kusto_query · Kusto MCP Server MCP: Risk & Policy

WHAT IT DOES

What kusto_query does on Kusto MCP Server

AI agents invoke kusto_query to trigger actions in Kusto MCP 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 kusto_query needs a policy

While named 'query', this tool executes arbitrary KQL against a live Azure Data Explorer cluster. KQL can include management commands and data manipulation beyond read-only queries. The sibling tool 'kusto_execute' suggests this tool may still permit broad query execution.

From the tool's definition "Execute a KQL (Kusto Query Language) query against an Azure Data Explorer cluster" and "primary tool for running queries"

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

kusto_query Rate-limited

kusto_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": {
    "kusto_query": {
      "limits": [
        {
          "counter": "kusto_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 Kusto MCP Server, so you can run agents against it safely.

FAQ

Questions about kusto_query

What does the kusto_query tool do? +

Execute a KQL (Kusto Query Language) query against an Azure Data Explorer cluster. This is the primary tool for running queries. It is categorised as a Execute tool in the Kusto MCP 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 kusto_query? +

Register the Kusto MCP Server MCP server in PolicyLayer and add a rule for kusto_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 Kusto MCP Server. Nothing to install.

What risk level is kusto_query? +

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

Can I rate-limit kusto_query? +

Yes. Add a rate_limit block to the kusto_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 kusto_query completely? +

Set action: deny in the PolicyLayer policy for kusto_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 kusto_query? +

kusto_query is provided by the Kusto MCP Server MCP server (yeshsurya/kusto-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.