Plugin Builder

What it does

When your agent uses it

• Scaffolding a plugin
• Choosing what to contribute
• Reviewing a manifest
• Debugging a permission

Example prompts

• “/plugin-builder”

What it can do on your machine

Read from SKILL.md and the folder at commit c253cae. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are jsonc and typescript).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  Hosts in commands or code, which the agent is likely to contact:

  • bilibili.com

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Plugin Builder loads about 2.4k tokens when it runs, and up to ~16k if it reads all its reference files. Until then it costs about 229 tokens; SKILL.md has 876 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~229

When it runs · the whole SKILL.md, loaded when a task matches

~2.4k

With references · SKILL.md plus every file in references/, read only if the agent opens them

~16k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from AIDotNet/NextCoWork at commit c253cae, republished under its Apache-2.0 licence (© AIDotNet). 876 words, ~2,399 tokens.

name

plugin-builder

description

Author, package, and debug NextCoWork plugins — the single entry point. Covers the manifest (package.json) and the permission model with per-call capability gates, every contribution point (commands, menus, keybindings, custom editors, views, web apps, agent tools, card views, configuration, bundled Skills) including which install cleanly but do nothing yet, the ncw:doc document channel, result / live-progress / interactive cards, the nextcowork runtime API namespaces, the sandbox and isolation model, and build + ZIP + market publishing rules. Use for scaffolding a plugin, choosing what to contribute, writing or reviewing a manifest, picking or debugging a permission, taking over a file type, bundling Skills with a plugin, giving the agent new tools, or fixing a plugin that builds, installs, activates, renders, or publishes wrong. Detailed material lives in references/ next to this file.

<publisher>.<name>/
├── package.json            # the manifest (required)
├── dist/
│   ├── extension.js        # single-file ESM entry (manifest.main)
│   ├── views/*.html        # view / cardView HTML (optional)
│   └── ...
├── l10n/                   # zh-CN.json + en-US.json (required if you use %keys%)
└── icon.png                # optional (≤256 KB)

{
  "publisher": "ncw", "name": "bilibili", "kind": "webapp",
  "displayName": "哔哩哔哩", "description": "…", "version": "0.1.0",
  "engines": { "nextcowork": "^0.3.0" }, "l10n": "./l10n",
  "permissions": [],
  "hostPermissions": ["https://www.bilibili.com/*"],
  "contributes": { "webApps": [
    { "id": "home", "title": "%app.home%", "icon": "tv", "url": "https://www.bilibili.com/" }
  ] }
}

{
  "publisher": "acme", "name": "hello", "displayName": "Hello", "description": "demo",
  "version": "0.1.0", "engines": { "nextcowork": "^0.3.0" }, "main": "./dist/extension.js",
  "l10n": "./l10n", "activationEvents": ["onTool:say_hello"],
  "permissions": [],
  "contributes": { "tools": [{ "name": "say_hello", "title": "%tool.hello%", "shape": "orchestration" }] }
}

import * as ncw from 'nextcowork'
export function activate(context) {
  context.subscriptions.push(
    ncw.tools.registerTool('say_hello', {
      description: 'Greet someone.',
      inputSchema: { type: 'object', properties: { name: { type: 'string' } }, required: ['name'] },
      readOnly: true, destructive: false, needsNetwork: false,
      async invoke({ input }) {
        return { content: [{ text: `Hello, ${input.name}!` }] }
      }
    })
  )
}

© AIDotNet, Apache-2.0. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 7 other files (references) in resources/skills/plugin-builder of AIDotNet/NextCoWork.

• SKILL.md
• references/agent-tools.md
• references/contribution-points.md
• references/custom-editors.md
• references/manifest-permissions.md
• references/packaging.md
• references/permission-map.md
• references/runtime-api.md

Open the folder on GitHubat commit c253cae