update_mailbox_webhook · Run402 MCP: Risk & Policy

WHAT IT DOES

What update_mailbox_webhook does on Run402

AI agents use update_mailbox_webhook to create or update resources in Run402 — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Run402 environment.

WHY IT NEEDS A POLICY

Why update_mailbox_webhook needs a policy

This tool modifies webhook settings, which is a reversible write operation. While webhook updates can have side effects (triggering notifications, routing events), the operation itself is not destructive and doesn't execute arbitrary code or move money. Severity is medium because misconfiguration could route sensitive data to attacker-controlled endpoints, but the core operation is a configuration update.

From the tool's definition Tool name 'update_mailbox_webhook' and description 'Update a webhook' indicate modification of webhook configuration.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_mailbox_webhook Rate-limited

update_mailbox_webhook 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": {
    "update_mailbox_webhook": {
      "limits": [
        {
          "counter": "update_mailbox_webhook_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

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Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Run402, so you can run agents against it safely.

FAQ

Questions about update_mailbox_webhook

What does the update_mailbox_webhook tool do? +

Update a webhook. It is categorised as a Write tool in the Run402 MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on update_mailbox_webhook? +

Register the Run402 MCP server in PolicyLayer and add a rule for update_mailbox_webhook: 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 Run402. Nothing to install.

What risk level is update_mailbox_webhook? +

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

Can I rate-limit update_mailbox_webhook? +

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

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

update_mailbox_webhook is provided by the Run402 MCP server (kychee-com/run402). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.