mark-as-read · Outlook MCP Server MCP: Risk & Policy

WHAT IT DOES

What mark-as-read does on Outlook MCP Server

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

WHY IT NEEDS A POLICY

Why mark-as-read needs a policy

Marking an email as read/unread is a state modification operation that changes email properties. While non-destructive and reversible (can toggle back and forth), it goes beyond passive reading to actively alter data state, placing it in the Write category rather than Read. The blast radius is minimal since the action only affects email metadata flags and can be easily undone.

From the tool's definition Tool description states 'Marks an email as read or unread' — this modifies email metadata (read status) but does not create, delete, or permanently alter the email content itself. The operation is reversible.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

mark-as-read Rate-limited

mark-as-read 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": {
    "mark-as-read": {
      "limits": [
        {
          "counter": "mark-as-read_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 Outlook MCP Server, so you can run agents against it safely.

FAQ

Questions about mark-as-read

What does the mark-as-read tool do? +

Marks an email as read or unread. It is categorised as a Write tool in the Outlook 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 mark-as-read? +

Register the Outlook MCP Server MCP server in PolicyLayer and add a rule for mark-as-read: 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 Outlook MCP Server. Nothing to install.

What risk level is mark-as-read? +

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

Can I rate-limit mark-as-read? +

Yes. Add a rate_limit block to the mark-as-read 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 mark-as-read completely? +

Set action: deny in the PolicyLayer policy for mark-as-read. 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 mark-as-read? +

mark-as-read is provided by the Outlook MCP Server MCP server (peacockery-studio/outlook-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.