browser_upload_file · Amazon MQ MCP Server MCP

WHAT IT DOES

What browser_upload_file does on Amazon MQ MCP Server

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

WHY IT NEEDS A POLICY

Why browser_upload_file needs a policy

File upload operations create or modify data in a system, placing this in the Write category. Severity is medium because unvalidated file uploads could lead to stored malicious content or resource exhaustion, but without knowing the validation, storage location, or whether deletion is possible, it does not rise to Destructive or critical.

From the tool's definition Tool name 'browser_upload_file' indicates file upload functionality. The empty description prevents confident categorization of the upload target and side effects.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

browser_upload_file Rate-limited

browser_upload_file 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": {
    "browser_upload_file": {
      "limits": [
        {
          "counter": "browser_upload_file_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 Amazon MQ MCP Server, so you can run agents against it safely.

FAQ

Questions about browser_upload_file

What does the browser_upload_file tool do? +

browser_upload_file. It is categorised as a Write tool in the Amazon MQ 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 browser_upload_file? +

Register the Amazon MQ MCP Server MCP server in PolicyLayer and add a rule for browser_upload_file: 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 Amazon MQ MCP Server. Nothing to install.

What risk level is browser_upload_file? +

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

Can I rate-limit browser_upload_file? +

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

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

browser_upload_file is provided by the Amazon MQ MCP Server MCP server (awslabs.amazon-mq-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.