About three.ws Assistant Widget
three.ws Assistant Widget is an MCP server that generates paste-ready embeds for floating 3D avatar chatbots on websites. It is for AI assistants or developers configuring the widget, with offline, deterministic generation and validation of settings.
Key features
- 01Generate an embed tag, frame URL, or JavaScript snippet
- 02Configure avatar, background, mode, and appearance
- 03List built-in widget options and attributes
- 04Validate and normalize configuration values
- 05Build embeds without network access
Use cases
- 01Adding a floating avatar chatbot to a website
- 02Generating a standalone frame URL for embedding
- 03Checking available avatars and interaction settings
MCP support
Exposes `build_assistant_widget` and `list_assistant_options` to MCP clients. The tools generate widget embed code and enumerate supported options.
Configuration
Local server config is the same for every client. Copy it into your client’s MCP config file.
npx -y @three-ws/assistant-mcpTHREE_WS_BASEOrigin used in the generated embed URLs (script src, frame URL, builder link). Override only when targeting a preview or self-hosted three.ws deployment.Local servers need a runtime on your machine (e.g. Node.js 18+). Config file locations differ by client; see your client’s docs.
Tools
2Saved tool list · updated 2w ago
| Parameter | Type | Required | Description |
|---|---|---|---|
| mode | enum | No | Interaction mode: "chat" (text only), "speak" (voice only), or "both" (default).chat | speak | both |
| name | string | No | Display name for the assistant / widget header. |
| agent | string | No | A three.ws agent id to drive the assistant, as an alternative to picking an avatar directly. |
| badge | boolean | No | Show the small "three.ws" attribution badge. Defaults to on. |
| voice | boolean | No | Start with voice on (true) or off (false). Defaults to on. |
| accent | string | No | Accent "#hex" color for the widget UI. Default "#f97316". Non-hex values fall back to the default. |
| avatar | string | No | Which avatar to show: a three.ws avatar id, a "/avatars/*.glb" path (e.g. "/avatars/selfie-girl.glb"), or a full GLB URL. Omit for the default mannequin. |
| context | string | No | What the assistant should know about the site (used as its grounding context in chat). |
| greeting | string | No | Opening line the assistant shows on load. |
| position | enum | No | Which corner the launcher sits in: "right" (default) or "left".right | left |
| background | string | No | Backdrop behind the avatar: "transparent" (default), a "#hex" color, a preset (ember, ocean, violet, forest, dusk, slate), or "gradient:#aabbcc,#112233,160". Anything else falls back to transparent. |
Details
From the project README@three-ws/assistant-mcp
Generate a paste-ready three.ws assistant widget, a floating 3D avatar chatbot for any website, from any AI agent.
A Model Context Protocol server that lets any AI assistant build a paste-ready embed for the three.ws assistant widget over stdio. Describe how you want the assistant to look and behave and
build_assistant_widgetreturns a ready-to-paste<script>tag, a standalone frame URL for<iframe>embedding, and an equivalentThreeAssistant.init({...})JavaScript-API snippet, a floating 3D avatar chatbot that lives in the corner of any site.list_assistant_optionsenumerates every built-in avatar, background preset, interaction mode, chat lane, anddata-*attribute you can set.
Both tools are pure and offline: building an embed is deterministic string logic over local validators. Every field is validated and clamped, so a bad or hostile value falls back to a safe default and the generated HTML is always well-formed. No API key, no signer, no payment, no network call. Point THREE_WS_BASE at a deployment (or leave the default) and go.
Install
npm install @three-ws/assistant-mcp
Or run with npx (no install):
npx -y @three-ws/assistant-mcp
Quick start
Claude Code, one line:
claude mcp add assistant -- npx -y @three-ws/assistant-mcp
Claude Desktop / Cursor (claude_desktop_config.json or mcp.json):
{
"mcpServers": {
"assistant": {
"command": "npx",
"args": ["-y", "@three-ws/assistant-mcp"]
}
}
}
Inspect the surface with the MCP Inspector:
npx -y @modelcontextprotocol/inspector npx @three-ws/assistant-mcp
Tools
| Tool | Type | What it does |
|---|---|---|
build_assistant_widget | read-only | A config → a paste-ready <script> embed (non-default settings as data-*), a frame URL, a ThreeAssistant.init() snippet, and the normalized config. |
list_assistant_options | read-only | Enumerate every built-in avatar, background preset and grammar, interaction mode, chat lane, and the full data-* attribute reference. |
build_assistant_widget is a pure function: the same config always yields the same embed, and it never touches the network. The generated <script> tag carries only the settings that differ from their defaults, so a minimal config yields a minimal tag. The frame_url carries every resolved value (including defaults) so the standalone frame renders deterministically when dropped into an <iframe>.
Input parameters
build_assistant_widget, all optional:
| Field | Type / values | Default |
|---|---|---|
avatar | avatar id, /avatars/*.glb path, or GLB URL | mannequin |
agent | a three.ws agent id (alternative to avatar) | (none) |
background | transparent | #hex | ember/ocean/violet/forest/dusk/slate | gradient:#a,#b[,angle] | transparent |
mode | chat | speak | both | both |
name | string (≤ 60) | (none) |
greeting | string (≤ 200) | (none) |
context | string (≤ 500), what the assistant should know about the site | (none) |
accent | #hex | #f97316 |
position | right | left | right |
voice | boolean, start with voice on/off | on |
badge | boolean, show the three.ws attribution badge | on |
Any value that fails validation (a bad hex, an unknown background, an over-long string) falls back to its default rather than being rejected, so you always get a working embed.
list_assistant_options, filter (optional: avatars | backgrounds | modes | chat_lanes | attributes). Omit to get everything.
Example
// build_assistant_widget
> {
"avatar": "/avatars/selfie-girl.glb",
"background": "ocean",
"mode": "both",
"name": "Aria",
"greeting": "Hi! Ask me anything about the site.",
"accent": "#00c2ff",
"position": "left"
}
{
"ok": true,
"snippet": "<script src=\"https://three.ws/assistant/v1.js\" async data-avatar=\"/avatars/selfie-girl.glb\" data-bg=\"ocean\" data-name=\"Aria\" data-greeting=\"Hi! Ask me anything about the site.\" data-accent=\"#00c2ff\" data-position=\"left\"></script>",
"frame_url": "https://three.ws/assistant-frame?avatar=%2Favatars%2Fselfie-girl.glb&bg=ocean&mode=both&name=Aria&greeting=Hi%21+Ask+me+anything+about+the+site.&accent=%2300c2ff",
"js_api": "ThreeAssistant.init({\n \"bg\": \"ocean\",\n \"mode\": \"both\",\n \"accent\": \"#00c2ff\",\n \"position\": \"left\",\n \"avatar\": \"/avatars/selfie-girl.glb\",\n \"name\": \"Aria\",\n \"greeting\": \"Hi! Ask me anything about the site.\"\n});",
"builder_url": "https://three.ws/assistant",
"config": { "bg": "ocean", "mode": "both", "accent": "#00c2ff", "position": "left", "avatar": "/avatars/selfie-girl.glb", "name": "Aria", "greeting": "Hi! Ask me anything about the site." },
"notes": "Chat runs on the free three.ws LLM chain by default (no key). Visitors can paste their own Groq or OpenRouter key in the widget settings for a private lane; that key stays in their browser."
}
Paste the snippet before </body> on any page, or drop the frame_url into an <iframe>. Design it visually first at three.ws/assistant.
Requirements
- Node.js >= 20.
- No network access needed.
THREE_WS_BASEonly sets the origin baked into the generated URLs.
Environment variables
| Variable | Required | Default |
|---|---|---|
THREE_WS_BASE | no | https://three.ws |
Programmatic use
The package entry point exports TOOLS (every tool definition: name, title,
description, inputSchema, annotations, handler) and buildServer(), which returns a
fully-registered McpServer with no transport attached. Both tools are pure and offline, so you
can call them directly as a widget-builder library with no MCP client involved.
// run from a checkout: node this-file.mjs
import { TOOLS, buildServer } from '@three-ws/assistant-mcp';
const build = TOOLS.find((t) => t.name === 'build_assistant_widget');
const { snippet } = await build.handler({ avatar: '/avatars/michelle.glb', background: 'dusk' });
console.log(snippet);
// Or hand the whole registered server to your own MCP transport.
buildServer();
<script src="https://three.ws/assistant/v1.js" async data-avatar="/avatars/michelle.glb" data-bg="dusk"></script>
Links
- Builder: https://three.ws/assistant
- Docs: https://three.ws/docs/assistant-widget
- Homepage: https://three.ws
- Changelog: https://three.ws/changelog
- Issues: https://github.com/nirholas/three.ws/issues
- License: Apache-2.0, see LICENSE
Part of the three.ws SDK suite, 3D AI agents, on-chain identity, and agent payments.
Website · Changelog · GitHub
Comments
New to MCP?
From what the protocol is to installing your first server, these answers cover most first questions.
An open protocol that defines how AI applications connect to external tools and data in a uniform way. Clients talk to the model; MCP servers provide tools, resources and prompt templates. They exchange standard messages, so one server can be reused by many clients.