HTTP 402 for AI Agents
HTTP 402 is becoming the handshake between autonomous agents and paid APIs. The protocol can request payment; SatGate decides whether the agent should be allowed to pay, access, and continue.
What HTTP 402 means in an agent world
For years, HTTP 402 Payment Required was mostly dormant. AI agents make it useful: a paid API can respond with a machine-readable challenge instead of forcing a human through checkout.
That challenge may point to different rails: card-based credentials, shared payment tokens, L402 Lightning invoices, or future protocols. But the payment challenge is not the governance layer.
SatGate sits before upstream access and applies policy: identify the agent, estimate cost, enforce budgets, decide whether the rail is allowed, record the challenge, and unlock only scoped access after proof.
A 402-aware control plane asks
HTTP 402 flow types
Treat 402 as a protocol surface, not a single payment system. SatGate Charge is L402 Lightning; other payment-token flows are separate rails that still need governance.
Where SatGate fits in a 402 exchange
Agent requests
An agent calls a paid API, model endpoint, MCP tool, or dataset.
SatGate evaluates
Policy checks identity, scope, budget, route, tenant, and allowed payment rail.
402 is handled
SatGate can issue, observe, or audit a payment challenge depending on the route.
Access is governed
Only approved, scoped, metered, auditable access proceeds upstream.
L402 is SatGate Charge
SatGate Charge uses L402 Lightning: an API returns a 402 challenge, the agent pays a Lightning invoice, and payment proof unlocks scoped access. This is SatGate's robot-customer monetization rail.
Other 402 rails still need policy
Stripe-style shared payment tokens, card credentials, and future payment protocols can help agents pay. They do not replace request-path controls for budget, scope, revocation, metering, or audit.
FAQ
HTTP 402 for AI agents questions
What is HTTP 402 for AI agents?
HTTP 402 lets an API tell an AI agent that payment is required before access. The response can include a machine-readable challenge describing how to pay.
Is HTTP 402 the same as L402?
No. HTTP 402 is the status code. L402 is a Lightning-based payment and access pattern that uses HTTP 402. SatGate Charge uses L402 Lightning.
How are Stripe shared payment tokens different from L402?
Stripe-style shared payment tokens are a payment-credential method for supported 402 flows. L402 uses Lightning payment proof to unlock scoped API access. They are separate rails.
Why do 402 payment challenges need policy?
A payment challenge tells the agent how to pay, but it does not decide whether the agent should be allowed to spend, which budget applies, whether the route is in scope, or how the event should be audited.
Related guides
Stripe Link for Agents vs SatGate
Compare wallet credentials with request-path economic governance.
Agent payment controls
Policy, budgets, approval, audit, and payment rails for AI agents.
L402 agent payments
Use SatGate Charge to monetize APIs with Lightning-native robot-customer payments.
Robot customer payments
Turn autonomous agents into paying API customers.
Economic firewall
Control agent access and spend before upstream API calls execute.
L402 API pricing calculator
Estimate request-native pricing for agent/API monetization.
Make 402 programmable, governed, and auditable
SatGate gives API teams the economic firewall for agent-native payments: Observe every 402 and paid request, Control who may spend, and Charge with L402 Lightning when APIs become robot-customer products.