run_container · Docker MCP Server MCP: Risk & Policy

WHAT IT DOES

What run_container does on Docker MCP Server

AI agents invoke run_container to trigger actions in Docker 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 run_container needs a policy

run_container executes code within a Docker container, which is an external operation whose side effects are entirely dependent on what the image does and what arguments are provided. This is a classic Execute category tool. While Docker containers can theoretically be destructive (if the image deletes data), the primary capability is to execute arbitrary operations.

From the tool's definition Tool description states 'Run an image in a new Docker container', and the tool name is 'run_container'. This executes arbitrary containerized code/operations specified by the image and runtime arguments.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

run_container Rate-limited

run_container 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": {
    "run_container": {
      "limits": [
        {
          "counter": "run_container_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 Docker MCP Server, so you can run agents against it safely.

FAQ

Questions about run_container

What does the run_container tool do? +

Run an image in a new Docker container (preferred over create_container + start_container). It is categorised as a Execute tool in the Docker 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 run_container? +

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

What risk level is run_container? +

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

Can I rate-limit run_container? +

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

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

run_container is provided by the Docker MCP Server MCP server (pnmice/mcp-server-docker). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.