How do I connect P0 to Gemini Enterprise as a custom MCP server?

In the Google Cloud console open Gemini Enterprise, Data stores, search for the Custom MCP Server card, click Add MCP server, choose No authentication and enter the MCP Server URL https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/mcp. An administrator with the Discovery Engine Editor role has to do it, and Google blocks custom MCP data stores by an organization policy until that constraint is overridden. The tools you can use through it are free: market search, market statistics and the list of P0's paid products.

Data as of 2026-10-25 · Source: Google Cloud: Set up your custom MCP server data store

The numbers

P0 MCP endpoint: https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/mcp
Transport: Streamable HTTP, JSON-RPC 2.0
Authentication: None required; an optional prepaid access key is accepted as Authorization: Bearer p0k_… (see the notes)
Free tools worth allowing: search_x402_services, x402_market_stats, list_paid_data_products

Steps in Gemini Enterprise

Step	What to do
1	Grant your administrator the Discovery Engine Editor role (roles/discoveryengine.editor) and override the organization policy constraint that blocks custom MCP data store creation.
2	If egress is restricted by organization policy, allow the host name of the P0 endpoint (the domain only, not the full URL); if project enforcement or VPC Service Controls apply, add custom_mcp to the allowed data sources.
3	In the Google Cloud console go to Gemini Enterprise, then Data stores, enter Custom MCP Server in the search field, select its card and click Add MCP server.
4	Authentication settings: No authentication. MCP Server URL: https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/mcp (HTTPS; Google says the URL often ends with /mcp).

What works through the connector, and what does not

Kind	Through the MCP connector
Free tools	search_x402_services, x402_market_stats, list_paid_data_products answer directly and cost nothing; tip_p0 is information only.
Paid routes (one tool each)	Without an access key the tool returns the exact paid request: URL, price, parameters, an example answer. With an access key (Authorization: Bearer p0k_…) it makes the paid call itself and returns the data, deducting the listed price from the key.
The paid data itself	The request answers HTTP 402 until it is paid. Pay with an x402 client or wallet, or by a direct transfer (below).

Copy-paste setup

Check the endpoint first (any shell)

curl -s -X POST https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'

Paying for the data

/keys/buy?usd=5: buy a prepaid access key with one x402 payment (usd=1, 5 or 20; $5 credits $5.25, $20 credits $22), then send it as Authorization: Bearer
/pay: free page: pay without an x402 client, by a direct transfer claimed with the transaction hash
/integrations: free page: runnable snippets that pay and call a route with an x402 client
/x402/test - $0.001 per call: the cheapest real paid call, to rehearse the payment with your client or wallet
/a2a: A2A endpoint with the x402 extension (GET returns the agent card)

Paid routes answer HTTP 402 with the payment requirements until paid over x402 or MPP (no account or key); see how to pay, pay without a client, OpenAPI. The figures on this page are also at ?format=json.

Limits and notes

Google's page states that the connector supports only the Streamable HTTP transport (SSE is not supported) and that the server needs a TLS certificate signed by a publicly trusted certificate authority; P0's endpoint is Streamable HTTP.
Google recommends no more than 100 enabled actions (tools) per custom MCP data store, and says an existing data store cannot be reused: you register a new one in your Gemini Enterprise app.
OAuth 2.0 is the other authentication option on Google's form; P0's endpoint does not use it.
Without an access key none of P0's MCP tools returns paid data. The connectors described here do not sign x402 payments (the documentation page used for this guide describes no payment support), so the paid call is made outside the connector, or with a prepaid access key (below).
To pay: use an x402-capable client or wallet (runnable JavaScript and Python snippets: https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/integrations), or send the price as a direct stablecoin or coin transfer and claim it with the transaction hash, GET <route>?tx=<hash> (details and addresses: https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/pay). The first call without payment shows the exact price.
Agents that speak A2A with the x402 extension can pay inside the A2A message flow at https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/a2a (the agent card lists the extension).
Access key (optional): an agent that cannot sign x402 buys a prepaid key once with x402 (USD 1, 5 or 20; the $5 key credits $5.25 of calls and the $20 key $22: https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/keys/buy?usd=5) and, where your platform lets you set an Authorization header or token for a remote MCP server, sends it as Authorization: Bearer p0k_…; the data tools then return the data and each call is deducted at its listed price. Balance is free at https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/keys/balance. Unused balance never expires and is not refunded. Where the platform has no such field, use the x402 route above.
The snippets follow the vendor documentation named below; P0 has not run them on a Gemini Enterprise account of its own.
Not legal, financial or security advice; P0 is not affiliated with or endorsed by any of the publishers named here.
Google Cloud: Set up your custom MCP server data store: Vendor documentation read on 2026-10-25; menu names, limits and plan availability change. P0 is not affiliated with or endorsed by Google.