install_plugin · HC3 MCP Server MCP: Risk & Policy

WHAT IT DOES

What install_plugin does on HC3 MCP Server

AI agents invoke install_plugin to trigger actions in HC3 MCP Server. 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 install_plugin needs a policy

Installing a plugin executes an installation process on the HC3 system, which involves deploying and activating new software/code on the device. This is an Execute-category action as it triggers an external operation (plugin installation) whose effects depend on which plugin is specified.

From the tool's definition Install a plugin by type (mainly for HC2 compatibility)

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

install_plugin Rate-limited

install_plugin 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": {
    "install_plugin": {
      "limits": [
        {
          "counter": "install_plugin_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 HC3 MCP Server, so you can run agents against it safely.

FAQ

Questions about install_plugin

What does the install_plugin tool do? +

Install a plugin by type (mainly for HC2 compatibility). It is categorised as a Execute tool in the HC3 MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on install_plugin? +

Register the HC3 MCP Server MCP server in PolicyLayer and add a rule for install_plugin: 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 HC3 MCP Server. Nothing to install.

What risk level is install_plugin? +

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

Can I rate-limit install_plugin? +

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

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

install_plugin is provided by the HC3 MCP Server MCP server (jangabrielsson/hc3_mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.