memory_add_rule · Claude Memory MCP: Risk & Policy

WHAT IT DOES

What memory_add_rule does on Claude Memory MCP

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

WHY IT NEEDS A POLICY

Why memory_add_rule needs a policy

This tool creates or modifies configuration data (rules) persistently. It does not retrieve data (Read), execute arbitrary code (Execute), irreversibly destroy data (Destructive), or move money (Financial). It is a Write operation because it adds records that can be later modified or deleted.

From the tool's definition Tool name: 'memory_add_rule'. Description: 'Add a project rule' — this creates a new rule record in the memory system, modifying the project's stored configuration. The operation is reversible via memory_delete_rule.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

memory_add_rule Rate-limited

memory_add_rule 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": {
    "memory_add_rule": {
      "limits": [
        {
          "counter": "memory_add_rule_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 Claude Memory MCP, so you can run agents against it safely.

FAQ

Questions about memory_add_rule

What does the memory_add_rule tool do? +

Add a project rule. rule_type is 'mandatory' (always do) or 'forbidden'. It is categorised as a Write tool in the Claude Memory MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on memory_add_rule? +

Register the Claude Memory MCP server in PolicyLayer and add a rule for memory_add_rule: 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 Claude Memory MCP. Nothing to install.

What risk level is memory_add_rule? +

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

Can I rate-limit memory_add_rule? +

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

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

memory_add_rule is provided by the Claude Memory MCP server (navid-kianfar/claude-memory-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.