AI agents call list_files to retrieve information from Ancestry MCP without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
Listing files is a read-only operation with no side effects—it retrieves metadata about available files without modifying or deleting them. Within a genealogical data server, it poses minimal risk (low severity) as it only enumerates what files exist. Confidence is slightly reduced (0.85) due to missing description, but the function name and sibling context make the intent clear.
From the tool's definition Tool name 'list_files' indicates directory/file enumeration. Context shows server handles .ged files (genealogical data). Listed as sibling to 'view_file' and 'rename_file', suggesting file system operations.
Documented attack patterns abuse exactly the kind of access list_files gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Ancestry MCP, and nothing reaches the server without passing your rules. This is the rule we recommend for list_files:
{
"version": "1",
"default": "deny",
"tools": {
"list_files": {}
}
}list_files is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
Free to start. No card required.
list_files. It is categorised as a Read tool in the Ancestry MCP MCP Server, which means it retrieves data without modifying state.
Register the Ancestry MCP server in PolicyLayer and add a rule for list_files: 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 Ancestry MCP. Nothing to install.
list_files 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_files 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_files. 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_files is provided by the Ancestry MCP server (reeeeemo/ancestry-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 3 Ancestry MCP tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
3 Ancestry MCP tools catalogued and risk-classified — across an index of 42,500+ MCP servers.