open_tab

Open a metered payment tab with a service provider. The provider can charge per-unit (per API call, per token, per query, etc.) up to your spend limit.

SERVERRemit Md MCP Server SOURCEpay-skill/mcp

Critical RISK CLASS

Category Financial

Parameters 00 required

Recommended Approval-gatedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/pay-skill-mcp/open-tab.md

WHAT IT DOES

What open_tab does on Remit Md MCP Server

AI agents use open_tab to commit financial operations through Remit Md MCP Server, usually the final step of a payment, billing, or trading workflow. A call moves real money.

RISK

Why open_tab is rated Critical

This tool initiates a financial arrangement where a third-party provider can repeatedly charge the agent per unit of usage up to a defined spend limit. It commits financial obligations on behalf of the user, making it a Financial category tool.

From the tool's definition 'Open a metered payment tab with a service provider. The provider can charge per-unit (per API call, per token, per query, etc.) up to your spend limit.'

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs open_tab safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Remit Md MCP Server, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For open_tab, this is the rule to start with:

open_tab Approval-gated

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

View as policy code

policy.json

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

GATE THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Remit Md MCP Server, apply this rule, and every open_tab call is checked against it from then on.

FAQ

Questions about open_tab

What does the open_tab tool do? +

Open a metered payment tab with a service provider. The provider can charge per-unit (per API call, per token, per query, etc.) up to your spend limit. It is categorised as a Financial tool in the Remit Md MCP Server MCP Server, which means it involves financial transactions. Block by default and require explicit approval.

How do I enforce a policy on open_tab? +

Register the Remit Md MCP Server MCP server in PolicyLayer and add a rule for open_tab: 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 Remit Md MCP Server. Nothing to install.

What risk level is open_tab? +

open_tab 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 open_tab? +

Yes. Add a rate_limit block to the open_tab 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 open_tab completely? +

Set action: deny in the PolicyLayer policy for open_tab. 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 open_tab? +

open_tab is provided by the Remit Md MCP Server MCP server (pay-skill/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

More on Remit Md MCP Server, and thousands of servers like it.

This server

All 28 Remit Md MCP Server tools → Critical-risk tools on this server →

Across the catalogue

All critical-risk MCP tools → The MCP Attack Database →

Guides

Govern MCP payment tools →Human-in-the-loop →Tool call approval →