol)
Device bindingconsumerPrompt + assuranceDataVisa-only; produced by the in-browser WebAuthn ceremony
A delegation moves through a simple lifecycle:
StateMeaning
ActiveValid and can be used for charges
ExhaustedThe spending limit or transaction count has been reached
ExpiredThe expiration date has passed
RevokedThe cardholder manually revoked it
Once a delegation leaves the Active state, a new one must be created to continue charging. See Delegations for full details on spending controls and the Delegation Selection algorithm.

​
Security and PCI Compliance

Card data never reaches Nevermined servers. Depending on the provider:
  • Visa path — PAN is captured in a VGS Collect iframe and posted directly to the VGS Credential Management Platform via VGS-internal routing. CMP issues a Visa Agentic Token (vat_…) that replaces the PAN. Each delegation is bound to the cardholder’s device via a WebAuthn/passkey ceremony enforced by Visa VTS, producing a single-use assuranceData blob.
  • Stripe path — PAN is captured in a VGS Collect iframe and forwarded directly to Stripe to confirm a SetupIntent. Stripe vaults the card as a pm_… PaymentMethod.
  • Braintree path — PAN is captured by the Braintree Drop-in / hosted fields, which post directly to Braintree and return a single-use nonce. The facilitator vaults the nonce as a permanent paymentMethodToken.
Nevermined is PCI compliant (PCI SAQ D level) and holds ISO 27001 and SOC 2 Type II certifications. Strong Customer Authentication is enforced per-delegation for Visa (WebAuthn/passkey, with email OTP fallback) and at enrollment for Stripe and Braintree (3DS where the issuer requires it). See the NVM Pay FAQ for full security details.

​
Revenue Routing

When a user pays with a card, Nevermined routes the revenue to the builder’s connected account on the appropriate PSP:
  • Stripe & Visa — via Stripe Connect (transfer_data.destination). Fees are deducted automatically before the payout reaches the builder. Visa delegations always settle through the seller’s Stripe Connect account.
  • Braintree — via two transaction.sale calls: one against the platform’s per-currency merchantAccountId for the platform fee, one against the seller’s OAuth-connected merchant account for the seller share.
You receive funds directly in your PSP account — no manual transfers or reconciliation needed.

​
Fees and Settlement

ItemCost
Nevermined fee2% of the transaction amount
PSP processing feeStripe / Braintree fixed fee + % per transaction (varies by currency/region; see PSP pricing)
Supported currenciesUSD, EUR
SettlementStripe PaymentIntents (Stripe + Visa) or Braintree transaction.sale (Braintree) to seller’s connected account
Fiat payments carry higher fees than stablecoin payments (2% + Stripe fees vs. 1% flat). For high-volume or high-value use cases, consider stablecoin payments to reduce costs.

​
Supported Plan Types

Credits-Based

Prepaid credits purchased via Stripe Checkout. Credits are minted once payment confirms.

Time-Based

Subscription access for a set duration. Stripe handles recurring billing automatically.

Pay-As-You-Go

Per-request charging via card delegation. No upfront purchase needed.

Recurring

Automatic rebilling at the end of each period. Stripe manages the billing cycle.

​
Next Steps

Nevermined Pay

Enroll Visa, Stripe, or Braintree cards and create spending delegations for agent payments

Stablecoin Payments

Accept crypto payments with the lowest fees and on-chain transparency

Payment Models

Configure credits, time-based, dynamic, and hybrid plans

Manage Plans

Create and manage payment plans in the Nevermined App