juno_functions_upgrade · Junobuild MCP: Risk & Policy

WHAT IT DOES

What juno_functions_upgrade does on Junobuild

AI agents invoke juno_functions_upgrade to trigger actions in Junobuild. 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 juno_functions_upgrade needs a policy

Upgrading a satellite involves deploying new code or configuration to a live system, which is an external operation with significant impact. It goes beyond a simple write (it replaces running software), but may not be strictly irreversible if rollback is possible. The blast radius is high since a botched upgrade could break a production satellite.

From the tool's definition 'Upgrade your satellite' — triggers an upgrade operation on a deployed satellite

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

juno_functions_upgrade Rate-limited

juno_functions_upgrade 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": {
    "juno_functions_upgrade": {
      "limits": [
        {
          "counter": "juno_functions_upgrade_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 Junobuild, so you can run agents against it safely.

FAQ

Questions about juno_functions_upgrade

What does the juno_functions_upgrade tool do? +

Upgrade your satellite. It is categorised as a Execute tool in the Junobuild MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on juno_functions_upgrade? +

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

What risk level is juno_functions_upgrade? +

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

Can I rate-limit juno_functions_upgrade? +

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

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

juno_functions_upgrade is provided by the Junobuild MCP server (junobuild-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.