AI agents call check_fcrdns to retrieve information from Intodns without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool queries DNS infrastructure to verify FCrDNS records (checking that forward and reverse DNS match). It retrieves and analyzes existing DNS data without modifying, executing code, deleting, or affecting any systems. The 'read-only' qualifier and 'audit' context confirm purely observational security analysis.
From the tool's definition Tool name and description explicitly state 'Read-only' and 'audit' functionality for DNS reverse lookups. The description confirms it performs information retrieval without side effects: 'FCrDNS (Forward-Confirmed Reverse DNS) audit for every IP that backs…
Risk signalsBulk/mass operation — affects multiple targets
Attacks that exploit this kind of access
Read-only FCrDNS (Forward-Confirmed Reverse DNS) audit for every IP that backs the domain. It is categorised as a Read tool in the Intodns MCP Server, which means it retrieves data without modifying state.
Register the Intodns MCP server in PolicyLayer and add a rule for check_fcrdns: 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 Intodns. Nothing to install.
check_fcrdns is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the check_fcrdns 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.
Set action: deny in the PolicyLayer policy for check_fcrdns. 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.
check_fcrdns is provided by the Intodns MCP server (rosconl/intodns-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Every MCP server has a record like this.
Type a name, get the same breakdown: verified identity, auth posture, risk grade, capabilities, recommended policy.
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