update_serverless_session · Session Buddy MCP: Risk & Policy

WHAT IT DOES

What update_serverless_session does on Session Buddy

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

WHY IT NEEDS A POLICY

Why update_serverless_session needs a policy

This tool creates or modifies session data and TTL (time-to-live) values reversibly. These are configuration and state changes that can be undone or corrected by subsequent updates. The blast radius is medium because incorrect session updates could affect session continuity or availability, but changes are not destructive (data is not deleted) nor do they execute arbitrary code or involve financial operations.

From the tool's definition Tool name 'update_serverless_session' and description 'Update serverless session data and optionally extend TTL' indicate modification of existing session data and configuration parameters.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_serverless_session Rate-limited

update_serverless_session 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_serverless_session": {
      "limits": [
        {
          "counter": "update_serverless_session_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 Session Buddy, so you can run agents against it safely.

FAQ

Questions about update_serverless_session

What does the update_serverless_session tool do? +

Update serverless session data and optionally extend TTL. It is categorised as a Write tool in the Session Buddy 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_serverless_session? +

Register the Session Buddy MCP server in PolicyLayer and add a rule for update_serverless_session: 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 Session Buddy. Nothing to install.

What risk level is update_serverless_session? +

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

Can I rate-limit update_serverless_session? +

Yes. Add a rate_limit block to the update_serverless_session 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_serverless_session completely? +

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

update_serverless_session is provided by the Session Buddy MCP server (lesleslie/session-buddy). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.