functions_rebuild · Run402 MCP: Risk & Policy

WHAT IT DOES

What functions_rebuild does on Run402

AI agents invoke functions_rebuild to trigger actions in Run402. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why functions_rebuild needs a policy

Rebuilding/refreshing functions onto a platform constitutes executing an external operation (redeployment), which can affect running services. It is not purely a write (data modification) nor destructive (not deleting), but it does trigger an active platform-side process whose effects depend on the current function definitions.

From the tool's definition 'Refresh function(s) onto the platform' — triggers a rebuild/redeployment operation of functions on the infrastructure platform

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

functions_rebuild Rate-limited

functions_rebuild stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "functions_rebuild": {
      "limits": [
        {
          "counter": "functions_rebuild_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

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 functions_rebuild

What does the functions_rebuild tool do? +

Refresh function(s) onto the platform. It is categorised as a Execute tool in the Run402 MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on functions_rebuild? +

Register the Run402 MCP server in PolicyLayer and add a rule for functions_rebuild: 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 functions_rebuild? +

functions_rebuild is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit functions_rebuild? +

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

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

functions_rebuild 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.