AI agents use add to create or update resources in MCPX MCP Gateway — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your MCPX MCP Gateway environment.
An AI agent can call add faster than any human can review — one bad instruction and it creates or modifies resources in MCPX MCP Gateway by the hundred, each call as confident as the last.
Documented attack patterns abuse exactly the kind of access add gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and MCPX MCP Gateway, and nothing reaches the server without passing your rules. This is the rule we recommend for add:
{
"version": "1",
"default": "deny",
"tools": {
"add": {
"limits": [
{
"counter": "add_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}add stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.
Free to start. No card required.
Adds two numbers together. It is categorised as a Write tool in the MCPX MCP Gateway MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the MCPX MCP Gateway MCP server in PolicyLayer and add a rule for add: 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 MCPX MCP Gateway. Nothing to install.
add is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the add 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 add. 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.
add is provided by the MCPX MCP Gateway MCP server (thelunarcompany/lunar). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 14 MCPX MCP Gateway tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
14 MCPX MCP Gateway tools catalogued and risk-classified — across an index of 42,500+ MCP servers.