payments.txt

The open standard for machine-readable payment profiles.
Like robots.txt and llms.txt — but for getting paid by AI agents.

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What is payments.txt?

payments.txt is a plain-text file served at /{handle}/payments.txt that tells AI agents, billing systems, and autonomous software how to pay you — without any human in the loop.

It describes:

• Your crypto wallets (EVM, Solana)
• Your bank details (SEPA, ACH)
• Your payment terms (due days, late fees, preferred currency)
• Your X402 endpoint for autonomous HTTP-level payments
• A human fallback URL for anything that needs a checkout page

Inspired by robots.txt (1994) and llms.txt (2024). payments.txt is the payment layer for the agentic web.

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The problem it solves

AI agents increasingly handle scheduling, procurement, invoicing, and payments on behalf of humans. Today, every payment requires either:

1. A human to click through a checkout page, or
2. A custom API integration per vendor

Neither scales. payments.txt gives agents a standard discovery mechanism — one file, consistent format, no integration work.

Agent reads:  https://vendor.com/payments.txt
Agent knows:  EVM wallet, preferred USDC, payment terms, X402 endpoint
Agent pays:   Autonomously, no human needed

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File format

payments.txt uses an INI-style format. All sections are optional — include only what applies to you.

# PAYMENTS.TXT
# Human-readable payment profile for autonomous agents

[meta]
version                  = "1.0"
status                   = "active"
x402_discovery_url       = "https://api.example.com/v1/x402/handle"
x402_payment_endpoint    = "https://api.example.com/v1/x402/handle/pay"

[payment_terms]
due_days                 = 14
late_fee_percentage      = 2.0
preferred_fiat           = "EUR"
preferred_crypto         = "USDC"

[crypto_rails]
supported_standards      = ["EVM", "Solana"]
primary_stablecoin       = "USDC"
evm_address              = "0xYourEVMAddress"
solana_address           = "YourSolanaAddress"

[fiat_rails]
sepa_iban                = "NL15BUNQ2106989466"
sepa_bic                 = "BUNQNL2AXXX"
ach_routing              = "021000021"
ach_account              = "000123456789"

[hosted_checkout]
human_fallback_url       = "https://payrequest.me/handle"

Full specification: spec/payments-txt-v1.md

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X402 integration

payments.txt pairs with the X402 protocol for autonomous HTTP-level payments. X402 uses the 402 Payment Required HTTP status code to negotiate and settle USDC payments without a human checkout flow.

GET  /{handle}/payments.txt            → discover wallets + X402 endpoint
POST /api/v1/x402/{handle}/pay         → 402 with payment requirements
POST /api/v1/x402/{handle}/pay         → X-Payment header → 200 + receipt

See spec/x402-integration.md for the full protocol.

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Quick start

Auto-generated (PayRequest)

Every PayRequest page auto-publishes a payments.txt manifest. Fill in your wallet in settings — done.

Live example: payrequest.me/geertjan/payments.txt

Static file

Drop a payments.txt in your site root served as text/plain; charset=UTF-8.

HTML discovery tag

<link rel="payments" type="text/plain" href="https://yoursite.com/payments.txt">

Laravel

Route::get('/{handle}/payments.txt', [PaymentManifestController::class, 'show']);

Full guide: implementations/laravel.md

Node.js

app.get('/:handle/payments.txt', (req, res) => {
  res.type('text/plain').send(`[meta]\nversion = "1.0"\nstatus = "active"\n\n[crypto_rails]\nevm_address = "${process.env.EVM_WALLET}"\n`);
});

Full guide: implementations/nodejs.md

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Specification

Document	Description
spec/payments-txt-v1.md	Full file format spec — all fields, types, parsing rules
spec/x402-integration.md	X402 HTTP 402 autonomous payment flow
spec/discovery.md	How agents discover payments.txt

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Examples

File	Description
examples/minimal.txt	Crypto-only, minimal setup
examples/freelancer.txt	Freelancer with SEPA + USDC
examples/business.txt	Full business profile (USDC + SEPA + ACH)
examples/crypto-native.txt	All chains, no fiat

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Implementations

Language	Status	Link
PHP	✅ Reference	implementations/php.md
Node.js / Express	✅ Example	implementations/nodejs.md
Python / FastAPI	📋 Planned	—
WordPress plugin	📋 Planned	—

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How payments.txt compares

	robots.txt	llms.txt	payments.txt
Purpose	Crawl control	LLM context	Payment discovery
Audience	Web crawlers	LLM agents	AI agents / billing systems
Format	Rules-based	Markdown	INI-style
Year proposed	1994	2024	2025
Agent action	Passive (skip)	Passive (read)	Active (pay)
Requires server logic	No	No	Optional (X402)

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Contributing

This is an open standard. Contributions welcome:

• New implementations — Python, Go, Ruby, WordPress, etc.
• Spec improvements — edge cases, new rails (Lightning, Farcaster frames)
• Tooling — validators, parsers, agent SDKs

Open an issue or PR. No CLA required.

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License

MIT — free to use, implement, and extend.

Built by PayRequest — the open payment layer for the agentic web.