close_market · Manifold MCP: Risk & Policy

WHAT IT DOES

What close_market does on Manifold

AI agents use close_market to create or update resources in Manifold — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Manifold environment.

WHY IT NEEDS A POLICY

Why close_market needs a policy

Closing a market modifies its operational status irreversibly in terms of preventing trading, but the action itself is reversible (a market can potentially be reopened or its state adjusted by authorized operators). This distinguishes it from Destructive actions that permanently erase data.

From the tool's definition Tool named 'close_market' with description 'Close a market for trading' indicates modification of market state that prevents further trading activity.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

close_market Rate-limited

close_market 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.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "close_market": {
      "limits": [
        {
          "counter": "close_market_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Manifold, so you can run agents against it safely.

FAQ

Questions about close_market

What does the close_market tool do? +

Close a market for trading. It is categorised as a Write tool in the Manifold MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on close_market? +

Register the Manifold MCP server in PolicyLayer and add a rule for close_market: 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 Manifold. Nothing to install.

What risk level is close_market? +

close_market is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit close_market? +

Yes. Add a rate_limit block to the close_market 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 close_market completely? +

Set action: deny in the PolicyLayer policy for close_market. 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 close_market? +

close_market is provided by the Manifold MCP server (manifold-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.