Comparison
One ledger. Two doors in.
Humans keep Stripe Checkout and Studio Buy actions. Agents on MCP, CLI, and REST can settle the same credit packs and locked generation quotes with USDC over x402. Credits spend identically no matter which rail funded them.
- Humans
- Stripe
- Agents
- x402
- Ledger
- Shared
Choose the rail that matches the operator
Follow the sequence in order. Each step is a bounded operator action—not a promise that every deployment has x402 enabled.
- 01
Person in a browser
Use subscriptions and credit packs on /pricing. Card and local payment methods complete in Stripe Checkout; agents must not enter card details in chat.
- 02
Agent in a loop
Use x402 when a local wallet is configured and the API returns PAYMENT-REQUIRED. Settlement stays inside the HTTP request cycle—no redirect, no email receipt wait.
- 03
Same prices
Published pack sizes and locked generation quotes price both rails. x402 cannot raise a charge the router already locked.
- 04
Same safeguards
API-key auth runs first on both rails. x402 adds a client spend cap and idempotent grants on the settlement transaction hash.
- HumansStripe
Studio pricing, subscriptions, and Checkout URLs for browser completion.
- Agentsx402
HTTP 402 challenge, local signature, onchain USDC settlement, then credits.
- LedgerShared
Plan credits and top-ups fund one balance used by web, MCP, CLI, and API.
Runbook FAQ
Do humans need a crypto wallet?
No. People continue to use Stripe. x402 is the second rail for API-key agents that can hold a local wallet key.
Can both rails fund the same account?
Yes. Stripe and x402 grant credits into the same ledger at the same published prices.
Keep payment decisions explicit.
Humans stay on Stripe. Agents settle only with a local wallet and a spend cap. When the shape is unclear, start with the PAYMENT-REQUIRED diagnosis runbook.