sms_format_number

Validate a phone number and return its E.164 form, national format, and country code.

SERVERTwilio SMS MCP Server SOURCE0x-professor/twilio-mcp-server

Low RISK CLASS

Category Read

Parameters 00 required

Recommended Allowedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/0x-professor-twilio-mcp-server/sms-format-number.md

WHAT IT DOES

What sms_format_number does on Twilio SMS MCP Server

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

RISK

Why sms_format_number is rated Low

This is a pure data transformation and validation utility. It takes a phone number as input and returns formatted/validated versions without any side effects—no messages sent, no data modified or deleted, no external operations triggered. It functions as a read-only helper tool for preparing phone number data, similar to a parsing or validation function.

From the tool's definition Tool performs validation and formatting of phone numbers, returning parsed data (E.164 form, national format, country code) with no modification or transmission of data.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs sms_format_number safely

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

sms_format_number Allowed

sms_format_number 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": {
    "sms_format_number": {}
  }
}

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

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

FAQ

Questions about sms_format_number

What does the sms_format_number tool do? +

Validate a phone number and return its E.164 form, national format, and country code. It is categorised as a Read tool in the Twilio SMS MCP Server MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on sms_format_number? +

Register the Twilio SMS MCP Server MCP server in PolicyLayer and add a rule for sms_format_number: 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 Twilio SMS MCP Server. Nothing to install.

What risk level is sms_format_number? +

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

Can I rate-limit sms_format_number? +

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

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

sms_format_number is provided by the Twilio SMS MCP Server MCP server (0x-professor/twilio-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

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