List serial ports with valid descriptions (not n/a).
AI agents call list_serial_ports to retrieve information from ESP-IDF FastMCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool queries and returns information about available serial ports on the system. It performs no modifications, deletions, or executions—it is a simple enumeration operation. Even if misused by an AI agent, it only exposes device information without capability to alter system state or perform operations.
From the tool's definition Tool name 'list_serial_ports' and description 'List serial ports with valid descriptions' indicate data retrieval with no side effects.
Attacks that exploit this kind of access
List serial ports with valid descriptions (not n/a). It is categorised as a Read tool in the ESP-IDF FastMCP Server MCP Server, which means it retrieves data without modifying state.
Register the ESP-IDF FastMCP Server MCP server in PolicyLayer and add a rule for list_serial_ports: 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 ESP-IDF FastMCP Server. Nothing to install.
list_serial_ports 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_serial_ports 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_serial_ports. 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_serial_ports is provided by the ESP-IDF FastMCP Server MCP server (jasper-zsh/espidf-mcp). 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.
Teams ship this data inside their own products. See what a licence covers →