MCP Tool Reference Medium Risk

send_message

Send an SMS or MMS message

Part of the Twilio MCP server. Enforce policies on this tool with Intercept, the open-source MCP proxy.

twilio-labs/mcp Write

WHEN AI AGENTS USE THIS TOOL

AI agents use send_message to create or modify resources in Twilio. Write operations carry medium risk because an autonomous agent could trigger bulk unintended modifications. Rate limits prevent a single agent session from making hundreds of changes in rapid succession. Argument validation ensures the agent passes expected values.

WHY ENFORCE A POLICY ON SEND_MESSAGE

Without a policy, an AI agent could call send_message repeatedly, creating or modifying resources faster than any human could review. Intercept's rate limiting ensures write operations happen at a controlled pace, and argument validation catches malformed or unexpected inputs before they reach Twilio.

RECOMMENDED POLICY

Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.

twilio.yaml 
tools:
  send_message:
    rules:
      - action: allow
        rate_limit:
          max: 30
          window: 60

See the full Twilio policy for all 36 tools.

DETAILS

Tool Name

send_message

Category

Write

MCP Server

Twilio MCP Server

Risk Level

Medium

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SIMILAR WRITE TOOLS ON OTHER SERVERS

create_table Airtable
Create a new table with fields
update_table Airtable
Update a table's name or description
create_field Airtable
Add a new field to a table
update_field Airtable
Modify an existing field
create_record Airtable
Add a new record
update_record Airtable
Modify an existing record

RELATED READING

FREQUENTLY ASKED QUESTIONS

What does the send_message tool do?

Send an SMS or MMS message. It is categorised as a Write tool in the Twilio MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on send_message?

Add a rule in your Intercept YAML policy under the tools section for send_message. You can allow, deny, rate-limit, or validate arguments. Then run Intercept as a proxy in front of the Twilio MCP server.

What risk level is send_message?

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

Can I rate-limit send_message?

Yes. Add a rate_limit block to the send_message rule in your Intercept 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 send_message completely?

Set action: deny in the Intercept policy for send_message. 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 send_message?

send_message is provided by the Twilio MCP server (twilio-labs/mcp). Intercept sits as a proxy in front of this server to enforce policies before tool calls reach the server.

ENFORCE POLICIES ON TWILIO

Open source. One binary. Zero dependencies.

VIEW ON GITHUB Full Twilio policy →