x402 overview
x402 is how intenthybrid AI lets machines pay for reads. Every read can be exposed as an HTTP endpoint that an agent or tool pays for per call, with a small amount of USDC settled onchain, and no keys, accounts, or monthly invoice. This page explains the idea. The x402 quickstart shows it in practice.
The idea in one line
A read is an endpoint a machine can pay for, in a single HTTP round trip, for a few cents.
Why this exists
Traditional APIs gate access behind accounts, API keys, and billing. That works for humans setting up an integration once, but it is friction for an agent that wants one read, right now, and may never call again. x402 replaces the account-and-key model with pay-per-request settlement, so an autonomous agent can pay for exactly what it uses without anyone provisioning credentials.
This is the layer that makes intenthybrid AI agent-native. A machine can buy a risk read the same way it would make any other HTTP request, plus a payment step.
The flow
The pattern follows the HTTP 402 status, "Payment Required", which the standard repurposes for programmatic micropayments. An illustrative read request looks like this:
- The client requests a read, for example
GET /v1/read?sym=BTCUSDT. - The server responds with 402 and a quote, for example a fraction of a cent up to a few cents of USDC.
- The client signs a payment authorization locally. No key is handed to the server.
- A facilitator settles the payment onchain.
- The server returns 200 with the read delivered.
In the reference walkthrough this whole exchange completes in roughly 600 milliseconds, with no key exchanged and no account created. The exact endpoint path, the price, and the settlement details are configuration, the values above are examples.
What you get from it
- Per-request pricing, down to a fraction of a cent, so an agent pays only for the reads it takes.
- No keys or accounts, so there is nothing to provision, rotate, or leak.
- Agent-native access, so software can pay without a human in the loop.
Status
The x402 paid read API is in active development. Treat the endpoint shapes and prices in this section as illustrative until the API is published. See the Roadmap.