list_known_faces

List all known faces in the system.

SERVERAos SOURCE@hybridlabor-api/aos

Low RISK CLASS

Category Read

Parameters 00 required

Recommended Allowedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/hybridlabor-api-aos/list-known-faces.md

WHAT IT DOES

What list_known_faces does on Aos

AI agents call list_known_faces to retrieve information from Aos without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

RISK

Why list_known_faces is rated Low

Retrieves face data without modification, side effects, or access restrictions.

From the tool's definition List all known faces in the system.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs list_known_faces safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Aos, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For list_known_faces, this is the rule to start with:

list_known_faces Allowed

list_known_faces is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "list_known_faces": {}
  }
}

ALLOW ONLY THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Aos, apply this rule, and every list_known_faces call is checked against it from then on.

FAQ

Questions about list_known_faces

What does the list_known_faces tool do? +

List all known faces in the system. It is categorised as a Read tool in the Aos MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on list_known_faces? +

Register the Aos MCP server in PolicyLayer and add a rule for list_known_faces: 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 Aos. Nothing to install.

What risk level is list_known_faces? +

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

Can I rate-limit list_known_faces? +

Yes. Add a rate_limit block to the list_known_faces 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_known_faces completely? +

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

list_known_faces is provided by the Aos MCP server (@hybridlabor-api/aos). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

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