util_luhn_valid

Luhn check for digit strings (cards/IDs)

SERVERDelx MCP Server SOURCEdelx-mcp-server

Low RISK CLASS

Category Read

Parameters 11 required

Recommended Allowedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/io-github-davidmosiah-delx-mcp-server/util-luhn-valid.md

WHAT IT DOES

What util_luhn_valid does on Delx MCP Server

AI agents call util_luhn_valid to retrieve information from Delx MCP Server without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

Parameter	Type	Required	Description
`number`	string	Yes	Input field: number.

Parameters from the server's own tool schema.

RISK

Why util_luhn_valid is rated Low

Even though util_luhn_valid only reads data, uncontrolled read access leaks sensitive information and racks up API costs: an agent caught in a retry loop can make thousands of calls a minute without anyone noticing.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs util_luhn_valid safely

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

util_luhn_valid Allowed

util_luhn_valid is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "util_luhn_valid": {}
  }
}

ALLOW ONLY THIS TOOL → Instant setup, no code required.

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

FAQ

Questions about util_luhn_valid

What does the util_luhn_valid tool do? +

Luhn check for digit strings (cards/IDs). It is categorised as a Read tool in the Delx MCP Server MCP Server, which means it retrieves data without modifying state.

What parameters does util_luhn_valid accept? +

util_luhn_valid accepts 1 parameter: number. Required: number. The full parameter table on this page comes from the server's own tool schema.

How do I enforce a policy on util_luhn_valid? +

Register the Delx MCP Server MCP server in PolicyLayer and add a rule for util_luhn_valid: 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 Delx MCP Server. Nothing to install.

What risk level is util_luhn_valid? +

util_luhn_valid is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit util_luhn_valid? +

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

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

util_luhn_valid is provided by the Delx MCP Server MCP server (delx-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

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

This server

All 740 Delx MCP Server tools →

Across the catalogue

The MCP Attack Database →

Guides

Roll out MCP under one policy →Data exfiltration →MCP token cost →