Articles on: XOBIN MCP

How to connect Xobin MCP to Gemini Enterprise?

Unlike Claude and ChatGPT, Gemini Enterprise does not auto-register an OAuth client. An administrator must register Gemini as an OAuth app on Xobin, then create a Custom MCP Server data store.

Contact your IT team to do the setup.

Note: **Gemini only supports Streamable HTTP (the Xobin URL ending in /mcp). Legacy SSE is not supported. Before proceeding, make sure you have reviewed the prerequisites and connection values in** Connecting Xobin to AI Assistants via MCP.

Step 1: Register Gemini as an OAuth Client on Xobin

Request a pre-registered Gemini client from Xobin, or register one directly against the MCP authorization server.
Gemini requires the following redirect URI:

https://vertexaisearch.cloud.google.com/oauth-redirect

Example registration request:

curl -sS -X POST "https://{MCP_HOST}/register" \
  -H "Content-Type: application/json" \
  -d '{
    "client_name": "Gemini Enterprise",
    "redirect_uris": [
      "https://vertexaisearch.cloud.google.com/oauth-redirect"
    ],
    "grant_types": ["authorization_code", "refresh_token"],
    "response_types": ["code"],
    "token_endpoint_auth_method": "none",
    "scope": "mcp:read mcp:write"
  }'

Save the returned client_id (and client_secret, if provided) in a secure secrets store — never in chat logs.

Warning: If registration fails or Gemini cannot exchange tokens, contact Xobin to provision the client. Redirect URIs are strictly enforced — Gemini will not connect without the exact URI above.

Step 2: Google Cloud Gemini Enterprise
Your Google Cloud project must allow Custom MCP data stores and egress to {MCP_HOST}. The user creating the data store needs the Discovery Engine Editor role (roles/discoveryengine.editor).

In the Google Cloud console, open Gemini Enterprise.
Go to Data Stores → Create Data Store.
Search for Custom MCP Server and click Add MCP Server.
Select OAuth 2.0 and enter the following:

Field	Value
MCP Server URL	https://{MCP_HOST}/mcp
Authorization URL	https://{MCP_HOST}/authorize
Token URL	https://{MCP_HOST}/token
Authorization URL Parameters	`&resource=https://{MCP_HOST}/mcp`
Client ID	From Step 1
Client Secret	From Step 1, or leave blank if the client is public
Enable PKCE Support	On
Scopes	`mcp:read` `mcp:write`

Note: Enter only the authorization base URL — Gemini automatically appends client_id, redirect_uri, and scope. The resource parameter tells Xobin which MCP resource to issue tokens for.

Click Verify Auth, sign in to Xobin, and approve access.
Choose a location, name the data store Xobin, and click Create.
Wait until the data store status shows Active.
Open Actions, reload custom actions, and enable the required Xobin tools (up to 100).
Connect the data store to your Gemini Enterprise app. In the chat UI, authorize the connector if it still shows Authorize, then enable it.

Step 3: Gemini Enterprise – Business Edition

Sign in at business.gemini.google.
Go to Settings & Help.
Select your team → Manage Team → Connected Apps.
Click Add MCP Server.
Enter the name Xobin, a short description of the hiring workflow, and the MCP Server URL https://mcp.xobin.com/mcp.
Fill in the same Authorization URL, Token URL, Client ID, Client Secret, PKCE, scopes, and &resource=https://{MCP_HOST}/mcp parameter as above.
Click Add, then enable the connection so your team can access it.
In chat, open Connectors, authorize Xobin, and keep it toggled on.

Confirming the Connection:

Test the connection with: "Using Xobin, what job tracks are open, and how many candidates are in each?"
Then test a write action you can safely review: "Draft (do not send) an assessment invitation for a candidate I name."

Troubleshooting:

Gemini "Verify Auth" fails.

Check the MCP URL (/mcp), Authorization URL (/authorize with no query string), Token URL (/token), PKCE settings, scopes (mcp:read mcp:write), and the resource parameter. Ensure the MCP host is allowed as an egress FQDN in your Google Cloud organization policy.

OAuth redirect error ("redirect_uri is not registered").

The registered redirect URI must exactly match https://vertexaisearch.cloud.google.com/oauth-redirect.

Updated on: 08/14/2026

Was this article helpful?

Thank you!