Google Merchant Center
Connect Google Merchant Center to manage product feeds, listings, local inventory, promotions, and performance reports.
You end up pasting an OAuth Client ID and Client Secret from a Google Cloud project that has the Merchant API enabled and has been registered as a developer against your Merchant Center account.
- Setup time
- 12 min
- Auth
- OAuth authorization
- API base URL
- https://merchantapi.googleapis.com
Before you begin
- A Google Merchant Center account with products or a feed
- Admin access level in Merchant Center. Developer registration requires it
- A Google Cloud project where you are Owner or Editor
- The Google Account you sign in with must also be a user on the Merchant Center account
Get your credentials
Enable the Merchant API on a dedicated Cloud project
Pick or create a project of your own, open APIs & Services -> Library, search for Merchant API, and click Enable. Enable merchantapi.googleapis.com, not the legacy Content API for Shopping.
Merchant API
Programmatic access to Merchant Center products, inventory and reporting.
| Related API | Status |
|---|---|
| Merchant APImerchantapi.googleapis.com | Not enabled |
| Content API for Shoppingshoppingcontent.googleapis.com | Legacy |
Same thing from the CLI: gcloud services enable merchantapi.googleapis.com
Register the Cloud project as a developer on your Merchant Center account
Sign in with an Admin-level Merchant Center account and call accounts.developerRegistration.registerGcp for that account, passing the project you just enabled. Wait about five minutes before your first API call.
Fill in the branding and publish the app
Under Google Auth Platform -> Branding set the app name, logo, support email and your homepage, privacy policy and terms links. Then open Audience and click Publish app if Publishing status reads Testing.
Audience
The user groups that can authorize your app to access their account data.
- App name
- PopMCP
- User support email
- support@popmcp.app
- Application home page
- https://popmcp.app
- Privacy policy link
- https://popmcp.app/privacy
Create a Web application OAuth client
Go to Google Auth Platform -> Clients, click Create client, choose Application type Web application, and name it PopMCP. Paste the exact callback URL from the PopMCP connect form under Authorized redirect URIs.
Create OAuth client ID
A client ID identifies your app to Google's OAuth 2.0 endpoint.
Copy the Client ID and Client Secret straight away
Copy both values out of the OAuth client created dialog into PopMCP's OAuth Client ID and OAuth Client Secret fields. If the dialog is gone, open the client and click Add secret.
Clients
| Name | Type | Client ID | Status |
|---|---|---|---|
| PopMCP1 secret | Web application | 4829****googleusercontent.com | Active |
After this dialog the console keeps only the last four characters of the secret.
Connect in PopMCP
Open your workspace, choose Google Merchant Center in the marketplace, and fill in the connect dialog:
| Field | What to enter |
|---|---|
| OAuth Client IDtext | From your Google Cloud project → APIs & Services → Credentials → OAuth client. Enable the Merchant API on the same project. |
| OAuth Client Secretsecret | Stored encrypted; used server-side only and never shown again.Encrypted with AES-256-GCM on save and never shown again. |
https://app.popmcp.com/api/providers/google/callbackPopMCP verifies the credential against Google Merchant Center immediately. On success the connection flips to Verified and its MCP tools are provisioned.
Permissions PopMCP requests
These are the scopes sent to Google Merchant Center at authorization time.
| Scope | Why PopMCP asks for it |
|---|---|
| https://www.googleapis.com/auth/content | The single Merchant API scope. It covers product feeds and listings, data sources, local and regional inventory, promotions, return policies, account settings and performance reports. |
Verify it worked
PopMCP opens Google's consent screen. Approve it and the connector flips to Connected with your Merchant Center account id shown. Ask the assistant to list a handful of products. Real titles coming back means the API is enabled, the scope is granted, and developer registration went through.
Troubleshooting
401 "GCP project with id ... is not registered with the merchant account"
Why: Developer registration was never run for this Cloud project. There is no Merchant Center UI for it, the registerGcp API call is the only way.
Fix: Run accounts.developerRegistration.registerGcp with an Admin Merchant Center login, then retry after about 5 minutes.
Authentication errors when using an API key
Why: Merchant API does not support API keys at all.
Fix: Use the OAuth client ID and secret. That is what PopMCP's two fields are for.
Consent succeeds but no products are visible
Why: The Google Account that signed in is not a user on the Merchant Center account, or is on a different sub-account.
Fix: Add that email on the Merchant Center Access and services page with at least Standard access, Admin for registration, then reconnect.
Connection stops working after about a week
Why: The OAuth app is still in Testing status, so the refresh token expires in 7 days.
Fix: Google Auth Platform -> Audience -> Publish app, then reconnect in PopMCP.
403 SERVICE_DISABLED for merchantapi.googleapis.com
Why: The Merchant API is enabled on a different project than the one the OAuth client belongs to.
Fix: Confirm the project picker matches, then enable Merchant API in APIs & Services -> Library on that project.