List the top-N MCP servers, ranked by composite quality score (default), raw GitHub stars, or real-world Smithery usage. Optional category filter.
AI agents call list_top to retrieve information from Mcpcatalogs without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This is a pure data retrieval operation that queries and returns a ranked list of MCP servers from a directory. It performs no writes, deletions, code execution, or financial transactions. The blast radius of misuse is minimal—an AI agent could only retrieve and compare server information, which poses no meaningful security risk.
From the tool's definition Tool description explicitly states 'List the top-N MCP servers' and retrieves ranked data with optional filtering. No modification, deletion, execution, or financial operations are mentioned.
Attacks that exploit this kind of access
List the top-N MCP servers, ranked by composite quality score (default), raw GitHub stars, or real-world Smithery usage. Optional category filter. It is categorised as a Read tool in the Mcpcatalogs MCP Server, which means it retrieves data without modifying state.
Register the Mcpcatalogs MCP server in PolicyLayer and add a rule for list_top: 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 Mcpcatalogs. Nothing to install.
list_top 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 list_top 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 list_top. 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.
list_top is provided by the Mcpcatalogs MCP server (mcpcatalogs/mcpcatalogs). 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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