twilio_send_sms · Integrations MCP: Risk & Policy

WHAT IT DOES

What twilio_send_sms does on Integrations MCP

AI agents invoke twilio_send_sms to trigger actions in Integrations MCP. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why twilio_send_sms needs a policy

Sending an SMS via Twilio triggers an external operation (message delivery to a phone number) that cannot be undone and may incur costs. The description is empty, so classification is based on the name alone. 'send' implies an outbound action with real-world side effects. While there is a minor financial dimension (Twilio charges per SMS), the primary risk is Execute (triggering external communications).

From the tool's definition Tool name 'twilio_send_sms' — Twilio is a communications platform; 'send_sms' indicates triggering an external SMS message delivery operation.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

twilio_send_sms Rate-limited

twilio_send_sms stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "twilio_send_sms": {
      "limits": [
        {
          "counter": "twilio_send_sms_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

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

FAQ

Questions about twilio_send_sms

What does the twilio_send_sms tool do? +

twilio_send_sms. It is categorised as a Execute tool in the Integrations MCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on twilio_send_sms? +

Register the Integrations MCP server in PolicyLayer and add a rule for twilio_send_sms: 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 Integrations MCP. Nothing to install.

What risk level is twilio_send_sms? +

twilio_send_sms is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit twilio_send_sms? +

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

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

twilio_send_sms is provided by the Integrations MCP server (shriram-vasudevan/integrations-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.