show-tables

THE RISK

Low Risk

Why show-tables needs a policy

This tool only enumerates metadata (table names) from the database without querying, modifying, or executing any data operations. It is a safe discovery/introspection operation with minimal blast radius even if called by an AI agent without restriction.

From the tool's definition Tool name is 'show-tables' and description states it 'List tables in the current database' — a pure retrieval operation with no modification or execution of queries against data.

Documented attack patterns abuse exactly the kind of access show-tables gives an agent:

POLICY

How to control show-tables

PolicyLayer is an MCP gateway — it sits between your AI agents and Kusto, and nothing reaches the server without passing your rules. This is the rule we recommend for show-tables:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "show-tables": {}
  }
}

show-tables is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.

Create a free account and register Kusto — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

CAP THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More Kusto tools

Execute execute-query Runs KQL queries and returns results. By default, limits results to 20 rows to prevent con Execute initialize-connection Creates connection to an ADX cluster Read show-function Show details of a specific function, including its code and parameters Read show-functions List functions in the current database Read show-table Show the table schema columns

All 6 Kusto tools →

Read tools on other servers

M-Team MCP Server get_torrent_detail YouTube MCP Server search_channel Android Forensics ADB MCP Server parse_browser_history 0xarchive web3_challenge

Go deeper

The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Data exfiltration → How read access becomes an exfiltration channel when chained with untrusted content.
MCP token cost → What connecting this server costs in context-window tokens on every request.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about show-tables

What does the show-tables tool do? +

List tables in the current database. It is categorised as a Read tool in the Kusto MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on show-tables? +

Register the Kusto MCP server in PolicyLayer and add a rule for show-tables: 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. Nothing to install.

What risk level is show-tables? +

show-tables is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit show-tables? +

Yes. Add a rate_limit block to the show-tables 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 show-tables completely? +

Set action: deny in the PolicyLayer policy for show-tables. 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 show-tables? +

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

Enforce policy on every Kusto tool call.

Start from Kusto, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →