voice_call_with_input · Telephony MCP Server MCP

WHAT IT DOES

What voice_call_with_input does on Telephony MCP Server

AI agents use voice_call_with_input to create or update resources in Telephony MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Telephony MCP Server environment.

WHY IT NEEDS A POLICY

Why voice_call_with_input needs a policy

An AI agent can call voice_call_with_input faster than any human can review — one bad instruction and it creates or modifies resources in Telephony MCP Server by the hundred, each call as confident as the last.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

voice_call_with_input Rate-limited

voice_call_with_input stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "voice_call_with_input": {
      "limits": [
        {
          "counter": "voice_call_with_input_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Telephony MCP Server, so you can run agents against it safely.

FAQ

Questions about voice_call_with_input

What does the voice_call_with_input tool do? +

Make a voice call to a given number and wait for speech input from the recipient. Accepts prompts like. It is categorised as a Write tool in the Telephony MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on voice_call_with_input? +

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

What risk level is voice_call_with_input? +

voice_call_with_input is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit voice_call_with_input? +

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

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

voice_call_with_input is provided by the Telephony MCP Server MCP server (vonage-community/telephony-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.