Register a fiat receiver account (BRL Pix, USD wire, EUR SEPA, MXN SPEI). Skippable for BRL Pix payouts — pass pix_key + document directly on /payout instead.
AI agents use create_external_account to commit financial operations through Mcp Ap2 — usually the final step of a payment, billing, or trading workflow. A call moves real money.
This tool registers external bank/payment accounts for receiving real money transfers across multiple fiat currencies and payment rails (Pix, wire, SEPA, SPEI). It is clearly financial in nature — establishing the destination for money movement. Misuse could redirect funds to attacker-controlled accounts, making it critical severity.
From the tool's definition Register a fiat receiver account (BRL Pix, USD wire, EUR SEPA, MXN SPEI)
Documented attack patterns abuse exactly the kind of access create_external_account 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 create_external_account:
{
"version": "1",
"default": "deny",
"tools": {
"create_external_account": {
"deny_if": [
{
"conditions": [],
"on_deny": "Requires human approval."
}
]
}
}
} Any call to create_external_account is blocked until a human approves it. The rest of the server keeps working.
Free to start. No card required.
Register a fiat receiver account (BRL Pix, USD wire, EUR SEPA, MXN SPEI). Skippable for BRL Pix payouts — pass pix_key + document directly on /payout instead. 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 create_external_account: 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.
create_external_account 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 create_external_account 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 create_external_account. 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.
create_external_account 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.