datastore_query · MCP Datastore Server MCP: Risk & Policy

WHAT IT DOES

What datastore_query does on MCP Datastore Server

AI agents invoke datastore_query to trigger actions in MCP Datastore Server. 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 datastore_query needs a policy

While the server description frames this as a 'query' tool, the tool itself says 'Execute a query' with optional filters, meaning it actively runs parameterized queries against the datastore. This goes beyond a simple read/get operation and into the Execute category.

From the tool's definition "Execute a query on entities with optional filters" — the word 'Execute' and the ability to run arbitrary queries with filters indicates active query execution beyond simple retrieval.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

datastore_query Rate-limited

datastore_query 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": {
    "datastore_query": {
      "limits": [
        {
          "counter": "datastore_query_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 MCP Datastore Server, so you can run agents against it safely.

FAQ

Questions about datastore_query

What does the datastore_query tool do? +

Execute a query on entities with optional filters. It is categorised as a Execute tool in the MCP Datastore Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on datastore_query? +

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

What risk level is datastore_query? +

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

Can I rate-limit datastore_query? +

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

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

datastore_query is provided by the MCP Datastore Server MCP server (johnreitano/daisy). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.