High Risk →

ultimate_start_stream

Start a data stream (U64 only: video, audio, debug)

How to control ultimate_start_stream ↓

What ultimate_start_stream does on Commodore 64 Ultimate MCP Server

AI agents invoke ultimate_start_stream to trigger actions in Commodore 64 Ultimate 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.

High Risk

Why ultimate_start_stream needs a policy

This tool triggers execution of a streaming operation on Commodore 64 Ultimate hardware via REST API. While streaming itself is not destructive or financial, it executes a command that initiates an ongoing external process. The severity is medium rather than high because streaming operations are generally reversible (can be stopped) and have limited blast radius compared to code execution or system modifications.

From the tool's definition Tool name 'ultimate_start_stream' combined with description indicating it 'Start[s] a data stream' of video, audio, or debug output. The action initiates an external operation (streaming) whose effects depend on stream type arguments.

Documented attack patterns abuse exactly the kind of access ultimate_start_stream gives an agent:

How to control ultimate_start_stream

PolicyLayer is an MCP gateway — it sits between your AI agents and Commodore 64 Ultimate MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for ultimate_start_stream:

policy.json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "ultimate_start_stream": {
      "limits": [
        {
          "counter": "ultimate_start_stream_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

ultimate_start_stream 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.

  1. Create a free account and register Commodore 64 Ultimate MCP Server — nothing to install.
  2. Add this policy — paste it, or build it visually.
  3. Point your MCP client (Claude, Cursor, anything) at your gateway URL.
RATE-LIMIT THIS TOOL →

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Related tools and policies

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Questions about ultimate_start_stream

What does the ultimate_start_stream tool do? +

Start a data stream (U64 only: video, audio, debug). It is categorised as a Execute tool in the Commodore 64 Ultimate 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 ultimate_start_stream? +

Register the Commodore 64 Ultimate MCP Server MCP server in PolicyLayer and add a rule for ultimate_start_stream: 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 Commodore 64 Ultimate MCP Server. Nothing to install.

What risk level is ultimate_start_stream? +

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

Can I rate-limit ultimate_start_stream? +

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

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

ultimate_start_stream is provided by the Commodore 64 Ultimate MCP Server MCP server (martijn-devrev/ultimate64mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Commodore 64 Ultimate MCP Server tool call.

Start from Commodore 64 Ultimate MCP Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

Free to start. No card required.

39 Commodore 64 Ultimate MCP Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.

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