# write_file

Create a new file or completely overwrite an existing file

Agent View of the PolicyLayer registry record for `write_file`. HTML page: https://policylayer.com/tools/io-github-portel-dev-ncp/write-file

## Facts

- Tool: `write_file`
- Server: Ncp (`@portel/ncp`) — https://policylayer.com/tools/io-github-portel-dev-ncp.md
- Install: `npx -y @portel/ncp`
- Homepage: https://github.com/portel-dev/ncp
- 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": "write_file",
    "arguments": {}
  }
}
```

## Why write_file is rated Medium

This tool creates or modifies files, which is a reversible Write operation. However, it can overwrite existing files completely, giving it high severity due to potential data loss and side effects on the system. It does not delete files (which would be Destructive) but the overwrite capability on existing files elevates the risk beyond a simple create operation.

From the tool's own definition: "Tool name 'write_file' and description states 'Create a new file or completely overwrite an existing file'"

## Use case

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

## Recommended policy (PolicyLayer)

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

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "write_file": {
      "limits": [
        {
          "counter": "write_file_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on Ncp (274)

- `backup` — Destructive — https://policylayer.com/tools/io-github-portel-dev-ncp/backup.md
- `bulk_delete` — Destructive — https://policylayer.com/tools/io-github-portel-dev-ncp/bulk-delete.md
- `delete` — Destructive — https://policylayer.com/tools/io-github-portel-dev-ncp/delete.md
- `delete_event` — Destructive — https://policylayer.com/tools/io-github-portel-dev-ncp/delete-event.md
- `delete_key` — Destructive — https://policylayer.com/tools/io-github-portel-dev-ncp/delete-key.md
- `delete_memory` — Destructive — https://policylayer.com/tools/io-github-portel-dev-ncp/delete-memory.md
- `purge_cache` — Destructive — https://policylayer.com/tools/io-github-portel-dev-ncp/purge-cache.md
- `remove` — Destructive — https://policylayer.com/tools/io-github-portel-dev-ncp/remove.md
- `remove_container` — Destructive — https://policylayer.com/tools/io-github-portel-dev-ncp/remove-container.md
- `write_query` — Destructive — https://policylayer.com/tools/io-github-portel-dev-ncp/write-query.md
- `apply` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/apply.md
- `apply_manifest` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/apply-manifest.md
- `build_image` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/build-image.md
- `build_job` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/build-job.md
- `bulk_operations` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/bulk-operations.md
- `click_element` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/click-element.md
- `clone` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/clone.md
- `connect` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/connect.md
- `consume` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/consume.md
- `create_completion` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/create-completion.md
- `create_context` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/create-context.md
- `create_image` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/create-image.md
- `create_prediction` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/create-prediction.md
- `create_video` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/create-video.md
- `deploy` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/deploy.md
- `deploy_project` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/deploy-project.md
- `deploy_server` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/deploy-server.md
- `deploy_site` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/deploy-site.md
- `exec` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/exec.md
- `exec_async` — Execute — https://policylayer.com/tools/io-github-portel-dev-ncp/exec-async.md
- …and 244 more: https://policylayer.com/tools/io-github-portel-dev-ncp.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=io-github-portel-dev-ncp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/io-github-portel-dev-ncp