dns_reverse

Reverse DNS lookup — find hostnames for an IP address.

SERVERJshookmcp SOURCE@jshookmcp/jshook

Low RISK CLASS

Category Read

Parameters 00 required

Recommended Allowedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/io-github-vmoranv-jshookmcp/dns-reverse.md

WHAT IT DOES

What dns_reverse does on Jshookmcp

AI agents call dns_reverse to retrieve information from Jshookmcp without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

RISK

Why dns_reverse is rated Low

Queries DNS records without modifying data or triggering external operations with side effects.

From the tool's definition Reverse DNS lookup — find hostnames for an IP address

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs dns_reverse safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Jshookmcp, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For dns_reverse, this is the rule to start with:

dns_reverse Allowed

dns_reverse is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "dns_reverse": {}
  }
}

ALLOW ONLY THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Jshookmcp, apply this rule, and every dns_reverse call is checked against it from then on.

FAQ

Questions about dns_reverse

What does the dns_reverse tool do? +

Reverse DNS lookup — find hostnames for an IP address. It is categorised as a Read tool in the Jshookmcp MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on dns_reverse? +

Register the Jshook MCP server in PolicyLayer and add a rule for dns_reverse: 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 Jshookmcp. Nothing to install.

What risk level is dns_reverse? +

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

Can I rate-limit dns_reverse? +

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

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

dns_reverse is provided by the Jshook MCP server (@jshookmcp/jshook). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

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