AI agents invoke execute_api to trigger actions in Mcp Api Gateway. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.
This tool can invoke arbitrary API endpoints with attacker-controlled parameters, potentially triggering unintended side effects (data modification, deletion, financial transactions, or external system state changes) depending on what endpoints are exposed by the underlying OpenAPI spec.
From the tool's definition Tool named 'execute_api' with description 'Execute any API endpoint with custom parameters' — the verb 'execute' combined with 'any API endpoint' and 'custom parameters' indicates the ability to trigger arbitrary external operations whose effects depend on…
Documented attack patterns abuse exactly the kind of access execute_api gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Mcp Api Gateway, and nothing reaches the server without passing your rules. This is the rule we recommend for execute_api:
{
"version": "1",
"default": "deny",
"tools": {
"execute_api": {
"limits": [
{
"counter": "execute_api_rate",
"window": "minute",
"max": 10,
"scope": "grant"
}
]
}
}
}execute_api stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.
Free to start. No card required.
Execute any API endpoint with custom parameters. It is categorised as a Execute tool in the Mcp Api Gateway MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the Mcp Api Gateway MCP server in PolicyLayer and add a rule for execute_api: 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 Api Gateway. Nothing to install.
execute_api is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.
Yes. Add a rate_limit block to the execute_api 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 execute_api. 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.
execute_api is provided by the Mcp Api Gateway MCP server (rflpazini/mcp-api-gateway). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 3 Mcp Api Gateway tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
3 Mcp Api Gateway tools catalogued and risk-classified — across an index of 42,500+ MCP servers.