36 tools. 15 can modify or destroy data without limits.
4 destructive tools with no built-in limits. Policy required.
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Financial operations (create_call, create_incoming_phone_number, create_verification) can move real money. An agent caught in a loop could drain accounts before anyone notices.
Write operations (add_conversation_participant, create_conversation, create_function) modify state. Without rate limits, an agent can make hundreds of changes in seconds — faster than any human can review or revert.
Execute tools (create_deployment, create_execution) trigger processes with side effects. Builds, notifications, workflows — all fired without throttling.
Intercept sits between your agent and Twilio. Every tool call checked against your policy before it executes — so your agent can do its job without breaking things.
npx -y @policylayer/intercept scan -- npx -y @twilio-labs/mcp create_call:
rules:
- action: deny Financial tools should be explicitly enabled per use case, not open by default.
add_conversation_participant:
rules:
- rate_limit: 30/hour Prevents bulk unintended modifications from agents caught in loops.
check_verification:
rules:
- rate_limit: 60/minute Controls API costs and prevents retry loops from exhausting upstream rate limits.
Yes. The Twilio server exposes 4 financial tools including create_call, create_incoming_phone_number, create_verification. Without a policy, an autonomous agent can call these with no spend caps, no rate limits, and no approval flow. Intercept lets you block financial tools by default or set per-tool rate limits.
The Twilio server has 9 write tools including add_conversation_participant, create_conversation, create_function. Set rate limits in your policy file -- for example, rate_limit: 10/hour prevents an agent from making more than 10 modifications per hour. Intercept enforces this at the transport layer.
36 tools across 4 categories: Execute, Financial, Read, Write. 21 are read-only. 15 can modify, create, or delete data.
One line change. Instead of running the Twilio server directly, prefix it with Intercept: intercept -c twilio.yaml -- npx -y @@twilio-labs/mcp. Download a pre-built policy from policylayer.com/policies/twilio and adjust the limits to match your use case.
Starter policies available for each. Same risk classification, same one-command setup.
Set budgets, approvals, and hard limits across MCP servers.
npx -y @policylayer/intercept init