Check if an app exists on the Faber server and get its details
AI agents call faber_check_app to retrieve information from Faber MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool performs a read-only operation—checking app existence and fetching its details. It has no capability to modify, delete, deploy, or execute code. The blast radius of misuse is minimal; an agent querying app details poses no significant risk. Classified as Read with low severity.
From the tool's definition Tool name 'faber_check_app' and description 'Check if an app exists on the Faber server and get its details' indicates a query operation that retrieves application metadata without modification or side effects.
Attacks that exploit this kind of access
Check if an app exists on the Faber server and get its details. It is categorised as a Read tool in the Faber MCP Server MCP Server, which means it retrieves data without modifying state.
Register the Faber MCP Server MCP server in PolicyLayer and add a rule for faber_check_app: 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 Faber MCP Server. Nothing to install.
faber_check_app 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 faber_check_app 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 faber_check_app. 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.
faber_check_app is provided by the Faber MCP Server MCP server (joshtrebilco/faber-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 →