memvid_lock · Memvid MCP: Risk & Policy

WHAT IT DOES

What memvid_lock does on Memvid

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

WHY IT NEEDS A POLICY

Why memvid_lock needs a policy

This tool creates a new encrypted file from an existing memory file, which is a reversible data modification operation. It does not delete, destroy, or execute arbitrary code, but does write new data to disk. The operation is reversible (the original .mv2 file remains unchanged, and the encrypted file could be decrypted or deleted).

From the tool's definition Tool creates an encrypted .mv2e file using AES-256-GCM encryption. Description states 'Creates an encrypted .mv2e file' and 'output path for the encrypted file (.mv2e)', indicating new file creation/modification.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

memvid_lock Rate-limited

memvid_lock 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": {
    "memvid_lock": {
      "limits": [
        {
          "counter": "memvid_lock_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 Memvid, so you can run agents against it safely.

FAQ

Questions about memvid_lock

What does the memvid_lock tool do? +

Encrypt a memory file. Creates an encrypted .mv2e file using AES-256-GCM encryption. The original .mv2 file is not modified. Args: file: Path to the .mv2 file to encrypt output: Output path for the encrypted file (.mv2e) password: Encryption password (required for non-interactive use) Returns: {. It is categorised as a Write tool in the Memvid MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on memvid_lock? +

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

What risk level is memvid_lock? +

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

Can I rate-limit memvid_lock? +

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

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

memvid_lock is provided by the Memvid MCP server (tapiocapioca/memvid-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.