list_registered_children

WHAT IT DOES

What list_registered_children does on MCP Gateway (Parent MCP Server)

AI agents call list_registered_children to retrieve information from MCP Gateway (Parent MCP Server) without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

WHY IT NEEDS A POLICY

Why list_registered_children needs a policy

This tool retrieves metadata about registered child servers without modifying, deleting, or executing anything. It simply lists available servers, making it a straightforward read operation with minimal security risk.

From the tool's definition Tool description states '登録されている子MCPサーバーの名前一覧を取得します' (get a list of names of registered child MCP servers). The term '取得' (get/retrieve) combined with 'list_registered_children' indicates a read-only query operation with no side effects.

Attacks that exploit this kind of access

Questions about list_registered_children

What does the list_registered_children tool do? +

登録されている子MCPサーバーの名前一覧を取得します。. It is categorised as a Read tool in the MCP Gateway (Parent MCP Server) MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on list_registered_children? +

Register the MCP Gateway (Parent MCP Server) MCP server in PolicyLayer and add a rule for list_registered_children: 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 Gateway (Parent MCP Server). Nothing to install.

What risk level is list_registered_children? +

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

Can I rate-limit list_registered_children? +

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

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

list_registered_children is provided by the MCP Gateway (Parent MCP Server) MCP server (tomcat2357/mcpgateway). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.