pipeline_pause · Kiln MCP: Risk & Policy

WHAT IT DOES

What pipeline_pause does on Kiln

AI agents invoke pipeline_pause to trigger actions in Kiln. 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 pipeline_pause needs a policy

This tool triggers an external operation on a running 3D printer pipeline, halting execution at the next step boundary. It doesn't read data, write/create data, or delete anything — it controls the execution state of a physical printer process. Misuse could interrupt ongoing prints, potentially wasting materials or causing partial prints, but it is not irreversible (the pipeline can be resumed).

From the tool's definition Pause a running pipeline at the next step boundary

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

pipeline_pause Rate-limited

pipeline_pause 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": {
    "pipeline_pause": {
      "limits": [
        {
          "counter": "pipeline_pause_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 Kiln, so you can run agents against it safely.

FAQ

Questions about pipeline_pause

What does the pipeline_pause tool do? +

Pause a running pipeline at the next step boundary. It is categorised as a Execute tool in the Kiln MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on pipeline_pause? +

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

What risk level is pipeline_pause? +

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

Can I rate-limit pipeline_pause? +

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

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

pipeline_pause is provided by the Kiln MCP server (codeofaxel/Kiln). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.