list_losers

List losing Creative Specs for a product = the NEGATIVE lesson set, what NOT to do. Read the caveats:

SERVERAd Lab SOURCE@577-tools/ad-lab-mcp

Low RISK CLASS

Category Read

Parameters 00 required

Recommended Allowedsee the rule below

Registry record Grade C, identity unverified Pull the record →

This record as markdown: /tools/577-tools-ad-lab-mcp/list-losers.md

WHAT IT DOES

What list_losers does on Ad Lab

AI agents call list_losers to retrieve information from Ad Lab without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

RISK

Why list_losers is rated Low

Even though list_losers only reads data, uncontrolled read access leaks sensitive information and racks up API costs: an agent caught in a retry loop can make thousands of calls a minute without anyone noticing.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs list_losers safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Ad Lab, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For list_losers, this is the rule to start with:

list_losers Allowed

list_losers is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "list_losers": {}
  }
}

ALLOW ONLY THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Ad Lab, apply this rule, and every list_losers call is checked against it from then on.

FAQ

Questions about list_losers

What does the list_losers tool do? +

List losing Creative Specs for a product = the NEGATIVE lesson set, what NOT to do. Read the caveats:. It is categorised as a Read tool in the Ad Lab MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on list_losers? +

Register the Ad Lab MCP server in PolicyLayer and add a rule for list_losers: 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 Ad Lab. Nothing to install.

What risk level is list_losers? +

list_losers is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit list_losers? +

Yes. Add a rate_limit block to the list_losers 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.

How do I block list_losers completely? +

Set action: deny in the PolicyLayer policy for list_losers. 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.

What MCP server provides list_losers? +

list_losers is provided by the Ad Lab MCP server (@577-tools/ad-lab-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

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