memory_save · Mono Memory MCP: Risk & Policy

WHAT IT DOES

What memory_save does on Mono Memory MCP

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

WHY IT NEEDS A POLICY

Why memory_save needs a policy

The 'memory_save' function creates or modifies data in a shared SQLite database in a reversible manner. An AI agent misusing this could pollute the shared knowledge base with incorrect context or decisions, affecting team alignment and downstream tool decisions, but the impact is recoverable through edits or deletion.

From the tool's definition Tool name 'memory_save' strongly implies writing/persisting data to the SQLite-backed memory store. The server description establishes this is a persistent storage system for 'storing and retrieving project context, decisions, and discoveries.' The empty…

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

memory_save Rate-limited

memory_save 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_save": {
      "limits": [
        {
          "counter": "memory_save_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 Mono Memory MCP, so you can run agents against it safely.

FAQ

Questions about memory_save

What does the memory_save tool do? +

memory_save. It is categorised as a Write tool in the Mono 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_save? +

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

What risk level is memory_save? +

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

Can I rate-limit memory_save? +

Yes. Add a rate_limit block to the memory_save 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_save completely? +

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

memory_save is provided by the Mono Memory MCP server (potato-castle/mono-memory-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.