check_sip

SERVERMcp Nettools SOURCEaaronckj/mcp-nettools

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/aaronckj-mcp-nettools/check-sip.md

WHAT IT DOES

What check_sip does on Mcp Nettools

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

RISK

Why check_sip is rated Low

This tool sends a read-only OPTIONS probe to a SIP server and returns status information. It does not modify, delete, or create any data, and has no financial implications. It is purely a diagnostic/health-check operation.

From the tool's definition Check a SIP (Session Initiation Protocol) server by sending an OPTIONS probe... Returns whether the server is reachable and responds with a valid SIP message. Useful for verifying VoIP server health.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs check_sip safely

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

check_sip Allowed

check_sip 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": {
    "check_sip": {}
  }
}

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

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

FAQ

Questions about check_sip

What does the check_sip tool do? +

Check a SIP (Session Initiation Protocol) server by sending an OPTIONS probe. port: default 5060 (UDP/TCP) or 5061 (TLS). transport: 'udp' (default) or 'tcp'. Returns whether the server is reachable and responds with a valid SIP message. Useful for verifying VoIP server health. It is categorised as a Read tool in the Mcp Nettools MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on check_sip? +

Register the Mcp Nettools MCP server in PolicyLayer and add a rule for check_sip: 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 Nettools. Nothing to install.

What risk level is check_sip? +

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

Can I rate-limit check_sip? +

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

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

check_sip is provided by the Mcp Nettools MCP server (aaronckj/mcp-nettools). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

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