# add_subscriber

Add subscriber to ConvertKit

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

## Facts

- Tool: `add_subscriber`
- 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": "add_subscriber",
    "arguments": {}
  }
}
```

## Why add_subscriber is rated Medium

This tool creates a new subscriber record, which is a reversible write operation. It modifies data (adds an entry) but doesn't delete or overwrite existing data irreversibly, nor does it execute arbitrary code or move money.

From the tool's own definition: "Tool name 'add_subscriber' and description 'Add subscriber to ConvertKit' indicate creation of a new record in an external service (ConvertKit email/marketing platform)."

## Use case

AI agents use add_subscriber 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": {
    "add_subscriber": {
      "limits": [
        {
          "counter": "add_subscriber_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
