Cancel or pause a scheduled send by batch_id via POST /user/scheduled_sends. A send_mail call with
AI agents use cancel_scheduled_send to commit financial operations through Mcp Ap2 — usually the final step of a payment, billing, or trading workflow. A call moves real money.
The server is explicitly a payment protocol (AP2 — Agent-to-Agent Payment Protocol). While the tool name 'cancel_scheduled_send' and the description referencing 'send_mail' and 'POST /user/scheduled_sends' could suggest email scheduling, in the context of this payment-focused server, scheduled sends most likely refer to scheduled financial transfers or payment instructions.
From the tool's definition cancel_scheduled_send on a server described as 'Google's Agent-to-Agent Payment Protocol (authorization, audit, trust)' with sibling tools like activate_subscription, add_bundle_deal suggesting financial operations; 'scheduled sends' in this context likely…
Documented attack patterns abuse exactly the kind of access cancel_scheduled_send gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Mcp Ap2, and nothing reaches the server without passing your rules. This is the rule we recommend for cancel_scheduled_send:
{
"version": "1",
"default": "deny",
"tools": {
"cancel_scheduled_send": {
"deny_if": [
{
"conditions": [],
"on_deny": "Requires human approval."
}
]
}
}
} Any call to cancel_scheduled_send is blocked until a human approves it. The rest of the server keeps working.
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Cancel or pause a scheduled send by batch_id via POST /user/scheduled_sends. A send_mail call with. It is categorised as a Financial tool in the Mcp Ap2 MCP Server, which means it involves financial transactions. Block by default and require explicit approval.
Register the Mcp Ap2 MCP server in PolicyLayer and add a rule for cancel_scheduled_send: 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 Mcp Ap2. Nothing to install.
cancel_scheduled_send is a Financial tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.
Yes. Add a rate_limit block to the cancel_scheduled_send 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.
Set action: deny in the PolicyLayer policy for cancel_scheduled_send. 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.
cancel_scheduled_send is provided by the Mcp Ap2 MCP server (@codespar/mcp-ap2). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Mcp Ap2, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
1300 Mcp Ap2 tools catalogued and risk-classified — across an index of 43,000+ MCP servers.