add_input_action · Unity MCP: Risk & Policy

WHAT IT DOES

What add_input_action does on Unity

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

WHY IT NEEDS A POLICY

Why add_input_action needs a policy

An AI agent can call add_input_action faster than any human can review — one bad instruction and it creates or modifies resources in Unity by the hundred, each call as confident as the last.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

add_input_action Rate-limited

add_input_action 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": {
    "add_input_action": {
      "limits": [
        {
          "counter": "add_input_action_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 Unity, so you can run agents against it safely.

FAQ

Questions about add_input_action

What does the add_input_action tool do? +

Add a new Action to an Action Map. It is categorised as a Write tool in the Unity MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on add_input_action? +

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

What risk level is add_input_action? +

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

Can I rate-limit add_input_action? +

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

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

add_input_action is provided by the Unity MCP server (@akiojin/unity-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.