# sms_cancel_scheduled

A destructive tool on the Twilio SMS MCP Server MCP server.

Agent View of the PolicyLayer registry record for `sms_cancel_scheduled`. HTML page: https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-cancel-scheduled

## Facts

- Tool: `sms_cancel_scheduled`
- Server: Twilio SMS MCP Server (`0x-professor/twilio-mcp-server`) — https://policylayer.com/tools/0x-professor-twilio-mcp-server.md
- Homepage: https://github.com/0x-Professor/Twilio-mcp-server
- Risk category: Destructive (Critical risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Hidden

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "sms_cancel_scheduled",
    "arguments": {}
  }
}
```

## Why sms_cancel_scheduled is rated Critical

Canceling a scheduled message is likely irreversible — once canceled, the scheduled send cannot be undone. The name strongly implies cancellation of a previously scheduled operation. Description is empty, which lowers confidence, but given the server context and naming convention, this is most likely a destructive/irreversible action.

From the tool's own definition: "Tool name 'sms_cancel_scheduled' on a server that handles scheduled SMS/MMS messaging; description is empty"

## Use case

AI agents call sms_cancel_scheduled to permanently remove resources in Twilio SMS MCP Server, typically in cleanup and lifecycle workflows. It does its job in a single call, and there is no undo.

## Recommended policy (PolicyLayer)

Verdict: **Hidden**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Twilio SMS MCP Server:

```json
{
  "version": "1",
  "default": "deny",
  "hide": [
    "sms_cancel_scheduled"
  ]
}
```

## Other tools on Twilio SMS MCP Server (15)

- `sms_delete_message` — Destructive — https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-delete-message.md
- `sms_account_info` — Read — https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-account-info.md
- `sms_format_number` — Read — https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-format-number.md
- `sms_get_conversation` — Read — https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-get-conversation.md
- `sms_get_message` — Read — https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-get-message.md
- `sms_list_inbox` — Read — https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-list-inbox.md
- `sms_list_numbers` — Read — https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-list-numbers.md
- `sms_list_sent` — Read — https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-list-sent.md
- `sms_lookup_number` — Read — https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-lookup-number.md
- `sms_redact_message` — Read — https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-redact-message.md
- `sms_usage_stats` — Read — https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-usage-stats.md
- `sms_mark_read` — Write — https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-mark-read.md
- `sms_schedule` — Write — https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-schedule.md
- `sms_send` — Write — https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-send.md
- `sms_send_bulk` — Write — https://policylayer.com/tools/0x-professor-twilio-mcp-server/sms-send-bulk.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=0x-professor-twilio-mcp-server · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/0x-professor-twilio-mcp-server