add_rule_to_policy · Privy MCP Server MCP: Risk & Policy

WHAT IT DOES

What add_rule_to_policy does on Privy MCP Server

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

WHY IT NEEDS A POLICY

Why add_rule_to_policy needs a policy

This tool creates or modifies policy rules, which is a Write operation (reversible data modification). It is not Destructive because rules can be updated or removed. It is not Execute because it doesn't directly run transactions or code.

From the tool's definition Tool description states 'Adds a new rule to an existing policy.' The server context involves blockchain operations, wallet management, and transaction signing.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

add_rule_to_policy Rate-limited

add_rule_to_policy 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": {
    "add_rule_to_policy": {
      "limits": [
        {
          "counter": "add_rule_to_policy_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 Privy MCP Server, so you can run agents against it safely.

FAQ

Questions about add_rule_to_policy

What does the add_rule_to_policy tool do? +

Adds a new rule to an existing policy. It is categorised as a Write tool in the Privy MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on add_rule_to_policy? +

Register the Privy MCP Server MCP server in PolicyLayer and add a rule for add_rule_to_policy: 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 Privy MCP Server. Nothing to install.

What risk level is add_rule_to_policy? +

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

Can I rate-limit add_rule_to_policy? +

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

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

add_rule_to_policy is provided by the Privy MCP Server MCP server (privy-io/privy-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.