scan_news · Metis Public Health MCP: Risk & Policy

WHAT IT DOES

What scan_news does on Metis Public Health

AI agents use scan_news to create or update resources in Metis Public Health — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Metis Public Health environment.

WHY IT NEEDS A POLICY

Why scan_news needs a policy

The tool both fetches data (Read) and adds new items to a data store (news_briefs), making Write the dominant category. Since it creates new records in the system, Write is appropriate. Severity is medium because it modifies the local data store with external content, which could introduce unwanted or malicious content if feeds are compromised.

From the tool's definition 'Fetch RSS feeds and add new items to news_briefs'

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

scan_news Rate-limited

scan_news 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": {
    "scan_news": {
      "limits": [
        {
          "counter": "scan_news_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 Metis Public Health, so you can run agents against it safely.

FAQ

Questions about scan_news

What does the scan_news tool do? +

Fetch RSS feeds and add new items to news_briefs. It is categorised as a Write tool in the Metis Public Health MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on scan_news? +

Register the Metis Public Health MCP server in PolicyLayer and add a rule for scan_news: 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 Metis Public Health. Nothing to install.

What risk level is scan_news? +

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

Can I rate-limit scan_news? +

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

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

scan_news is provided by the Metis Public Health MCP server (sveritg/metis_ph). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.