cairntir_remember · Cairntir MCP: Risk & Policy

WHAT IT DOES

What cairntir_remember does on Cairntir

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

WHY IT NEEDS A POLICY

Why cairntir_remember needs a policy

This tool writes new memory entries into the local SQLite database. It creates data persistently but is reversible (memories can presumably be deleted or overwritten). The blast radius is medium because a misused AI agent could pollute the memory store with false or misleading information that persists across sessions, affecting future context-aware conversations.

From the tool's definition "Store a verbatim memory drawer" — creates/writes data to the SQLite memory system

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

cairntir_remember Rate-limited

cairntir_remember 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": {
    "cairntir_remember": {
      "limits": [
        {
          "counter": "cairntir_remember_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 Cairntir, so you can run agents against it safely.

FAQ

Questions about cairntir_remember

What does the cairntir_remember tool do? +

Store a verbatim memory drawer in a wing/room. It is categorised as a Write tool in the Cairntir MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on cairntir_remember? +

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

What risk level is cairntir_remember? +

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

Can I rate-limit cairntir_remember? +

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

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

cairntir_remember is provided by the Cairntir MCP server (pnmcguire480/cairntir). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.