ebay_register_client

THE RISK

Critical Risk

This tool registers a financial application under Open Banking / PSD2 frameworks, which directly establishes financial access rights and obligations. Registering a third-party financial app can grant it access to payment flows and financial data on eBay.

From the tool's definition Register a third party financial application with eBay (Open Banking / PSD2). Requires valid eIDAS certificate via MTLS.

Documented attack patterns abuse exactly the kind of access ebay_register_client gives an agent:

HOW TO CONTROL EBAY_REGISTER_CLIENT

PolicyLayer is an MCP gateway — it sits between your AI agents and Ebay, and nothing reaches the server without passing your rules. This is the rule we recommend for ebay_register_client:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "ebay_register_client": {
      "deny_if": [
        {
          "conditions": [],
          "on_deny": "Requires human approval."
        }
      ]
    }
  }
}

Any call to ebay_register_client is blocked until a human approves it. The rest of the server keeps working.

Create a free account and register Ebay — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

GATE THIS TOOL →

Free to start. No card required.

EXPLORE

More Ebay tools

Financial ebay_issue_refund Issue a full or partial refund for an eBay order. Use this to refund buyers for orders, in Financial ebay_withdraw_offer Withdraw a published offer Financial ebay_withdraw_offer_by_inventory_item_group Withdraw an offer for an inventory item group (variation listing).\n\nRequired OAuth Scope Financial ebay_accept_payment_dispute Accept a payment dispute and allow eBay to refund the buyer. Use this when you agree with Financial ebay_opt_in_to_payments_program Opt-in to a payments program Destructive ebay_bulk_cancel_packages Cancel multiple packages in one request Destructive ebay_bulk_delete_ad_group_negative_keywords Delete multiple ad group-level negative keywords. Destructive ebay_bulk_delete_ads_by_inventory_reference Delete multiple ads by inventory reference. CPS campaigns only.

All 332 Ebay tools →

Financial tools on other servers

Atv build_deposit_tx Bitcoin MCP Server pay_invoice AbraFlexi bank_transaction_create Hilanet MCP decrease_coworker_salary

Go deeper

Critical-risk tools in Ebay → Every critical-risk tool this server exposes, in one view.
All critical-risk MCP tools → Every critical-risk tool across the catalogue, and the policy pattern that contains them.
The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
How to Add Spending Controls to Any MCP Agent →
Rate Limiting MCP Tool Calls: A Practical Guide →

FAQ

What does the ebay_register_client tool do? +

Register a third party financial application with eBay (Open Banking / PSD2). Requires valid eIDAS certificate via MTLS. It is categorised as a Financial tool in the Ebay MCP Server, which means it involves financial transactions. Block by default and require explicit approval.

How do I enforce a policy on ebay_register_client? +

Register the Ebay MCP server in PolicyLayer and add a rule for ebay_register_client: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Ebay. Nothing to install.

What risk level is ebay_register_client? +

ebay_register_client is a Financial tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.

Can I rate-limit ebay_register_client? +

Yes. Add a rate_limit block to the ebay_register_client rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block ebay_register_client completely? +

Set action: deny in the PolicyLayer policy for ebay_register_client. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides ebay_register_client? +

ebay_register_client is provided by the Ebay MCP server (yosefhayim/ebay-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Ebay tool call.

Deterministic rules across all 332 Ebay tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.

GOVERN EBAY →

Free to start. No card required.

332 Ebay tools catalogued and risk-classified — across an index of 42,500+ MCP servers.

// WHAT EBAY_REGISTER_CLIENT ON EBAY DOES

// THE RISK

// HOW TO CONTROL EBAY_REGISTER_CLIENT

// EXPLORE