PayPal
Connect PayPal to take payments and refunds, send invoices and payment links, manage subscriptions, answer disputes, and track sales and payouts.
You end up pasting the Client ID and Secret of a REST app from the PayPal developer dashboard. Every PayPal business account already has a Default Application you can use; PopMCP works out on its own whether the app is a live or a sandbox one.
- Setup time
- 5 min
- Auth
- API credentials
- API base URL
- https://api-m.paypal.com
- Rate limits
- PayPal publishes no fixed rate limit and throttles traffic that looks abusive with 429 RATE_LIMIT_REACHED; the Payouts API allows 400 POST requests a minute. Access tokens last about 9 hours and PopMCP reuses them.
Before you begin
- A PayPal business account (going live and testing outside the US both need one); a free developer account is enough for sandbox testing in the US
- Access to developer.paypal.com with that PayPal login
- Transaction search, Invoicing, Subscriptions and Customer disputes are app features you tick yourself; nothing to apply for
- Payouts only: PayPal support has to switch Payouts on for a live account before payouts can be sent
Get your credentials
Open Apps & Credentials
Log in at developer.paypal.com with your PayPal business account and open Apps & Credentials. Use the Live toggle for your real account, or Sandbox to try PopMCP with test money first.
Apps & Credentials
REST API apps and the credentials they call PayPal with.
| App name | Client ID | Created |
|---|---|---|
| Default ApplicationMerchant | AYsq****bE4k | Jan 12, 2026 |
Every business account starts with a Default Application. Use it, or create an app just for PopMCP.
Create an app for PopMCP (optional)
Click Create App, name it PopMCP, keep Merchant as the Type and click Create App. On the Sandbox toggle, also pick the sandbox business account the app should act for. The app's details page opens.
Apps & Credentials
Tick the features the AI should use
On the app's page, scroll to Features and tick what you want PopMCP to reach: Transaction search (sales totals, transaction history and balances), Invoicing, Subscriptions, Customer disputes, and Payouts if you send money out. Click Save Changes.
PopMCP
Merchant app
Choose what this app can do.
A feature ticked after you connect can take a few hours to start working.
Copy the Client ID and Secret
On the same page, copy the Client ID, then show the Secret under Secret key 1 and copy it too. Both must come from the same app.
PopMCP
Merchant app
- Client ID
- AYsq****bE4k
- Secret key 1
- EGnH****kZRb
The Secret is only used on PopMCP's servers, to get PayPal access tokens. It is stored encrypted.
Connect in PopMCP
Paste the Client ID and the Secret into PopMCP's PayPal form and click Connect PayPal. PopMCP checks the pair with PayPal, finds out whether it is a live or a sandbox app, and shows the account it belongs to.
Connect in PopMCP
Open your workspace, choose PayPal in the marketplace, and fill in the connect dialog:
| Field | What to enter |
|---|---|
| Client IDtext | At developer.paypal.com, log in with your PayPal business account, open Apps & Credentials (Live or Sandbox), choose your app and copy the Client ID. |
| Secretsecret | On the same app's page, under Secret key 1. Stored encrypted and used only on our servers to get PayPal access tokens.Encrypted with AES-256-GCM on save and never shown again. |
PopMCP verifies the credential against PayPal immediately. On success the connection flips to Verified and its MCP tools are provisioned.
Verify it worked
PopMCP shows the PayPal connector as Connected with the account name (marked sandbox for a sandbox app) and lists any of the features above that are still turned off in the app.
Troubleshooting
PayPal did not accept this Client ID and Secret
Why: The two values come from different apps, the Secret was copied with a space or cut short, or the app was deleted.
Fix: Open the app in Apps & Credentials, copy the Client ID and Secret key 1 from that one page again, and paste only the values.
A tool says a feature is turned off
Why: PayPal refuses calls for an app feature that is not ticked, such as Transaction search for sales totals and balances.
Fix: Tick the feature under the app's Features and click Save Changes. A feature ticked after connecting can take a few hours to start working.
Nothing with that id was found
Why: Live and sandbox are separate systems: an order, invoice or dispute id from one is not found on the other.
Fix: Check the connection is the system the id came from (the connector card says sandbox for a sandbox app), and connect the other app if needed.
Transactions from today are missing
Why: PayPal's transaction search can take up to three hours to show a new transaction, and covers at most 31 days per call.
Fix: Check again later; for longer ranges ask for a sales summary, which splits the range for you.
Payouts are refused on a live account
Why: Payouts is not switched on for the account, or the app's Payouts feature is not ticked.
Fix: Ask PayPal support to enable Payouts for your business account, then tick Payouts in the app's Features.
Reference
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