# shell

Execute shell command on remote client (cmd.exe on Windows, /bin/sh on Linux). If only one client connected, client_id is auto-selected.

Agent View of the PolicyLayer registry record for `shell`. HTML page: https://policylayer.com/tools/0xyg3n-claude-c2/shell

## Facts

- Tool: `shell`
- Server: Claude C2 (`0xyg3n/claude-c2`) — https://policylayer.com/tools/0xyg3n-claude-c2.md
- Homepage: https://github.com/0xyg3n/claude-c2
- Risk category: Execute (High risk)
- Registry record: grade F, identity unverified
- 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": "shell",
    "arguments": {}
  }
}
```

## Why shell is rated High

This tool allows arbitrary shell command execution on remote systems with minimal constraints. Shell commands can read, write, delete files, exfiltrate data, install malware, pivot to other systems, and cause widespread damage depending on the client's privilege level. The blast radius is unlimited (depends entirely on what shell commands an AI agent chooses to run).

From the tool's own definition: "Tool description explicitly states 'Execute shell command on remote client (cmd.exe on Windows, /bin/sh on Linux)'. The term 'Execute' combined with unrestricted shell command capability on remote systems represents the highest-impact execution vector."

## Use case

AI agents invoke shell to trigger actions in Claude C2. 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 Claude C2:

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

## Other tools on Claude C2 (93)

- `kill` — Destructive — https://policylayer.com/tools/0xyg3n-claude-c2/kill.md
- `mv` — Destructive — https://policylayer.com/tools/0xyg3n-claude-c2/mv.md
- `persist_remove` — Destructive — https://policylayer.com/tools/0xyg3n-claude-c2/persist-remove.md
- `reg_delete` — Destructive — https://policylayer.com/tools/0xyg3n-claude-c2/reg-delete.md
- `rm` — Destructive — https://policylayer.com/tools/0xyg3n-claude-c2/rm.md
- `timestomp` — Destructive — https://policylayer.com/tools/0xyg3n-claude-c2/timestomp.md
- `amsi_bypass` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/amsi-bypass.md
- `bypassuac` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/bypassuac.md
- `defender_exclude` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/defender-exclude.md
- `etw_patch` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/etw-patch.md
- `execute_assembly` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/execute-assembly.md
- `firewall_rule` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/firewall-rule.md
- `generate_payload` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/generate-payload.md
- `get_payload` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/get-payload.md
- `getsystem` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/getsystem.md
- `inject` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/inject.md
- `keylog_start` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/keylog-start.md
- `keylog_stop` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/keylog-stop.md
- `mcp_add_tool` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/mcp-add-tool.md
- `mcp_append_code` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/mcp-append-code.md
- `mcp_restart` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/mcp-restart.md
- `mimikatz` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/mimikatz.md
- `persist_registry` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/persist-registry.md
- `persist_schtask` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/persist-schtask.md
- `persist_service` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/persist-service.md
- `persist_startup` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/persist-startup.md
- `persist_wmi` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/persist-wmi.md
- `portscan` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/portscan.md
- `powershell` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/powershell.md
- `privesc_check` — Execute — https://policylayer.com/tools/0xyg3n-claude-c2/privesc-check.md
- …and 63 more: https://policylayer.com/tools/0xyg3n-claude-c2.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=0xyg3n-claude-c2 · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/0xyg3n-claude-c2