create_memento_relationship · MCP Memento MCP: Risk & Policy

WHAT IT DOES

What create_memento_relationship does on MCP Memento

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

WHY IT NEEDS A POLICY

Why create_memento_relationship needs a policy

The tool creates relationships between stored mementos (knowledge items) in a persistent memory system. This is a reversible write operation—relationships can be modified or deleted. No code execution, data destruction, or financial impact. The empty description and absence of destructive indicators suggest low severity; misuse would create spurious connections rather than cause system damage.

From the tool's definition Tool name contains 'create' which indicates data creation; context shows this is part of a memory/knowledge base system with relationship mapping capabilities. Description is empty, limiting evidence.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_memento_relationship Rate-limited

create_memento_relationship 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": {
    "create_memento_relationship": {
      "limits": [
        {
          "counter": "create_memento_relationship_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 MCP Memento, so you can run agents against it safely.

FAQ

Questions about create_memento_relationship

What does the create_memento_relationship tool do? +

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

How do I enforce a policy on create_memento_relationship? +

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

What risk level is create_memento_relationship? +

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

Can I rate-limit create_memento_relationship? +

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

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

create_memento_relationship is provided by the MCP Memento MCP server (x-hannibal/mcp-memento). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.