# start_container

Start a Docker container

Agent View of the PolicyLayer registry record for `start_container`. HTML page: https://policylayer.com/tools/docker/start-container

## Facts

- Tool: `start_container`
- Server: Docker (`@ckreiling/mcp-server-docker`) — https://policylayer.com/tools/docker.md
- Install: `npx -y @ckreiling/mcp-server-docker`
- Homepage: https://github.com/ckreiling/mcp-server-docker
- Risk category: Execute (High risk)
- Registry record: grade F, identity verified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Rate-limited

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "start_container",
    "arguments": {}
  }
}
```

## Why start_container is rated High

Starting a container triggers execution of arbitrary code/applications defined in the container image. The effects are not predetermined and depend on what runs inside the container (databases, services, scripts, etc.). This is Execute rather than Write because it activates running processes with potentially significant external side effects.

From the tool's own definition: "Tool name 'start_container' and description 'Start a Docker container' indicate execution of a containerized process whose behavior and side effects depend entirely on the container's configuration and entrypoint."

## Use case

AI agents invoke start_container to trigger actions in Docker. 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.

## Recommended policy (PolicyLayer)

Verdict: **Rate-limited**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Docker:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "start_container": {
      "limits": [
        {
          "counter": "start_container_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on Docker (18)

- `recreate_container` — Destructive — https://policylayer.com/tools/docker/recreate-container.md
- `remove_container` — Destructive — https://policylayer.com/tools/docker/remove-container.md
- `remove_image` — Destructive — https://policylayer.com/tools/docker/remove-image.md
- `remove_network` — Destructive — https://policylayer.com/tools/docker/remove-network.md
- `remove_volume` — Destructive — https://policylayer.com/tools/docker/remove-volume.md
- `build_image` — Execute — https://policylayer.com/tools/docker/build-image.md
- `create_container` — Execute — https://policylayer.com/tools/docker/create-container.md
- `pull_image` — Execute — https://policylayer.com/tools/docker/pull-image.md
- `run_container` — Execute — https://policylayer.com/tools/docker/run-container.md
- `stop_container` — Execute — https://policylayer.com/tools/docker/stop-container.md
- `fetch_container_logs` — Read — https://policylayer.com/tools/docker/fetch-container-logs.md
- `list_containers` — Read — https://policylayer.com/tools/docker/list-containers.md
- `list_images` — Read — https://policylayer.com/tools/docker/list-images.md
- `list_networks` — Read — https://policylayer.com/tools/docker/list-networks.md
- `list_volumes` — Read — https://policylayer.com/tools/docker/list-volumes.md
- `create_network` — Write — https://policylayer.com/tools/docker/create-network.md
- `create_volume` — Write — https://policylayer.com/tools/docker/create-volume.md
- `push_image` — Write — https://policylayer.com/tools/docker/push-image.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=docker · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/docker