List all top-level concepts in the knowledge graph with their direct children. Call this at the start of a session to get a high-level project overview.
AI agents call list_roots to retrieve information from MegaMemory without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves and displays existing data from the knowledge graph without creating, modifying, deleting, or executing anything. It is purely informational, making it a Read operation with low severity since unauthorized access to project structure information poses minimal direct risk.
From the tool's definition Tool name 'list_roots' and description 'List all top-level concepts' indicate retrieval/querying of data. The phrase 'get a high-level project overview' confirms read-only introspection with no modifications or side effects.
Documented attack patterns abuse exactly the kind of access list_roots gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and MegaMemory, and nothing reaches the server without passing your rules. This is the rule we recommend for list_roots:
{
"version": "1",
"default": "deny",
"tools": {
"list_roots": {}
}
}list_roots is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
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List all top-level concepts in the knowledge graph with their direct children. Call this at the start of a session to get a high-level project overview. It is categorised as a Read tool in the MegaMemory MCP Server, which means it retrieves data without modifying state.
Register the MegaMemory MCP server in PolicyLayer and add a rule for list_roots: 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 MegaMemory. Nothing to install.
list_roots 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_roots 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_roots. 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_roots is provided by the MegaMemory MCP server (0xk3vin/megamemory). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 9 MegaMemory tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
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9 MegaMemory tools catalogued and risk-classified — across an index of 42,500+ MCP servers.