stage_media · WhatsApp MCP Stream MCP: Risk & Policy

WHAT IT DOES

What stage_media does on WhatsApp MCP Stream

AI agents use stage_media to create or update resources in WhatsApp MCP Stream — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your WhatsApp MCP Stream environment.

WHY IT NEEDS A POLICY

Why stage_media needs a policy

This tool creates or stores files on the server, which is a reversible write operation. It does not delete data (would be Destructive), execute code (would be Execute), or move money (would be Financial). The severity is medium rather than high because file staging is typically reversible and the blast radius depends on what files are staged and how they're subsequently used.

From the tool's definition Tool name 'stage_media' with description 'Save a file to the server' indicates creation/modification of files on the server storage.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

stage_media Rate-limited

stage_media 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.

View as policy code

policy.json

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

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches WhatsApp MCP Stream, so you can run agents against it safely.

FAQ

Questions about stage_media

What does the stage_media tool do? +

Save a file to the server. It is categorised as a Write tool in the WhatsApp MCP Stream MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on stage_media? +

Register the WhatsApp MCP Stream MCP server in PolicyLayer and add a rule for stage_media: 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 WhatsApp MCP Stream. Nothing to install.

What risk level is stage_media? +

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

Can I rate-limit stage_media? +

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

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

stage_media is provided by the WhatsApp MCP Stream MCP server (loglux/whatsapp-mcp-stream). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.