/paypal-best-practices

name: paypal-best-practices
description: >-
  PayPal integration guidance, code examples, and best practices.
  Use for checkout, card fields, BNPL, Pay Later, Venmo, subscriptions,
  invoicing, disputes, payouts, webhooks, APMs, JS SDK v5, JS SDK v6,
  createInstance, payment sessions, web components, Fastlane, payment links,
  donations, 3D Secure, vaulting, iDEAL, bank redirects, agentic commerce,
  or any PayPal architecture decision or code generation question.
when_to_use: >-
  "how do I integrate PayPal", "PayPal checkout example", "PayPal best
  practices", "PayPal subscriptions guide", "PayPal webhook setup",
  "PayPal error handling", "PayPal SDK code", "add Pay Later", "add Venmo",
  "PayPal card fields", "PayPal disputes", "PayPal invoices",
  "PayPal docs link", or any PayPal code generation request.
allowed-tools: Read, WebFetch, WebSearch
metadata:
  version: "1.1.0"
  category: payments-integration
  tags: checkout bnpl venmo subscriptions disputes apm fastlane webhooks

PayPal Best Practices

Before answering, read the relevant reference file from the table below. The reference files contain current documentation URLs, country availability, and verified code examples.

Integration Routing

| Developer intent | Reference file | |-----------------|----------------| | Accept payments, add PayPal button, checkout flow, Orders API, payment link, payment links, pay link, React PayPal, @paypal/react-paypal-js, authorize vs capture, deferred capture, donate button, donations | [references/checkout.md](references/checkout.md) (v5) or [references/js-sdk-v6.md](references/js-sdk-v6.md) (v6) | | Advanced Card Fields, Apple Pay, Google Pay, APMs, Expanded Checkout, bank redirect, iDEAL, Bancontact, BLIK, Przelewy24, Pay upon Invoice, Ratepay, domain association, regional payment methods | [references/expanded-checkout.md](references/expanded-checkout.md) (v5) or [references/js-sdk-v6.md](references/js-sdk-v6.md) (v6) | | Add Venmo, Venmo button, Venmo eligibility, isFundingEligible, eligibility check, Venmo app | [references/venmo.md](references/venmo.md) (v5) or [references/js-sdk-v6.md](references/js-sdk-v6.md) (v6) | | Pay Later, installments, BNPL messaging, Pay in 4, financing, BNPL banner, Pay Later banner, Pay Later eligibility | [references/bnpl.md](references/bnpl.md) (v5) or [references/js-sdk-v6.md](references/js-sdk-v6.md) (v6) | | Recurring billing, subscriptions, plan management, free trial, trial period, upgrade plan, downgrade plan, plan revision | [references/subscriptions.md](references/subscriptions.md) (v5) or [references/js-sdk-v6.md](references/js-sdk-v6.md) (v6) | | Disputes, chargebacks, refunds, evidence, provide evidence, dispute lifecycle, dispute stage, INQUIRY, CLAIM | [references/disputes-refunds.md](references/disputes-refunds.md) | | Send money, batch payouts, seller payments, Venmo payout, 1099, tax reporting, prepaid cards | [references/payouts.md](references/payouts.md) | | Invoices, billing, send invoice, invoice reminder, partial payment, line items | [references/invoicing.md](references/invoicing.md) | | OAuth, access tokens, credentials, idempotency, token caching, token refresh, idempotency key, PayPal-Request-Id | [references/authentication.md](references/authentication.md) | | Webhook verification, event handling, signature check, webhook simulator, test webhooks, event types, PAYMENT.CAPTURE | [references/webhooks.md](references/webhooks.md) | | Fastlane, accelerated guest checkout, auto-fill, prefill, single-use token, Braintree Fastlane, `braintree-web`, `BraintreeGateway`, `gateway.clientToken.generate`, `braintree.fastlane.create`, paymentMethodNonce | **Pick exactly one — three variants, do not mix.** Braintree gateway (`braintree-web`, `BraintreeGateway`, `paymentMethodNonce`): [references/fastlane-braintree.md](references/fastlane-braintree.md). PayPal-direct v5 (`paypal.Fastlane({})`, `data-sdk-client-token`): [references/fastlane.md](references/fastlane.md). PayPal-direct v6 (`sdkInstance.createFastlane()`): [references/js-sdk-v6.md](references/js-sdk-v6.md). If unclear which variant, ask before generating code. | | 3D Secure, liability shift, SCA, PSD2, Strong Customer Authentication, enrollment status, authentication status | [references/3d-secure.md](references/3d-secure.md) | | AI shopping agents, Store Sync, Agent Ready, agentic commerce, ChatGPT, product discovery, delegated payment token | [references/agentic-commerce.md](references/agentic-commerce.md) | | MCP server tools, tool inventory, product catalog, merchant insights, reporting | [references/mcp-tools.md](references/mcp-tools.md) | | JS SDK v6, v6 Web SDK, createInstance, payment sessions, web components, migrate from v5, card fields, vault, save card, save payment method, vaulting, CSP, Content Security Policy | [references/js-sdk-v6.md](references/js-sdk-v6.md) |

Code Generation Directive

Before writing any PayPal code, detect SDK version and read the correct reference:

1. **v5** — `sdk/js?client-id=` script tag, `paypal.Buttons()`, Hosted Fields → use `checkout.md` / `expanded-checkout.md` 2. **v6** — `web-sdk/v6/core` script tag, `createInstance`, `<paypal-button>` web components → use `js-sdk-v6.md` 3. **New project** (no existing SDK) — default to v6, use `js-sdk-v6.md` 4. **Unclear** — ask the user which version they are using

MCP Boundary

When the PayPal MCP server is connected, prefer MCP tools for live operations (creating orders, managing subscriptions, fetching disputes). Use this skill for architecture decisions, code generation, and integration guidance — not for executing API calls that MCP tools can handle directly.

Out of Scope

This skill does NOT cover:

• PayPal Commerce Platform (multi-party marketplaces) — see [Commerce Platform docs](https://developer.paypal.com/md/docs/multiparty/)
• PayPal Mobile SDKs (iOS/Android native) — see [Mobile SDK docs](https://developer.paypal.com/md/sdk/mobile/)
• Braintree direct integrat