query_memory · Structured-sh MCP: Risk & Policy

WHAT IT DOES

What query_memory does on Structured-sh

AI agents invoke query_memory to trigger actions in Structured-sh. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why query_memory needs a policy

This tool executes arbitrary DuckDB SQL queries, making it Execute category. While the example shows a SELECT, arbitrary SQL can include DELETE, DROP, UPDATE, or other destructive statements. The blast radius is high because a misused query could corrupt or destroy persistent memory state across sessions and tools, and the open-ended SQL execution surface is significant.

From the tool's definition "Run a DuckDB SQL query across memories" — executes arbitrary SQL, which can include destructive or read operations depending on the query

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

query_memory Rate-limited

query_memory stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "query_memory": {
      "limits": [
        {
          "counter": "query_memory_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Structured-sh, so you can run agents against it safely.

FAQ

Questions about query_memory

What does the query_memory tool do? +

Run a DuckDB SQL query across memories. Use memory names as table names. Example: SELECT * FROM user_preferences WHERE key = \. It is categorised as a Execute tool in the Structured-sh MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on query_memory? +

Register the Structured-sh MCP server in PolicyLayer and add a rule for query_memory: 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 Structured-sh. Nothing to install.

What risk level is query_memory? +

query_memory is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit query_memory? +

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

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

query_memory is provided by the Structured-sh MCP server (structured-sh/structured). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.