fw_list_library

THE RISK

Low Risk

Why fw_list_library needs a policy

This tool queries and returns information about the currently authenticated user. It is a read-only operation that retrieves data without creating, modifying, deleting, or executing any actions. The blast radius is minimal as it only exposes user identity information to the requestor.

From the tool's definition Tool description states it 'List the authenticated user' - a retrieval operation with no modification or side effects.

Documented attack patterns abuse exactly the kind of access fw_list_library gives an agent:

POLICY

How to control fw_list_library

PolicyLayer is an MCP gateway — it sits between your AI agents and Crow, and nothing reaches the server without passing your rules. This is the rule we recommend for fw_list_library:

policy.json

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

fw_list_library is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.

Create a free account and register Crow — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

CAP THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More Crow tools

Financial crow_tax_prepare_from_documents One-step tax return preparation: creates a return from ALL confirmed documents uploaded th Financial crow_actual_create_transaction Create a new transaction. Amount in cents (negative = expense, positive = income). Financial crow_tax_set_capital_gains Add Schedule D capital gain/loss transactions. Destructive caddy_remove_site Remove a site block from the Caddyfile (matched by address) and reload Caddy. Destructive Destructive crow_bookstack_delete Delete a page or chapter from BookStack (irreversible) Destructive crow_campaign_delete Delete a campaign and all its posts. Requires confirmation. Destructive crow_crosspost_cancel Cancel a queued cross-post before its scheduled_at fires. Idempotent — cancelling an alrea Destructive crow_delete_context_section Delete a custom crow.md section. Protected sections cannot be deleted — only disabled. Sco

All 576 Crow tools →

Read tools on other servers

M-Team MCP Server get_torrent_detail YouTube MCP Server search_channel Android Forensics ADB MCP Server parse_browser_history 0xarchive web3_challenge

Go deeper

The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Data exfiltration → How read access becomes an exfiltration channel when chained with untrusted content.
MCP token cost → What connecting this server costs in context-window tokens on every request.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about fw_list_library

What does the fw_list_library tool do? +

List the authenticated user. It is categorised as a Read tool in the Crow MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on fw_list_library? +

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

What risk level is fw_list_library? +

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

Can I rate-limit fw_list_library? +

Yes. Add a rate_limit block to the fw_list_library 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 fw_list_library completely? +

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

fw_list_library is provided by the Crow MCP server (kh0pper/crow). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Crow tool call.

Start from Crow, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →