discord.message.send

THE RISK

Medium Risk

Why discord.message.send needs a policy

This tool creates new messages in a Discord channel, which is a Write operation (reversible in the sense that messages can be deleted). The dry-run default slightly reduces immediate risk, but if invoked in live mode, an AI agent could send arbitrary messages to potentially large audiences.

From the tool's definition 'Send a message to a Discord channel. Defaults to dry-run mode.'

Documented attack patterns abuse exactly the kind of access discord.message.send gives an agent:

POLICY

How to control discord.message.send

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

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "discord.message.send": {
      "limits": [
        {
          "counter": "discord.message.send_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

discord.message.send 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 Discord MCP Server — 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 Discord MCP Server tools

All 45 Discord MCP Server 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 discord.message.send

What does the discord.message.send tool do? +

Send a message to a Discord channel. Defaults to dry-run mode. It is categorised as a Write tool in the Discord MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on discord.message.send? +

Register the Discord MCP Server MCP server in PolicyLayer and add a rule for discord.message.send: 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 Discord MCP Server. Nothing to install.

What risk level is discord.message.send? +

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

Can I rate-limit discord.message.send? +

Yes. Add a rate_limit block to the discord.message.send 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 discord.message.send completely? +

Set action: deny in the PolicyLayer policy for discord.message.send. 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 discord.message.send? +

discord.message.send is provided by the Discord MCP Server MCP server (rastrian/discordmcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Discord MCP Server tool call.

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

CHECK YOUR STACK →