pf_mute_user

THE RISK

Medium Risk

Why pf_mute_user needs a policy

Muting a user is a reversible write action that modifies account settings to suppress visibility of posts. It does not delete data or execute code. The rate limit suggests it affects account state persistently but can be undone (unmuted). Misuse could affect multiple accounts within the rate limit window, raising severity to medium.

From the tool's definition Mute an account (hide posts but still federate)

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

POLICY

How to control pf_mute_user

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 pf_mute_user:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "pf_mute_user": {
      "limits": [
        {
          "counter": "pf_mute_user_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

pf_mute_user stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. 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.

LIMIT 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 →

Write tools on other servers

M-Team MCP Server download_torrent YouTube MCP Server generate_video_title Android Forensics ADB MCP Server combine_reports 0xarchive web3_signup

Go deeper

The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Argument validation → Checking tool call arguments against schema and policy before they run.
Scoped token → Per-person credentials that grant a defined subset of servers and tools.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about pf_mute_user

What does the pf_mute_user tool do? +

Mute an account (hide posts but still federate). Rate-limited: 5/hour. It is categorised as a Write tool in the Crow MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on pf_mute_user? +

Register the Crow MCP server in PolicyLayer and add a rule for pf_mute_user: 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 pf_mute_user? +

pf_mute_user is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit pf_mute_user? +

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

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

pf_mute_user 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 →