# mcp_write_file

Write/overwrite entire file in MCP project

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

## Facts

- Tool: `mcp_write_file`
- Server: Claude C2 (`0xyg3n/claude-c2`) — https://policylayer.com/tools/0xyg3n-claude-c2.md
- Homepage: https://github.com/0xyg3n/claude-c2
- Risk category: Write (Medium 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": "mcp_write_file",
    "arguments": {}
  }
}
```

## Why mcp_write_file is rated Medium

This tool creates or modifies files, which is the core definition of Write category. While file overwrite could have significant blast radius (especially in system directories or configuration files), it remains reversible through restoration—distinguishing it from Destructive.

From the tool's own definition: "Tool name explicitly states 'write_file' and description specifies 'Write/overwrite entire file'. The capability to overwrite files represents reversible modification of data."

Risk signals: Bulk/mass operation — affects multiple targets

## Use case

AI agents use mcp_write_file to create or update resources in Claude C2, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Claude C2 environment.

## 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": {
    "mcp_write_file": {
      "limits": [
        {
          "counter": "mcp_write_file_rate",
          "window": "minute",
          "max": 30,
          "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