pay-json
pay.json — machine-readable pricing standard for AI agents (like robots.txt for payments)
In the AI payments ecosystem
pay-json is an early-stage Python project in the AI payments / x402 ecosystem, focused on ai-agents, machine-readable, micropayments, open-standard. It currently has 0 GitHub stars and 0 forks, and sits alongside related tools like ClawRouter, x402-client, APIbase, marketplace-service-template, dna-x402, piprail.
pay.json
An open standard for machine-readable pricing — like robots.txt but for payments.
pay.json tells AI agents what content costs and how to pay for it. Publishers place a pay.json file at their domain root (/.well-known/pay.json) describing pricing rules and accepted payment methods.
Quick Example
{
"version": "1.2",
"protocol": "x402",
"network": "base",
"asset": "USDC",
"receiver": "0x1234567890abcdef1234567890abcdef12345678",
"seller_wallet": "0x1234567890abcdef1234567890abcdef12345678",
"facilitators": [
{ "name": "payai", "url": "https://facilitator.payai.network", "priority": 1, "spec_version": "v2" },
{ "name": "xpay", "url": "https://facilitator.xpay.sh", "priority": 2, "spec_version": "v2" }
],
"rules": [
{ "path": "/blog/*", "price_usd": "0.003" },
{ "path": "/premium/*", "price_usd": "0.01" }
]
}
facilitators[] lets the publisher list which x402 settlement providers they
accept. Agents try them in order and fall back through the list. No single
intermediary sits in the money path.
Specification
The full spec lives in spec/.
Tools
Validation and generation tools in tools/.
License
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