set_streaming_source · Unreal MCP: Risk & Policy

WHAT IT DOES

What set_streaming_source does on Unreal

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

WHY IT NEEDS A POLICY

Why set_streaming_source needs a policy

This tool modifies actor component properties related to World Partition streaming configuration. While it changes engine state, it does not execute arbitrary code, delete data irreversibly, or trigger financial transactions. The modification is reversible (configuration can be reconfigured), placing it in the Write category.

From the tool's definition Tool name 'set_streaming_source' and description 'Configure a streaming source component on an actor for World Partition' indicate modification of actor component configuration. The verb 'set' and 'configure' denote state changes to game world objects.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_streaming_source Rate-limited

set_streaming_source 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": {
    "set_streaming_source": {
      "limits": [
        {
          "counter": "set_streaming_source_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 Unreal, so you can run agents against it safely.

FAQ

Questions about set_streaming_source

What does the set_streaming_source tool do? +

Configure a streaming source component on an actor for World Partition. It is categorised as a Write tool in the Unreal MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on set_streaming_source? +

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

What risk level is set_streaming_source? +

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

Can I rate-limit set_streaming_source? +

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

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

set_streaming_source is provided by the Unreal MCP server (sam-david/unreal-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.