Monetizing HTTP resources with x402: how to charge for pages, APIs and agent tools
Learn how to design an x402-compatible Monetization Gateway with rules, verification, protected origins, variable pricing and reconciliation.
Author
Gustavo Sanchez Palencia
Leading AZPay’s relaunch
Gustavo Sanchez Palencia, also referred to as Gustavo Palencia, leads AZPay’s relaunch with the support of AI agents. That is the relationship described on the About page.
On his own site he presents himself as the founder of AZPay, AIDAX and Yebo, companies he says were sold to Layer2. He describes AZPay as a payment product with a transparent multi-processor checkout, cost routing, payment rules and sales recovery. That path started at AZClick, the digital agency and incubator he dates to 2012.
Since October 2025 he has been CTO at Rentcars. He is the creator of Trydak and builds MCP tools, including one for Google Search Console and one for WordPress. He also sits on the board of Hemp Vegan as country manager in Brazil and on the executive board of Linha Canábica. Earlier, his site lists him as VP of Technology at Remessa Online, CTO at ForSign, and a board member at Sthorm and 8D Hubify.
Articles
Pix for B2B invoices: due dates, payment allocation, and open balances
Use Pix for B2B receivables in Brazil: connect invoices, due-date charges and confirmed payments, and handle partial settlement without losing the open balance.
Local payment methods in Brazil: Pix, wallets and platforms
Understand Pix, Mercado Pago, PagBank/PagSeguro and PicPay, and distinguish payment methods, wallets and providers when planning for Brazil.
Mercado Pago in Brazil: checkout, Pix and integration decisions
Understand Mercado Pago in Brazil, how it differs from Pix, and what to evaluate about checkout, confirmation and payment operations.
PagBank/PagSeguro in Brazil: checkout, payment links and methods
Explore PagBank Checkout and Payment Links, Pix and boleto options, and the documentation, confirmation and operational checks that matter.
PicPay in Brazil: Wallet PicPay, Pix and business checkout
Distinguish Wallet PicPay, Pix and cards in E-commerce Checkout, with practical checks for confirmation, customer experience and operations.
What is Pix? How Brazil’s instant payment system works
Understand Pix in Brazil: paying and receiving, keys, QR codes, confirmation, fees, security, and requirements for international businesses.
Accepting Pix as an international business: what to verify first
Check eligibility, the contracting entity, collection in Brazil and international settlement before integrating Pix for your business.
Pix refunds: commercial returns, MED and card chargebacks
Understand commercial Pix refunds, MED and card chargebacks, and organize support to avoid refunding the same payment twice.
Pix checkout on the same phone: copy, return and confirmation
Design mobile Pix checkout with Copy and Paste, bank-app return, server confirmation, expiration handling and order recovery.
Boleto with Pix: how to prevent duplicate payments in hybrid billing
Learn how to link boleto and Pix to one obligation, confirm payments, and handle cancellation, duplicate receipts, and refunds with traceability.
Pix Automático for subscriptions: authorization, billing, and cancellation in practice
Understand authorization, cycles, failures, and cancellation in Pix Automático, and how to separate the commercial subscription from each payment’s states.
Cost per approved payment: how to compare PSPs beyond the advertised rate
Compare PSPs using auditable formulas, costs per attempt, approval, and paid order, plus a fictional numerical example with sensitivity analysis.
PSP migration: how to plan the transition without interrupting recurring charges
Plan a PSP migration with a token inventory, group-based cutover, control of pending cycles, reconciliation, and rollback criteria.
Split payments in marketplaces: allocation, payouts, and reconciliation without confusion
Learn to separate split allocation, capture, settlement, and payouts, with an example covering fees, partial refunds, and reconciliation by recipient.
Inside Pix: payment requests, QR codes, confirmation, refunds, and webhooks
Understand Pix payment requests, QR codes, txid, EndToEndId, confirmation, refunds, webhooks, and reconciliation for a robust commercial integration.
Payment fraud prevention: where risk, authentication, PSPs, and checkout meet
Understand how fraud prevention connects risk signals, 3DS, authorization, checkout, chargebacks, and experience to reduce losses without destroying conversion.
Payment timeouts: what to do when the PSP does not respond but the charge may have happened
Learn to handle timeouts, unknown states, retries, idempotency, failover, and reconciliation without creating duplicate charges.
Embedded checkout vs. hosted checkout: architecture, security, and experience
Compare embedded checkout, hosted pages, and hosted fields for UX control, PCI DSS, tokenization, multi-PSP, and implementation speed.
Chargebacks: disputes, evidence, prevention, and the post-sale lifecycle
Understand chargebacks, dispute reasons, evidence, representment, prevention, reconciliation, and how risk continues after capture.
Payment ledgers: why balances, transactions, and financial movements are different
Understand ledgers, accounts, entries, double-entry bookkeeping, available balances, fees, refunds, payouts, and reconciliation in financial infrastructure.
Idempotency in payment APIs: how to prevent duplicate charges during retries
Understand idempotency keys, deduplication, retries, concurrency, webhooks, and state machines to prevent duplicate financial effects.
Partial authorization, partial capture, and multiple captures: when the final amount changes
Understand partial authorization, partial capture, multiple captures, authorization adjustments, and how to model amounts that change throughout a payment.
Zero Auth in payments: how to validate a card without charging it
Understand how Zero Auth verifies a credential without a conventional charge and where it fits into tokenization, card-on-file, subscriptions, and payment architecture.
MCP, ACP, UCP, and AP2: what each protocol solves in agentic commerce
Compare MCP, ACP, UCP, and AP2 in agentic commerce: tools, checkout, capabilities, mandates, and the limits of payment authorization.
Fraud prevention before Black Friday: how to investigate blocked legitimate purchases
Learn how to investigate fraud false positives on Black Friday, identify improper blocks, and protect legitimate sales without increasing risk.
Payment reconciliation: how to verify that sales, captures, and settlement match
Learn how to reconcile orders, charges, captures, fees, refunds, and settlements to explain financial discrepancies with a traceable record.
Payments on Black Friday 2026: what to test before peak sales
Prepare payments for Black Friday with load, Pix, card, timeout, and webhook tests, plus recovery and reconciliation criteria.
Payment decline codes: soft declines, hard declines, and technical errors
Understand soft declines, hard declines, and technical failures, and classify them to guide retries, authentication, routing, and customer experience.
Payment observability: finding where and why a transaction failed
Logs, metrics, traces, and states for investigating failures, latency, and performance in multi-PSP payment infrastructure.
Gateway, PSP, acquirer, and sub-acquirer: who does what in payments
Understand the differences between gateways, PSPs, acquirers, and sub-acquirers and where each role fits into payment architecture.
Payment approval rates: measuring, diagnosing, and improving without shortcuts
Learn to measure approval rates, separate declines from technical errors, and diagnose opportunities to optimize payments.
Payment failover: building redundancy without duplicate charges
Learn how to design payment failover, retries, and fallback with idempotency, state management, and protection against duplicate charges.
Smart routing in payments: choosing the best route for each transaction
Understand smart routing, rules, signals, fallback, and metrics for choosing payment routes with control and explainability.
Payment transaction states: authorization, capture, cancellation, reversal, and refunds
Understand a payment transaction’s lifecycle, the differences between authorization, capture, cancellation, and refunds, and why intermediate states matter.
Payment orchestration: what it is, how it works, and why use multiple PSPs
Understand payment orchestration, multiple PSPs, smart routing, failover, and the foundations of a resilient architecture.
AI agent payments: what changes when checkout is no longer a screen
Understand how agentic commerce connects agents, checkout, authorization, tokenization, payments, and operations without replacing the merchant’s infrastructure.
Recurring payments: designing subscriptions, billing cycles, and card-on-file
Understand subscriptions, tokenization, card-on-file, retries, dunning, and the states needed for reliable recurring payments.
Card tokenization: PAN, vaults, card-on-file, and network tokens explained
Understand card tokenization, vaults, card-on-file, network tokens, portability, and the impact of credentials on a multi-PSP architecture.
Payment webhooks: preventing duplicate events and inconsistent states
Learn to authenticate, deduplicate, and process payment webhooks with idempotency, retries, ordering, and observability.
3DS in payments: frictionless, challenge, data-only, and conversion impact
Understand 3DS, frictionless and challenge flows, Data-Only, fraud prevention, and how authentication influences conversion and approval.