store_data · Store MCP Server MCP: Risk & Policy

WHAT IT DOES

What store_data does on Store MCP Server

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

WHY IT NEEDS A POLICY

Why store_data needs a policy

This tool writes data persistently to a key-value store. It creates or overwrites entries but does not irreversibly destroy data (deletion is handled by a sibling tool). Misuse could lead to data corruption or overwriting of important stored information, warranting a medium severity.

From the tool's definition 'Store information with a key. The value can be any JSON-serializable data.' — creates or modifies persistent key-value entries in JSON file-based storage.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

store_data Rate-limited

store_data 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": {
    "store_data": {
      "limits": [
        {
          "counter": "store_data_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 Store MCP Server, so you can run agents against it safely.

FAQ

Questions about store_data

What does the store_data tool do? +

Store information with a key. The value can be any JSON-serializable data. It is categorised as a Write tool in the Store MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on store_data? +

Register the Store MCP Server MCP server in PolicyLayer and add a rule for store_data: 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 Store MCP Server. Nothing to install.

What risk level is store_data? +

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

Can I rate-limit store_data? +

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

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

store_data is provided by the Store MCP Server MCP server (mariano-cecowski/store_mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.