From 11917c70c4370d56054b879ed80f0a90e8884c33 Mon Sep 17 00:00:00 2001
From: braginini <bangvalo@gmail.com>
Date: Fri, 13 Mar 2026 17:40:57 +0100
Subject: [PATCH] Init

---
 .gitignore                         |   4 +
 README.md                          | 402 +++++++++++++++++++++++++++++
 package-lock.json                  | 113 ++++++++
 package.json                       |  45 ++++
 src/client/AIAssistantProvider.tsx | 288 +++++++++++++++++++++
 src/client/AIChatBot.tsx           | 309 ++++++++++++++++++++++
 src/client/AIFloatingButton.tsx    |  34 +++
 src/client/index.ts                |   4 +
 src/client/styles.ts               | 353 +++++++++++++++++++++++++
 src/server/handler.ts              | 158 ++++++++++++
 src/server/index.ts                |   5 +
 src/server/providers/anthropic.ts  |  53 ++++
 src/server/providers/openai.ts     |  55 ++++
 src/server/providers/types.ts      |  10 +
 src/types.ts                       |  11 +
 tsconfig.json                      |  22 ++
 16 files changed, 1866 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 README.md
 create mode 100644 package-lock.json
 create mode 100644 package.json
 create mode 100644 src/client/AIAssistantProvider.tsx
 create mode 100644 src/client/AIChatBot.tsx
 create mode 100644 src/client/AIFloatingButton.tsx
 create mode 100644 src/client/index.ts
 create mode 100644 src/client/styles.ts
 create mode 100644 src/server/handler.ts
 create mode 100644 src/server/index.ts
 create mode 100644 src/server/providers/anthropic.ts
 create mode 100644 src/server/providers/openai.ts
 create mode 100644 src/server/providers/types.ts
 create mode 100644 src/types.ts
 create mode 100644 tsconfig.json

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..53400d7
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+node_modules/
+dist/
+*.tsbuildinfo
+.idea/
\ No newline at end of file
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..6790892
--- /dev/null
+++ b/README.md
@@ -0,0 +1,402 @@
+# netbird-explain
+
+AI-powered "Explain" assistant for React apps. Users click on UI elements and get contextual AI explanations via a chat panel.
+
+The package has two entry points:
+
+- `netbird-explain/client` — React components (provider, chat panel, floating button)
+- `netbird-explain/server` — Node.js handler that proxies requests to Anthropic or OpenAI
+
+No CSS framework required — the package is fully self-contained with inline styles and CSS custom properties.
+
+## Installation
+
+```bash
+npm install netbird-explain
+```
+
+Peer dependencies: `react >=18`, `react-dom >=18`.
+
+For local development as a workspace package, add it to your `package.json`:
+
+```json
+{
+  "dependencies": {
+    "netbird-explain": "file:./packages/netbird-explain"
+  }
+}
+```
+
+If you're using Next.js, add to `next.config.js`:
+
+```js
+module.exports = {
+  transpilePackages: ["netbird-explain"],
+};
+```
+
+---
+
+## Client
+
+### Setup
+
+Wrap your app with `AIAssistantProvider`:
+
+```tsx
+import { AIAssistantProvider } from "netbird-explain/client";
+
+export default function App({ children }) {
+  return (
+    <AIAssistantProvider
+      endpoint="http://localhost:3080/api/ai/chat"
+      apiKey="your-api-key"
+    >
+      {children}
+    </AIAssistantProvider>
+  );
+}
+```
+
+This renders the floating action button and chat panel automatically. No CSS imports are needed — the provider injects all required styles via CSS custom properties.
+
+### Props
+
+| Prop       | Type        | Required | Description                         |
+| ---------- | ----------- | -------- | ----------------------------------- |
+| `endpoint` | `string`    | Yes      | URL of the AI chat API              |
+| `apiKey`   | `string`    | No       | Bearer token sent with each request |
+| `children` | `ReactNode` | Yes      | Your application                    |
+
+### Marking elements as explainable
+
+Add the `data-nb-explain` attribute to any element you want users to be able to click on in explain mode:
+
+```tsx
+<div data-nb-explain>
+  <Label>Name</Label>
+  <Input value={name} onChange={setName} />
+</div>
+```
+
+When clicked, the library extracts a label from the element (first `<label>`, heading, or text content) and sends it as the query.
+
+You can also pass a custom label directly:
+
+```tsx
+<div data-nb-explain="Database connection string">...</div>
+```
+
+### Documentation URLs
+
+Attach docs to an element or its parent so the AI can reference them:
+
+```tsx
+<div data-nb-explain-docs='["https://docs.example.com/resources"]'>
+  <div data-nb-explain>...</div>
+</div>
+```
+
+### Excluding elements
+
+Use `data-nb-explain-ignore` to prevent an element from being selectable in explain mode:
+
+```tsx
+<button data-nb-explain-ignore onClick={enterExplainMode}>
+  Explain
+</button>
+```
+
+### Setting page/modal context
+
+Use the `useAIAssistant` hook to provide context that gets included in every query:
+
+```tsx
+import { useAIAssistant } from "netbird-explain/client";
+
+function MyModal() {
+  const { setExplainContext, clearExplainContext } = useAIAssistant();
+
+  useEffect(() => {
+    setExplainContext({
+      modalName: "Add Resource",
+      pageName: "Networks",
+      docsUrls: ["https://docs.example.com/networks"],
+    });
+    return () => clearExplainContext();
+  }, []);
+
+  return <div data-nb-explain>...</div>;
+}
+```
+
+This produces queries like: `Explain "Name" on Add Resource modal in Networks`.
+
+### Hook API
+
+`useAIAssistant()` returns:
+
+| Method / Property        | Description                                |
+| ------------------------ | ------------------------------------------ |
+| `openChat(query?)`       | Open the chat panel, optionally with a query |
+| `closeChat()`            | Close the chat panel                       |
+| `isChatOpen`             | Whether the chat panel is open             |
+| `explainMode`            | Whether explain mode is active             |
+| `enterExplainMode()`     | Activate explain mode (click-to-explain)   |
+| `exitExplainMode()`      | Deactivate explain mode                    |
+| `setExplainContext(ctx)` | Set page/modal context for queries         |
+| `clearExplainContext()`  | Clear the context                          |
+
+### Theming
+
+The package ships with a dark theme out of the box. All visual properties are controlled via CSS custom properties (`--nb-explain-*`) injected into `:root` by the provider. Override any of them in your own CSS to match your app's look and feel.
+
+#### How it works
+
+1. `AIAssistantProvider` injects a `<style>` tag with default values for all `--nb-explain-*` variables.
+2. Components use inline styles that reference these variables (e.g., `background: var(--nb-explain-bg)`).
+3. Your CSS can override any variable — later declarations on `:root` or more specific selectors win.
+
+#### Overriding in CSS
+
+Add a stylesheet or `<style>` block **after** the provider mounts (or use higher specificity):
+
+```css
+:root {
+  /* Change to a light theme */
+  --nb-explain-bg: #ffffff;
+  --nb-explain-bg-subtle: rgba(0, 0, 0, 0.04);
+  --nb-explain-bg-hover: rgba(0, 0, 0, 0.06);
+  --nb-explain-border: rgba(0, 0, 0, 0.12);
+  --nb-explain-text: #1a1a1a;
+  --nb-explain-text-muted: #6b7280;
+  --nb-explain-text-dim: #9ca3af;
+  --nb-explain-accent: #2563eb;
+  --nb-explain-accent-hover: #3b82f6;
+  --nb-explain-user-bg: #2563eb;
+  --nb-explain-user-text: #ffffff;
+}
+```
+
+#### Full variable reference
+
+| Variable              | Default                          | Description                        |
+| --------------------- | -------------------------------- | ---------------------------------- |
+| `--nb-explain-bg`             | `#0a0a0f`                        | Chat panel background              |
+| `--nb-explain-bg-subtle`      | `rgba(255,255,255,0.06)`         | Input field & assistant message bg |
+| `--nb-explain-bg-hover`       | `rgba(255,255,255,0.08)`         | Hover state background             |
+| `--nb-explain-border`         | `rgba(255,255,255,0.1)`          | Border color                       |
+| `--nb-explain-text`           | `#f0f0f5`                        | Primary text color                 |
+| `--nb-explain-text-muted`     | `#9ca3af`                        | Secondary text color               |
+| `--nb-explain-text-dim`       | `#6b7280`                        | Placeholder / tertiary text        |
+| `--nb-explain-accent`         | `#eab308`                        | Accent color (buttons, icons)      |
+| `--nb-explain-accent-hover`   | `#facc15`                        | Accent hover state                 |
+| `--nb-explain-accent-glow`    | `rgba(234,179,8,0.15)`           | Accent glow (avatar backgrounds)   |
+| `--nb-explain-user-bg`        | `#4f46e5`                        | User message bubble background     |
+| `--nb-explain-user-text`      | `#ffffff`                        | User message text color            |
+| `--nb-explain-user-glow`      | `rgba(79,70,229,0.25)`           | User avatar glow                   |
+| `--nb-explain-radius`         | `12px`                           | Panel border radius                |
+| `--nb-explain-radius-sm`      | `8px`                            | Message bubble border radius       |
+| `--nb-explain-radius-xs`      | `6px`                            | Button border radius               |
+| `--nb-explain-font`           | system font stack                | Font family for all components     |
+| `--nb-explain-shadow`         | large drop shadow                | Chat panel box shadow              |
+| `--nb-explain-banner-bg`      | `rgba(234,179,8,0.92)`           | Explain mode banner background     |
+| `--nb-explain-banner-text`    | `#000000`                        | Explain mode banner text           |
+| `--nb-explain-error-text`     | `#f87171`                        | Error message text                 |
+
+### Data attributes
+
+| Attribute            | Description                                                        |
+| -------------------- | ------------------------------------------------------------------ |
+| `data-nb-explain`       | Marks element as explainable. Value can be a custom label or boolean. |
+| `data-nb-explain-docs`  | JSON array of documentation URLs for context.                      |
+| `data-nb-explain-ignore` | Element is non-interactive during explain mode.                   |
+
+---
+
+## Server
+
+The server module provides a framework-agnostic handler that proxies chat requests to Anthropic or OpenAI.
+
+### With Express
+
+```ts
+import express from "express";
+import { createAssistant } from "netbird-explain/server";
+
+const assistant = createAssistant({
+  provider: "anthropic",
+  apiKey: process.env.ANTHROPIC_API_KEY!,
+  model: "claude-sonnet-4-20250514",
+  systemPrompt: "You are a helpful assistant for MyApp.",
+});
+
+const app = express();
+app.use(express.json());
+
+app.post("/api/ai/chat", assistant.handler({ apiKey: "your-api-key" }));
+
+app.listen(3080);
+```
+
+### With plain Node.js HTTP
+
+```ts
+import http from "http";
+import { createAssistant } from "netbird-explain/server";
+
+const assistant = createAssistant({
+  provider: "openai",
+  apiKey: process.env.OPENAI_API_KEY!,
+  model: "gpt-4o",
+});
+
+const handle = assistant.handler({ apiKey: "your-api-key" });
+
+http.createServer(handle).listen(3080);
+```
+
+### Programmatic usage (no HTTP)
+
+```ts
+const assistant = createAssistant({
+  provider: "anthropic",
+  apiKey: process.env.ANTHROPIC_API_KEY!,
+});
+
+const { reply } = await assistant.chat({
+  messages: [{ role: "user", content: "What is a network resource?" }],
+});
+```
+
+### `createAssistant(config)`
+
+| Option         | Type                          | Required | Default                  |
+| -------------- | ----------------------------- | -------- | ------------------------ |
+| `provider`     | `"anthropic"` \| `"openai"`  | Yes      | —                        |
+| `apiKey`       | `string`                      | Yes      | —                        |
+| `model`        | `string`                      | No       | Provider default         |
+| `systemPrompt` | `string`                      | No       | Generic assistant prompt |
+
+### `assistant.handler(opts?)`
+
+Returns a `(req, res) => Promise<void>` handler compatible with Express, plain `http`, and similar frameworks.
+
+| Option   | Type     | Description                                                    |
+| -------- | -------- | -------------------------------------------------------------- |
+| `apiKey` | `string` | If set, requires `Authorization: Bearer <key>` on requests     |
+
+### API contract
+
+**Request** `POST /api/ai/chat`
+
+```json
+{
+  "messages": [
+    { "role": "context", "content": "Docs: https://..." },
+    { "role": "user", "content": "Explain network routes" }
+  ]
+}
+```
+
+**Response**
+
+```json
+{
+  "reply": "Network routes allow you to..."
+}
+```
+
+**Error codes:** `400` (bad request), `401` (unauthorized), `502` (LLM error).
+
+---
+
+## Standalone dev server
+
+The `server/` directory in the dashboard repo contains a ready-to-run Express server for local development.
+
+```bash
+cd server
+cp .env .env.local   # edit with your LLM API key
+npm install
+node index.js
+```
+
+Environment variables:
+
+| Variable            | Default                    | Description            |
+| ------------------- | -------------------------- | ---------------------- |
+| `PORT`              | `3080`                     | Server port            |
+| `API_KEY`           | `nb-ai-dev-key-change-me`  | Bearer token for auth  |
+| `LLM_PROVIDER`      | `anthropic`                | `anthropic` or `openai` |
+| `ANTHROPIC_API_KEY`  | —                          | Anthropic API key      |
+| `ANTHROPIC_MODEL`   | `claude-sonnet-4-20250514` | Model ID               |
+| `OPENAI_API_KEY`     | —                          | OpenAI API key         |
+| `OPENAI_MODEL`      | `gpt-4o`                   | Model ID               |
+| `SYSTEM_PROMPT`     | Generic NetBird prompt      | System prompt for the LLM |
+
+---
+
+## Full integration example
+
+```tsx
+// layout.tsx — wrap app with provider
+import { AIAssistantProvider } from "netbird-explain/client";
+
+export default function Layout({ children }) {
+  return (
+    <AIAssistantProvider
+      endpoint={process.env.NEXT_PUBLIC_AI_SERVER_URL || "http://localhost:3080/api/ai/chat"}
+      apiKey={process.env.NEXT_PUBLIC_AI_API_KEY || "nb-ai-dev-key-change-me"}
+    >
+      {children}
+    </AIAssistantProvider>
+  );
+}
+```
+
+```tsx
+// MyModal.tsx — add explain support to a modal
+import { useAIAssistant } from "netbird-explain/client";
+import { Sparkles } from "lucide-react";
+
+function MyModal() {
+  const { setExplainContext, clearExplainContext, explainMode, enterExplainMode, exitExplainMode } =
+    useAIAssistant();
+
+  useEffect(() => {
+    setExplainContext({
+      modalName: "Add Resource",
+      pageName: "Networks",
+      docsUrls: ["https://docs.netbird.io/manage/networks"],
+    });
+    return () => clearExplainContext();
+  }, []);
+
+  return (
+    <div data-nb-explain>
+      <button
+        data-nb-explain-ignore
+        onClick={() => (explainMode ? exitExplainMode() : enterExplainMode())}
+      >
+        <Sparkles size={13} />
+        {explainMode ? "Click an element..." : "Explain"}
+      </button>
+
+      <div data-nb-explain>
+        <label>Name</label>
+        <input placeholder="e.g., Postgres Database" />
+      </div>
+
+      <div data-nb-explain>
+        <label>Address</label>
+        <input placeholder="e.g., 10.0.0.1" />
+      </div>
+    </div>
+  );
+}
+```
+
+## License
+
+BSD-3-Clause
\ No newline at end of file
diff --git a/package-lock.json b/package-lock.json
new file mode 100644
index 0000000..b7f2ba4
--- /dev/null
+++ b/package-lock.json
@@ -0,0 +1,113 @@
+{
+  "name": "netbird-explain",
+  "version": "0.1.0",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {
+    "": {
+      "name": "netbird-explain",
+      "version": "0.1.0",
+      "license": "BSD-3-Clause",
+      "dependencies": {
+        "lucide-react": ">=0.300.0"
+      },
+      "devDependencies": {
+        "@types/react": "^18.0.0",
+        "@types/react-dom": "^18.0.0",
+        "typescript": "^5.0.0"
+      },
+      "peerDependencies": {
+        "react": ">=18.0.0",
+        "react-dom": ">=18.0.0"
+      }
+    },
+    "node_modules/@types/prop-types": {
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+      "dev": true,
+      "license": "MIT"
+    },
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+      "license": "MIT",
+      "dependencies": {
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+        "csstype": "^3.2.2"
+      }
+    },
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+      "license": "MIT"
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+      "license": "ISC",
+      "peerDependencies": {
+        "react": "^16.5.1 || ^17.0.0 || ^18.0.0 || ^19.0.0"
+      }
+    },
+    "node_modules/react": {
+      "version": "19.2.4",
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+      "peer": true,
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+      "dev": true,
+      "license": "Apache-2.0",
+      "bin": {
+        "tsc": "bin/tsc",
+        "tsserver": "bin/tsserver"
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+      "engines": {
+        "node": ">=14.17"
+      }
+    }
+  }
+}
diff --git a/package.json b/package.json
new file mode 100644
index 0000000..74f6ec5
--- /dev/null
+++ b/package.json
@@ -0,0 +1,45 @@
+{
+  "name": "netbird-explain",
+  "version": "0.1.0",
+  "description": "Full-stack AI assistant library with React frontend components and Node.js backend handler",
+  "license": "BSD-3-Clause",
+  "main": "./dist/client/index.js",
+  "types": "./dist/client/index.d.ts",
+  "exports": {
+    "./client": {
+      "types": "./dist/client/index.d.ts",
+      "default": "./dist/client/index.js"
+    },
+    "./server": {
+      "types": "./dist/server/index.d.ts",
+      "default": "./dist/server/index.js"
+    }
+  },
+  "typesVersions": {
+    "*": {
+      "client": ["./dist/client/index.d.ts"],
+      "server": ["./dist/server/index.d.ts"]
+    }
+  },
+  "files": ["dist", "src"],
+  "scripts": {
+    "build": "tsc",
+    "typecheck": "tsc --noEmit"
+  },
+  "peerDependencies": {
+    "react": ">=18.0.0",
+    "react-dom": ">=18.0.0"
+  },
+  "dependencies": {
+    "lucide-react": ">=0.300.0"
+  },
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/netbirdio/explain.git"
+  },
+  "devDependencies": {
+    "@types/react": "^18.0.0",
+    "@types/react-dom": "^18.0.0",
+    "typescript": "^5.0.0"
+  }
+}
\ No newline at end of file
diff --git a/src/client/AIAssistantProvider.tsx b/src/client/AIAssistantProvider.tsx
new file mode 100644
index 0000000..8b99d28
--- /dev/null
+++ b/src/client/AIAssistantProvider.tsx
@@ -0,0 +1,288 @@
+"use client";
+
+import React, {
+  createContext,
+  useCallback,
+  useContext,
+  useEffect,
+  useState,
+} from "react";
+import type { ExplainContext } from "../types";
+import AIChatBot from "./AIChatBot";
+import AIFloatingButton from "./AIFloatingButton";
+import * as S from "./styles";
+
+type AIAssistantContextType = {
+  openChat: (selectedText?: string) => void;
+  closeChat: () => void;
+  isChatOpen: boolean;
+  explainMode: boolean;
+  enterExplainMode: () => void;
+  exitExplainMode: () => void;
+  setExplainContext: (ctx: ExplainContext) => void;
+  clearExplainContext: () => void;
+};
+
+const AIAssistantContext = createContext<AIAssistantContextType>({
+  openChat: () => {},
+  closeChat: () => {},
+  isChatOpen: false,
+  explainMode: false,
+  enterExplainMode: () => {},
+  exitExplainMode: () => {},
+  setExplainContext: () => {},
+  clearExplainContext: () => {},
+});
+
+export const useAIAssistant = () => useContext(AIAssistantContext);
+
+type AIAssistantProviderProps = {
+  endpoint: string;
+  apiKey?: string;
+  children: React.ReactNode;
+};
+
+/**
+ * Find the closest ancestor (or self) with a data-nb-explain attribute.
+ * Returns null if nothing is explainable.
+ */
+function findExplainable(el: HTMLElement): HTMLElement | null {
+  return el.closest("[data-nb-explain]") as HTMLElement | null;
+}
+
+/**
+ * Extract a short label from an explainable element by looking for
+ * a label, heading, or first bit of text content.
+ */
+function extractLabel(el: HTMLElement): string {
+  const label = el.querySelector("label") as HTMLElement | null;
+  if (label?.innerText?.trim()) return label.innerText.trim();
+
+  const heading = el.querySelector("h1, h2, h3, h4") as HTMLElement | null;
+  if (heading?.innerText?.trim()) return heading.innerText.trim();
+
+  const text = el.innerText?.trim();
+  if (text && text.length <= 80) return text;
+  if (text) return text.slice(0, 80) + "...";
+
+  return "this element";
+}
+
+/**
+ * Look for data-nb-explain-docs on the element or its ancestors.
+ * Returns an array of documentation URLs, or an empty array.
+ */
+function findExplainDocs(el: HTMLElement): string[] {
+  const withDocs = el.closest("[data-nb-explain-docs]") as HTMLElement | null;
+  if (!withDocs) return [];
+
+  const raw = withDocs.getAttribute("data-nb-explain-docs") || "";
+  try {
+    const parsed = JSON.parse(raw);
+    if (Array.isArray(parsed)) return parsed;
+  } catch {
+    // If not valid JSON, treat as a single URL
+    if (raw.trim()) return [raw.trim()];
+  }
+  return [];
+}
+
+function buildQuery(
+  label: string,
+  ctx: ExplainContext | null,
+  elementDocs: string[],
+): string {
+  let userMessage = `Explain "${label}"`;
+  if (ctx) {
+    if (ctx.modalName) userMessage += ` on ${ctx.modalName} modal`;
+    if (ctx.pageName) userMessage += ` in ${ctx.pageName}`;
+  }
+
+  // Merge docs from context and element attribute
+  const allDocs = [
+    ...(ctx?.docsUrls || []),
+    ...elementDocs,
+  ];
+  // Deduplicate
+  const uniqueDocs = [...new Set(allDocs)];
+
+  const parts = [userMessage];
+  if (uniqueDocs.length > 0) {
+    parts.push(`Docs: ${uniqueDocs.join(", ")}`);
+  }
+  return parts.join("\n");
+}
+
+export default function AIAssistantProvider({
+  endpoint,
+  apiKey,
+  children,
+}: AIAssistantProviderProps) {
+  const [isChatOpen, setIsChatOpen] = useState(false);
+  const [initialQuery, setInitialQuery] = useState("");
+  const [explainMode, setExplainMode] = useState(false);
+  const [hoveredEl, setHoveredEl] = useState<HTMLElement | null>(null);
+  const [explainCtx, setExplainCtx] = useState<ExplainContext | null>(null);
+
+  const openChat = useCallback((selectedText?: string) => {
+    setInitialQuery(selectedText || "");
+    setIsChatOpen(true);
+    setExplainMode(false);
+    setHoveredEl(null);
+  }, []);
+
+  const closeChat = useCallback(() => {
+    setIsChatOpen(false);
+    setInitialQuery("");
+  }, []);
+
+  const enterExplainMode = useCallback(() => {
+    setExplainMode(true);
+  }, []);
+
+  const exitExplainMode = useCallback(() => {
+    setExplainMode(false);
+    setHoveredEl(null);
+  }, []);
+
+  const setExplainContext = useCallback((ctx: ExplainContext) => {
+    setExplainCtx(ctx);
+  }, []);
+
+  const clearExplainContext = useCallback(() => {
+    setExplainCtx(null);
+  }, []);
+
+  // Explain mode: highlight explainable elements on hover, open chat on click
+  useEffect(() => {
+    if (!explainMode) return;
+
+    const handleMouseOver = (e: MouseEvent) => {
+      const target = e.target as HTMLElement;
+      if (
+        target.closest("[data-nb-explain-ignore]") ||
+        target.closest("[data-nb-explain-banner]")
+      )
+        return;
+      const explainable = findExplainable(target);
+      setHoveredEl(explainable);
+    };
+
+    const handleMouseOut = () => {
+      setHoveredEl(null);
+    };
+
+    const handleClick = (e: MouseEvent) => {
+      const target = e.target as HTMLElement;
+      if (
+        target.closest("[data-nb-explain-ignore]") ||
+        target.closest("[data-nb-explain-banner]")
+      )
+        return;
+
+      e.preventDefault();
+      e.stopPropagation();
+
+      const explainable = findExplainable(target);
+      if (!explainable) return;
+
+      const attrValue = explainable.getAttribute("data-nb-explain") || "";
+      const label =
+        attrValue && attrValue !== "true"
+          ? attrValue
+          : extractLabel(explainable);
+
+      const elementDocs = findExplainDocs(explainable);
+      const query = buildQuery(label, explainCtx, elementDocs);
+      openChat(query);
+    };
+
+    const handleKeyDown = (e: KeyboardEvent) => {
+      if (e.key === "Escape") {
+        exitExplainMode();
+      }
+    };
+
+    document.addEventListener("mouseover", handleMouseOver, true);
+    document.addEventListener("mouseout", handleMouseOut, true);
+    document.addEventListener("click", handleClick, true);
+    document.addEventListener("keydown", handleKeyDown);
+
+    return () => {
+      document.removeEventListener("mouseover", handleMouseOver, true);
+      document.removeEventListener("mouseout", handleMouseOut, true);
+      document.removeEventListener("click", handleClick, true);
+      document.removeEventListener("keydown", handleKeyDown);
+    };
+  }, [explainMode, explainCtx, openChat, exitExplainMode]);
+
+  // Apply/remove highlight on hovered explainable element via CSS class
+  useEffect(() => {
+    if (!hoveredEl) return;
+    hoveredEl.setAttribute("data-nb-explain-highlight", "");
+    return () => {
+      hoveredEl.removeAttribute("data-nb-explain-highlight");
+    };
+  }, [hoveredEl]);
+
+  // Force-remove all highlights when leaving explain mode
+  useEffect(() => {
+    if (!explainMode) {
+      document.querySelectorAll("[data-nb-explain-highlight]").forEach((el) => {
+        el.removeAttribute("data-nb-explain-highlight");
+      });
+    }
+  }, [explainMode]);
+
+  return (
+    <AIAssistantContext.Provider
+      value={{
+        openChat,
+        closeChat,
+        isChatOpen,
+        explainMode,
+        enterExplainMode,
+        exitExplainMode,
+        setExplainContext,
+        clearExplainContext,
+      }}
+    >
+      {/* Inject CSS custom properties, animations, and highlight styles */}
+      <style>{S.CSS_VARS + S.ANIMATIONS + S.HIGHLIGHT_STYLES}</style>
+
+      {children}
+
+      {/* Explain mode banner */}
+      {explainMode && (
+        <div data-nb-explain-banner style={S.banner}>
+          <span>Click on a highlighted element to explain it</span>
+          <button
+            onClick={() => exitExplainMode()}
+            style={S.bannerCancel}
+          >
+            Cancel
+          </button>
+        </div>
+      )}
+
+      <AIFloatingButton
+        isOpen={isChatOpen}
+        onClick={() => {
+          if (isChatOpen) {
+            closeChat();
+          } else {
+            openChat();
+          }
+        }}
+      />
+
+      <AIChatBot
+        open={isChatOpen}
+        onClose={closeChat}
+        initialQuery={initialQuery}
+        endpoint={endpoint}
+        apiKey={apiKey}
+      />
+    </AIAssistantContext.Provider>
+  );
+}
diff --git a/src/client/AIChatBot.tsx b/src/client/AIChatBot.tsx
new file mode 100644
index 0000000..63b85ab
--- /dev/null
+++ b/src/client/AIChatBot.tsx
@@ -0,0 +1,309 @@
+"use client";
+
+import {
+  Bot,
+  MessageCircleQuestion,
+  Send,
+  Sparkles,
+  User,
+  X,
+} from "lucide-react";
+import React, { useCallback, useEffect, useRef, useState } from "react";
+import type { Message } from "../types";
+import * as S from "./styles";
+
+type Props = {
+  open: boolean;
+  onClose: () => void;
+  initialQuery: string;
+  endpoint: string;
+  apiKey?: string;
+};
+
+async function fetchAIResponse(
+  endpoint: string,
+  apiKey: string | undefined,
+  messages: Message[],
+): Promise<string> {
+  const headers: Record<string, string> = {
+    "Content-Type": "application/json",
+  };
+  if (apiKey) {
+    headers["Authorization"] = `Bearer ${apiKey}`;
+  }
+
+  const response = await fetch(endpoint, {
+    method: "POST",
+    headers,
+    body: JSON.stringify({
+      messages: messages.map((m) => ({
+        role: m.role,
+        content: m.content,
+      })),
+    }),
+  });
+
+  if (!response.ok) {
+    const text = await response.text();
+    throw new Error(`${response.status}: ${text}`);
+  }
+
+  const data = await response.json();
+  return data.reply;
+}
+
+export default function AIChatBot({
+  open,
+  onClose,
+  initialQuery,
+  endpoint,
+  apiKey,
+}: Props) {
+  const [messages, setMessages] = useState<Message[]>([]);
+  const [input, setInput] = useState("");
+  const [isTyping, setIsTyping] = useState(false);
+  const messagesEndRef = useRef<HTMLDivElement>(null);
+  const inputRef = useRef<HTMLInputElement>(null);
+  const hasProcessedInitialQuery = useRef(false);
+
+  const scrollToBottom = useCallback(() => {
+    messagesEndRef.current?.scrollIntoView({ behavior: "smooth" });
+  }, []);
+
+  useEffect(() => {
+    scrollToBottom();
+  }, [messages, isTyping, scrollToBottom]);
+
+  const getAIResponse = useCallback(
+    async (allMessages: Message[]) => {
+      setIsTyping(true);
+      try {
+        const reply = await fetchAIResponse(endpoint, apiKey, allMessages);
+        const response: Message = {
+          id: Date.now().toString(),
+          role: "assistant",
+          content: reply,
+        };
+        setMessages((prev) => [...prev, response]);
+      } catch (err) {
+        const errorMsg =
+          err instanceof Error ? err.message : "Unknown error";
+        const response: Message = {
+          id: Date.now().toString(),
+          role: "assistant",
+          content: `Sorry, I couldn't get a response. Error: ${errorMsg}`,
+        };
+        setMessages((prev) => [...prev, response]);
+      } finally {
+        setIsTyping(false);
+      }
+    },
+    [endpoint, apiKey],
+  );
+
+  // Handle initial query from explain mode
+  useEffect(() => {
+    if (open && initialQuery && !hasProcessedInitialQuery.current) {
+      hasProcessedInitialQuery.current = true;
+
+      const lines = initialQuery.split("\n");
+      const userMessage = lines[0];
+      const docsLine = lines.find((l) => l.startsWith("Docs: "));
+
+      const msgs: Message[] = [];
+
+      if (docsLine) {
+        msgs.push({
+          id: Date.now().toString() + "-ctx",
+          role: "context",
+          content: docsLine,
+        });
+      }
+
+      msgs.push({
+        id: Date.now().toString(),
+        role: "user",
+        content: userMessage,
+      });
+
+      setMessages(msgs);
+      getAIResponse(msgs);
+    }
+  }, [open, initialQuery, getAIResponse]);
+
+  // Reset when closed
+  useEffect(() => {
+    if (!open) {
+      hasProcessedInitialQuery.current = false;
+      setMessages([]);
+      setInput("");
+      setIsTyping(false);
+    }
+  }, [open]);
+
+  // Focus input when opened
+  useEffect(() => {
+    if (open) {
+      setTimeout(() => inputRef.current?.focus(), 200);
+    }
+  }, [open]);
+
+  const sendMessage = useCallback(() => {
+    const text = input.trim();
+    if (!text || isTyping) return;
+
+    const userMsg: Message = {
+      id: Date.now().toString(),
+      role: "user",
+      content: text,
+    };
+    const updatedMessages = [...messages, userMsg];
+    setMessages(updatedMessages);
+    setInput("");
+    getAIResponse(updatedMessages);
+  }, [input, isTyping, messages, getAIResponse]);
+
+  const handleKeyDown = (e: React.KeyboardEvent) => {
+    if (e.key === "Enter" && !e.shiftKey) {
+      e.preventDefault();
+      sendMessage();
+    }
+  };
+
+  if (!open) return null;
+
+  const active = !!input.trim() && !isTyping;
+
+  return (
+    <div style={S.chatPanel}>
+      {/* Header */}
+      <div style={S.chatHeader}>
+        <div style={S.chatHeaderLeft}>
+          <div style={S.chatHeaderIcon}>
+            <Sparkles size={15} style={{ color: "var(--nb-explain-accent)" }} />
+          </div>
+          <div>
+            <h3 style={S.chatHeaderTitle}>AI Assistant</h3>
+            <span style={S.chatHeaderSubtitle}>Ask anything</span>
+          </div>
+        </div>
+        <button
+          onClick={onClose}
+          style={S.chatCloseBtn}
+          onMouseEnter={(e) => {
+            e.currentTarget.style.color = "var(--nb-explain-text)";
+            e.currentTarget.style.background = "var(--nb-explain-bg-hover)";
+          }}
+          onMouseLeave={(e) => {
+            e.currentTarget.style.color = "var(--nb-explain-text-dim)";
+            e.currentTarget.style.background = "none";
+          }}
+        >
+          <X size={16} />
+        </button>
+      </div>
+
+      {/* Messages */}
+      <div style={S.messagesArea}>
+        {messages.length === 0 && !isTyping && (
+          <div style={S.emptyState}>
+            <MessageCircleQuestion
+              size={40}
+              style={{ color: "var(--nb-explain-text-dim)" }}
+            />
+            <div>
+              <p style={S.emptyStateTitle}>How can I help?</p>
+              <p style={S.emptyStateHint}>
+                Use the Explain button to click on any element, or ask a
+                question below.
+              </p>
+            </div>
+          </div>
+        )}
+
+        {messages.map((msg) =>
+          msg.role === "context" ? (
+            <div key={msg.id} style={S.contextBadge}>
+              <div style={S.contextBadgeInner}>
+                <Sparkles
+                  size={10}
+                  style={{ color: "var(--nb-explain-accent)", opacity: 0.6 }}
+                />
+                {msg.content}
+              </div>
+            </div>
+          ) : (
+            <div key={msg.id} style={S.messageRow(msg.role === "user")}>
+              {msg.role === "assistant" && (
+                <div style={S.messageAvatar(false)}>
+                  <Bot size={13} style={{ color: "var(--nb-explain-accent)" }} />
+                </div>
+              )}
+              <div style={S.messageBubble(msg.role === "user")}>
+                {msg.content.split("\n").map((line, i) => (
+                  <React.Fragment key={i}>
+                    {line
+                      .split(/(\*\*[^*]+\*\*)/)
+                      .map((part, j) =>
+                        part.startsWith("**") && part.endsWith("**") ? (
+                          <strong key={j} style={S.messageBold}>
+                            {part.slice(2, -2)}
+                          </strong>
+                        ) : (
+                          <React.Fragment key={j}>{part}</React.Fragment>
+                        ),
+                      )}
+                    {i < msg.content.split("\n").length - 1 && <br />}
+                  </React.Fragment>
+                ))}
+              </div>
+              {msg.role === "user" && (
+                <div style={S.messageAvatar(true)}>
+                  <User size={13} style={{ color: "var(--nb-explain-user-text)" }} />
+                </div>
+              )}
+            </div>
+          ),
+        )}
+
+        {isTyping && (
+          <div style={S.typingRow}>
+            <div style={S.messageAvatar(false)}>
+              <Bot size={13} style={{ color: "var(--nb-explain-accent)" }} />
+            </div>
+            <div style={S.typingBubble}>
+              <span className="nb-explain-dot-1" style={S.typingDot} />
+              <span className="nb-explain-dot-2" style={S.typingDot} />
+              <span className="nb-explain-dot-3" style={S.typingDot} />
+            </div>
+          </div>
+        )}
+
+        <div ref={messagesEndRef} />
+      </div>
+
+      {/* Input */}
+      <div style={S.inputArea}>
+        <div style={S.inputRow}>
+          <input
+            ref={inputRef}
+            type="text"
+            value={input}
+            onChange={(e) => setInput(e.target.value)}
+            onKeyDown={handleKeyDown}
+            placeholder="Ask a follow-up question..."
+            style={S.inputField}
+          />
+          <button
+            onClick={sendMessage}
+            disabled={!active}
+            style={S.sendBtn(active)}
+          >
+            <Send size={15} />
+          </button>
+        </div>
+        <p style={S.inputFooter}>AI-powered assistant</p>
+      </div>
+    </div>
+  );
+}
\ No newline at end of file
diff --git a/src/client/AIFloatingButton.tsx b/src/client/AIFloatingButton.tsx
new file mode 100644
index 0000000..3ca4eb8
--- /dev/null
+++ b/src/client/AIFloatingButton.tsx
@@ -0,0 +1,34 @@
+"use client";
+
+import { MessageCircleQuestion, X } from "lucide-react";
+import React from "react";
+import * as S from "./styles";
+
+type Props = {
+  isOpen: boolean;
+  onClick: () => void;
+};
+
+export default function AIFloatingButton({ isOpen, onClick }: Props) {
+  return (
+    <button
+      onClick={onClick}
+      data-nb-explain-ignore
+      style={S.fab(isOpen)}
+      onMouseEnter={(e) => {
+        e.currentTarget.style.transform = "scale(1.05)";
+      }}
+      onMouseLeave={(e) => {
+        e.currentTarget.style.transform = "scale(1)";
+      }}
+      onMouseDown={(e) => {
+        e.currentTarget.style.transform = "scale(0.95)";
+      }}
+      onMouseUp={(e) => {
+        e.currentTarget.style.transform = "scale(1.05)";
+      }}
+    >
+      {isOpen ? <X size={20} /> : <MessageCircleQuestion size={22} />}
+    </button>
+  );
+}
\ No newline at end of file
diff --git a/src/client/index.ts b/src/client/index.ts
new file mode 100644
index 0000000..7191c6e
--- /dev/null
+++ b/src/client/index.ts
@@ -0,0 +1,4 @@
+export { default as AIAssistantProvider, useAIAssistant } from "./AIAssistantProvider";
+export { default as AIChatBot } from "./AIChatBot";
+export { default as AIFloatingButton } from "./AIFloatingButton";
+export type { Message, ExplainContext } from "../types";
\ No newline at end of file
diff --git a/src/client/styles.ts b/src/client/styles.ts
new file mode 100644
index 0000000..702d152
--- /dev/null
+++ b/src/client/styles.ts
@@ -0,0 +1,353 @@
+/**
+ * All styles for netbird-explain components.
+ * Uses inline styles + CSS custom properties so the package
+ * works without any external CSS framework.
+ *
+ * Consumers can override via CSS custom properties:
+ *   --nb-explain-bg:          panel background
+ *   --nb-explain-bg-subtle:   input/message background
+ *   --nb-explain-border:      border color
+ *   --nb-explain-text:        primary text
+ *   --nb-explain-text-muted:  secondary text
+ *   --nb-explain-text-dim:    tertiary/placeholder text
+ *   --nb-explain-accent:      accent color (yellow)
+ *   --nb-explain-accent-hover: accent hover
+ *   --nb-explain-user-bg:     user message background
+ *   --nb-explain-user-text:   user message text
+ *   --nb-explain-radius:      border radius
+ *   --nb-explain-font:        font family
+ */
+
+export const CSS_VARS = `
+  :root {
+    --nb-explain-bg: #0a0a0f;
+    --nb-explain-bg-subtle: rgba(255,255,255,0.06);
+    --nb-explain-bg-hover: rgba(255,255,255,0.08);
+    --nb-explain-border: rgba(255,255,255,0.1);
+    --nb-explain-text: #f0f0f5;
+    --nb-explain-text-muted: #9ca3af;
+    --nb-explain-text-dim: #6b7280;
+    --nb-explain-accent: #eab308;
+    --nb-explain-accent-hover: #facc15;
+    --nb-explain-accent-glow: rgba(234,179,8,0.15);
+    --nb-explain-user-bg: #4f46e5;
+    --nb-explain-user-text: #ffffff;
+    --nb-explain-user-glow: rgba(79,70,229,0.25);
+    --nb-explain-radius: 12px;
+    --nb-explain-radius-sm: 8px;
+    --nb-explain-radius-xs: 6px;
+    --nb-explain-font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
+    --nb-explain-shadow: 0 25px 50px -12px rgba(0,0,0,0.5), 0 0 0 1px rgba(255,255,255,0.05);
+    --nb-explain-banner-bg: rgba(234,179,8,0.92);
+    --nb-explain-banner-text: #000000;
+    --nb-explain-error-text: #f87171;
+  }
+`;
+
+// --- Chat Panel ---
+
+export const chatPanel: React.CSSProperties = {
+  position: "fixed",
+  bottom: 80,
+  right: 20,
+  zIndex: 9998,
+  width: 420,
+  height: 600,
+  display: "flex",
+  flexDirection: "column",
+  borderRadius: "var(--nb-explain-radius)",
+  border: "1px solid var(--nb-explain-border)",
+  background: "var(--nb-explain-bg)",
+  boxShadow: "var(--nb-explain-shadow)",
+  fontFamily: "var(--nb-explain-font)",
+  overflow: "hidden",
+  animation: "nb-explain-slide-up 0.2s ease-out",
+};
+
+export const chatHeader: React.CSSProperties = {
+  display: "flex",
+  alignItems: "center",
+  justifyContent: "space-between",
+  padding: "12px 16px",
+  borderBottom: "1px solid var(--nb-explain-border)",
+};
+
+export const chatHeaderLeft: React.CSSProperties = {
+  display: "flex",
+  alignItems: "center",
+  gap: 10,
+};
+
+export const chatHeaderIcon: React.CSSProperties = {
+  width: 28,
+  height: 28,
+  borderRadius: "var(--nb-explain-radius-sm)",
+  background: "var(--nb-explain-accent-glow)",
+  display: "flex",
+  alignItems: "center",
+  justifyContent: "center",
+};
+
+export const chatHeaderTitle: React.CSSProperties = {
+  fontSize: 14,
+  fontWeight: 600,
+  color: "var(--nb-explain-text)",
+  lineHeight: 1,
+  margin: 0,
+};
+
+export const chatHeaderSubtitle: React.CSSProperties = {
+  fontSize: 11,
+  color: "var(--nb-explain-text-dim)",
+};
+
+export const chatCloseBtn: React.CSSProperties = {
+  padding: 6,
+  borderRadius: "var(--nb-explain-radius-xs)",
+  color: "var(--nb-explain-text-dim)",
+  background: "none",
+  border: "none",
+  cursor: "pointer",
+  display: "flex",
+  alignItems: "center",
+  transition: "color 0.15s, background 0.15s",
+};
+
+// --- Messages ---
+
+export const messagesArea: React.CSSProperties = {
+  flex: 1,
+  overflowY: "auto",
+  padding: "16px",
+  display: "flex",
+  flexDirection: "column",
+  gap: 16,
+};
+
+export const emptyState: React.CSSProperties = {
+  display: "flex",
+  flexDirection: "column",
+  alignItems: "center",
+  justifyContent: "center",
+  height: "100%",
+  textAlign: "center",
+  gap: 12,
+  opacity: 0.5,
+};
+
+export const emptyStateTitle: React.CSSProperties = {
+  fontSize: 14,
+  color: "var(--nb-explain-text-muted)",
+  fontWeight: 500,
+  margin: 0,
+};
+
+export const emptyStateHint: React.CSSProperties = {
+  fontSize: 12,
+  color: "var(--nb-explain-text-dim)",
+  marginTop: 4,
+};
+
+// Context badge
+export const contextBadge: React.CSSProperties = {
+  display: "flex",
+  justifyContent: "center",
+};
+
+export const contextBadgeInner: React.CSSProperties = {
+  fontSize: 11,
+  color: "var(--nb-explain-text-dim)",
+  background: "var(--nb-explain-bg-subtle)",
+  borderRadius: 20,
+  padding: "4px 12px",
+  display: "flex",
+  alignItems: "center",
+  gap: 6,
+};
+
+// Message row
+export const messageRow = (isUser: boolean): React.CSSProperties => ({
+  display: "flex",
+  gap: 10,
+  justifyContent: isUser ? "flex-end" : "flex-start",
+});
+
+export const messageAvatar = (isUser: boolean): React.CSSProperties => ({
+  width: 24,
+  height: 24,
+  borderRadius: "var(--nb-explain-radius-xs)",
+  background: isUser ? "var(--nb-explain-user-glow)" : "var(--nb-explain-accent-glow)",
+  display: "flex",
+  alignItems: "center",
+  justifyContent: "center",
+  flexShrink: 0,
+  marginTop: 2,
+});
+
+export const messageBubble = (isUser: boolean): React.CSSProperties => ({
+  maxWidth: "85%",
+  borderRadius: "var(--nb-explain-radius-sm)",
+  padding: "8px 12px",
+  fontSize: 14,
+  lineHeight: 1.6,
+  background: isUser ? "var(--nb-explain-user-bg)" : "var(--nb-explain-bg-subtle)",
+  color: isUser ? "var(--nb-explain-user-text)" : "var(--nb-explain-text)",
+  wordBreak: "break-word",
+});
+
+export const messageBold: React.CSSProperties = {
+  fontWeight: 600,
+  color: "var(--nb-explain-text)",
+};
+
+// Typing indicator
+export const typingRow: React.CSSProperties = {
+  display: "flex",
+  gap: 10,
+};
+
+export const typingBubble: React.CSSProperties = {
+  background: "var(--nb-explain-bg-subtle)",
+  borderRadius: "var(--nb-explain-radius-sm)",
+  padding: "12px 16px",
+  display: "flex",
+  gap: 6,
+};
+
+export const typingDot: React.CSSProperties = {
+  width: 6,
+  height: 6,
+  borderRadius: "50%",
+  background: "var(--nb-explain-text-dim)",
+};
+
+// --- Input area ---
+
+export const inputArea: React.CSSProperties = {
+  padding: "12px 16px",
+  borderTop: "1px solid var(--nb-explain-border)",
+};
+
+export const inputRow: React.CSSProperties = {
+  display: "flex",
+  alignItems: "center",
+  gap: 8,
+  background: "var(--nb-explain-bg-subtle)",
+  borderRadius: "var(--nb-explain-radius-sm)",
+  padding: "8px 12px",
+};
+
+export const inputField: React.CSSProperties = {
+  flex: 1,
+  background: "none",
+  border: "none",
+  outline: "none",
+  fontSize: 14,
+  color: "var(--nb-explain-text)",
+  fontFamily: "var(--nb-explain-font)",
+};
+
+export const sendBtn = (active: boolean): React.CSSProperties => ({
+  padding: 6,
+  borderRadius: "var(--nb-explain-radius-xs)",
+  background: "none",
+  border: "none",
+  cursor: active ? "pointer" : "not-allowed",
+  color: active ? "var(--nb-explain-accent)" : "var(--nb-explain-text-dim)",
+  display: "flex",
+  alignItems: "center",
+  transition: "color 0.15s",
+  opacity: active ? 1 : 0.5,
+});
+
+export const inputFooter: React.CSSProperties = {
+  fontSize: 10,
+  color: "var(--nb-explain-text-dim)",
+  textAlign: "center",
+  marginTop: 6,
+};
+
+// --- Floating button ---
+
+export const fab = (isOpen: boolean): React.CSSProperties => ({
+  position: "fixed",
+  bottom: 20,
+  right: 20,
+  zIndex: 9997,
+  width: 48,
+  height: 48,
+  borderRadius: "50%",
+  display: "flex",
+  alignItems: "center",
+  justifyContent: "center",
+  border: "none",
+  cursor: "pointer",
+  transition: "transform 0.2s, box-shadow 0.2s",
+  boxShadow: "0 4px 20px rgba(0,0,0,0.3)",
+  background: isOpen
+    ? "var(--nb-explain-bg-hover)"
+    : "linear-gradient(135deg, var(--nb-explain-accent), #f97316)",
+  color: isOpen ? "var(--nb-explain-text-muted)" : "#fff",
+});
+
+// --- Banner ---
+
+export const banner: React.CSSProperties = {
+  position: "fixed",
+  top: 12,
+  left: "50%",
+  transform: "translateX(-50%)",
+  zIndex: 9996,
+  background: "var(--nb-explain-banner-bg)",
+  color: "var(--nb-explain-banner-text)",
+  fontSize: 14,
+  fontWeight: 500,
+  padding: "6px 16px",
+  borderRadius: 20,
+  boxShadow: "0 4px 20px rgba(234,179,8,0.3)",
+  display: "flex",
+  alignItems: "center",
+  gap: 8,
+  fontFamily: "var(--nb-explain-font)",
+  animation: "nb-explain-fade-in 0.2s ease-out",
+};
+
+export const bannerCancel: React.CSSProperties = {
+  marginLeft: 4,
+  color: "rgba(0,0,0,0.5)",
+  background: "none",
+  border: "none",
+  cursor: "pointer",
+  textDecoration: "underline",
+  fontSize: 12,
+  fontFamily: "var(--nb-explain-font)",
+};
+
+// --- Animations (injected as <style>) ---
+
+export const ANIMATIONS = `
+  @keyframes nb-explain-slide-up {
+    from { opacity: 0; transform: translateY(8px); }
+    to { opacity: 1; transform: translateY(0); }
+  }
+  @keyframes nb-explain-fade-in {
+    from { opacity: 0; transform: translateX(-50%) translateY(-4px); }
+    to { opacity: 1; transform: translateX(-50%) translateY(0); }
+  }
+  @keyframes nb-explain-bounce {
+    0%, 80%, 100% { transform: translateY(0); }
+    40% { transform: translateY(-4px); }
+  }
+  .nb-explain-dot-1 { animation: nb-explain-bounce 1.2s infinite; animation-delay: 0ms; }
+  .nb-explain-dot-2 { animation: nb-explain-bounce 1.2s infinite; animation-delay: 150ms; }
+  .nb-explain-dot-3 { animation: nb-explain-bounce 1.2s infinite; animation-delay: 300ms; }
+`;
+
+export const HIGHLIGHT_STYLES = `
+  [data-nb-explain-highlight] {
+    outline: 2px solid rgba(234, 179, 8, 0.7) !important;
+    border-radius: 6px;
+    cursor: help !important;
+    transition: outline 0.1s ease;
+  }
+`;
\ No newline at end of file
diff --git a/src/server/handler.ts b/src/server/handler.ts
new file mode 100644
index 0000000..f0df66d
--- /dev/null
+++ b/src/server/handler.ts
@@ -0,0 +1,158 @@
+import type { Message } from "../types";
+import { AnthropicProvider } from "./providers/anthropic";
+import { OpenAIProvider } from "./providers/openai";
+import type { LLMProvider } from "./providers/types";
+
+export type AssistantConfig = {
+  provider: "anthropic" | "openai";
+  apiKey: string;
+  model?: string;
+  systemPrompt?: string;
+};
+
+type HandlerOptions = {
+  apiKey?: string;
+};
+
+type ChatRequest = {
+  messages: Message[];
+};
+
+type ChatResponse = {
+  reply: string;
+};
+
+interface IncomingRequest {
+  headers: Record<string, string | string[] | undefined> | { get(name: string): string | null };
+  body?: unknown;
+  method?: string;
+  on?(event: string, callback: (...args: unknown[]) => void): unknown;
+}
+
+interface OutgoingResponse {
+  status?(code: number): Pick<OutgoingResponse, "json" | "end">;
+  statusCode?: number;
+  json?(data: unknown): void;
+  end?(data?: string): void;
+  setHeader?(name: string, value: string): void;
+  writeHead?(statusCode: number, headers?: Record<string, string>): void;
+}
+
+function getHeader(req: IncomingRequest, name: string): string | null {
+  if (typeof req.headers === "object" && req.headers !== null) {
+    if ("get" in req.headers && typeof req.headers.get === "function") {
+      return req.headers.get(name);
+    }
+    const headers = req.headers as Record<string, string | string[] | undefined>;
+    const value = headers[name] ?? headers[name.toLowerCase()];
+    if (Array.isArray(value)) return value[0] ?? null;
+    return value ?? null;
+  }
+  return null;
+}
+
+function sendJson(res: OutgoingResponse, statusCode: number, data: unknown): void {
+  if (typeof res.status === "function" && typeof res.json === "function") {
+    const chained = res.status(statusCode);
+    if (chained && typeof chained.json === "function") {
+      chained.json(data);
+      return;
+    }
+  }
+  if (typeof res.writeHead === "function" && typeof res.end === "function") {
+    res.writeHead(statusCode, { "Content-Type": "application/json" });
+    res.end(JSON.stringify(data));
+    return;
+  }
+  if (typeof res.end === "function") {
+    if (res.statusCode !== undefined) res.statusCode = statusCode;
+    res.end(JSON.stringify(data));
+  }
+}
+
+async function parseBody(req: IncomingRequest): Promise<unknown> {
+  if (req.body !== undefined && req.body !== null) {
+    return req.body;
+  }
+  if (typeof req.on === "function") {
+    const onFn = req.on.bind(req);
+    return new Promise((resolve, reject) => {
+      const chunks: string[] = [];
+      onFn("data", (chunk: unknown) => chunks.push(String(chunk)));
+      onFn("end", () => {
+        try {
+          resolve(JSON.parse(chunks.join("")));
+        } catch {
+          reject(new Error("Invalid JSON body"));
+        }
+      });
+      onFn("error", reject);
+    });
+  }
+  throw new Error("Unable to parse request body");
+}
+
+function createProvider(config: AssistantConfig): LLMProvider {
+  switch (config.provider) {
+    case "anthropic":
+      return new AnthropicProvider({ apiKey: config.apiKey, model: config.model });
+    case "openai":
+      return new OpenAIProvider({ apiKey: config.apiKey, model: config.model });
+    default:
+      throw new Error(`Unknown provider: ${config.provider}`);
+  }
+}
+
+export function createAssistant(config: AssistantConfig) {
+  const provider = createProvider(config);
+
+  async function chat(req: ChatRequest): Promise<ChatResponse> {
+    if (!req.messages || !Array.isArray(req.messages) || req.messages.length === 0) {
+      throw new Error("messages array is required and must not be empty");
+    }
+    const reply = await provider.chat(req.messages, config.systemPrompt);
+    return { reply };
+  }
+
+  function handler(opts?: HandlerOptions) {
+    return async (req: IncomingRequest, res: OutgoingResponse): Promise<void> => {
+      try {
+        if (opts?.apiKey) {
+          const authHeader = getHeader(req, "Authorization") || getHeader(req, "authorization");
+          const token = authHeader?.startsWith("Bearer ") ? authHeader.slice(7) : null;
+          if (token !== opts.apiKey) {
+            sendJson(res, 401, { error: "Unauthorized" });
+            return;
+          }
+        }
+
+        let body: unknown;
+        try {
+          body = await parseBody(req);
+        } catch {
+          sendJson(res, 400, { error: "Invalid request body" });
+          return;
+        }
+
+        const { messages } = body as { messages?: Message[] };
+        if (!messages || !Array.isArray(messages) || messages.length === 0) {
+          sendJson(res, 400, { error: "messages array is required and must not be empty" });
+          return;
+        }
+
+        try {
+          const result = await chat({ messages });
+          sendJson(res, 200, result);
+        } catch (err) {
+          const message = err instanceof Error ? err.message : "LLM request failed";
+          sendJson(res, 502, { error: message });
+        }
+      } catch (err) {
+        const message = err instanceof Error ? err.message : "Internal server error";
+        sendJson(res, 500, { error: message });
+      }
+    };
+  }
+
+  return { chat, handler };
+}
\ No newline at end of file
diff --git a/src/server/index.ts b/src/server/index.ts
new file mode 100644
index 0000000..28509d9
--- /dev/null
+++ b/src/server/index.ts
@@ -0,0 +1,5 @@
+export { createAssistant } from "./handler";
+export type { AssistantConfig } from "./handler";
+export { AnthropicProvider } from "./providers/anthropic";
+export { OpenAIProvider } from "./providers/openai";
+export type { LLMProvider, ProviderConfig } from "./providers/types";
\ No newline at end of file
diff --git a/src/server/providers/anthropic.ts b/src/server/providers/anthropic.ts
new file mode 100644
index 0000000..043902b
--- /dev/null
+++ b/src/server/providers/anthropic.ts
@@ -0,0 +1,53 @@
+import type { Message } from "../../types";
+import type { LLMProvider, ProviderConfig } from "./types";
+
+export class AnthropicProvider implements LLMProvider {
+  private apiKey: string;
+  private model: string;
+
+  constructor(config: ProviderConfig) {
+    this.apiKey = config.apiKey;
+    this.model = config.model || "claude-sonnet-4-20250514";
+  }
+
+  async chat(messages: Message[], systemPrompt?: string): Promise<string> {
+    const anthropicMessages = messages.map((m) => ({
+      role: m.role === "context" || m.role === "system" ? ("user" as const) : m.role,
+      content: m.role === "context" ? `[Context]: ${m.content}` : m.content,
+    }));
+
+    const body: Record<string, unknown> = {
+      model: this.model,
+      max_tokens: 4096,
+      messages: anthropicMessages,
+    };
+
+    if (systemPrompt) {
+      body.system = systemPrompt;
+    }
+
+    const response = await fetch("https://api.anthropic.com/v1/messages", {
+      method: "POST",
+      headers: {
+        "Content-Type": "application/json",
+        "x-api-key": this.apiKey,
+        "anthropic-version": "2023-06-01",
+      },
+      body: JSON.stringify(body),
+    });
+
+    if (!response.ok) {
+      const text = await response.text();
+      throw new Error(`Anthropic API error ${response.status}: ${text}`);
+    }
+
+    const data = await response.json();
+    const textBlock = data.content?.find(
+      (block: { type: string }) => block.type === "text",
+    );
+    if (!textBlock) {
+      throw new Error("No text content in Anthropic response");
+    }
+    return textBlock.text;
+  }
+}
\ No newline at end of file
diff --git a/src/server/providers/openai.ts b/src/server/providers/openai.ts
new file mode 100644
index 0000000..90a177a
--- /dev/null
+++ b/src/server/providers/openai.ts
@@ -0,0 +1,55 @@
+import type { Message } from "../../types";
+import type { LLMProvider, ProviderConfig } from "./types";
+
+export class OpenAIProvider implements LLMProvider {
+  private apiKey: string;
+  private model: string;
+
+  constructor(config: ProviderConfig) {
+    this.apiKey = config.apiKey;
+    this.model = config.model || "gpt-4o";
+  }
+
+  async chat(messages: Message[], systemPrompt?: string): Promise<string> {
+    const openaiMessages: Array<{ role: string; content: string }> = [];
+
+    if (systemPrompt) {
+      openaiMessages.push({ role: "system", content: systemPrompt });
+    }
+
+    for (const m of messages) {
+      if (m.role === "context") {
+        openaiMessages.push({ role: "user", content: `[Context]: ${m.content}` });
+      } else if (m.role === "system") {
+        openaiMessages.push({ role: "user", content: m.content });
+      } else {
+        openaiMessages.push({ role: m.role, content: m.content });
+      }
+    }
+
+    const response = await fetch("https://api.openai.com/v1/chat/completions", {
+      method: "POST",
+      headers: {
+        "Content-Type": "application/json",
+        Authorization: `Bearer ${this.apiKey}`,
+      },
+      body: JSON.stringify({
+        model: this.model,
+        messages: openaiMessages,
+        max_tokens: 4096,
+      }),
+    });
+
+    if (!response.ok) {
+      const text = await response.text();
+      throw new Error(`OpenAI API error ${response.status}: ${text}`);
+    }
+
+    const data = await response.json();
+    const choice = data.choices?.[0];
+    if (!choice?.message?.content) {
+      throw new Error("No content in OpenAI response");
+    }
+    return choice.message.content;
+  }
+}
\ No newline at end of file
diff --git a/src/server/providers/types.ts b/src/server/providers/types.ts
new file mode 100644
index 0000000..fd18bb0
--- /dev/null
+++ b/src/server/providers/types.ts
@@ -0,0 +1,10 @@
+import type { Message } from "../../types";
+
+export interface LLMProvider {
+  chat(messages: Message[], systemPrompt?: string): Promise<string>;
+}
+
+export type ProviderConfig = {
+  apiKey: string;
+  model?: string;
+};
\ No newline at end of file
diff --git a/src/types.ts b/src/types.ts
new file mode 100644
index 0000000..2ffcbc9
--- /dev/null
+++ b/src/types.ts
@@ -0,0 +1,11 @@
+export type Message = {
+  id?: string;
+  role: "user" | "assistant" | "context" | "system";
+  content: string;
+};
+
+export type ExplainContext = {
+  modalName?: string;
+  pageName?: string;
+  docsUrls?: string[];
+};
\ No newline at end of file
diff --git a/tsconfig.json b/tsconfig.json
new file mode 100644
index 0000000..e6c2b1b
--- /dev/null
+++ b/tsconfig.json
@@ -0,0 +1,22 @@
+{
+  "compilerOptions": {
+    "target": "ES2020",
+    "module": "ESNext",
+    "moduleResolution": "bundler",
+    "lib": ["ES2020", "DOM", "DOM.Iterable"],
+    "jsx": "react-jsx",
+    "declaration": true,
+    "declarationMap": true,
+    "sourceMap": true,
+    "outDir": "./dist",
+    "rootDir": "./src",
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "forceConsistentCasingInFileNames": true,
+    "resolveJsonModule": true,
+    "isolatedModules": true
+  },
+  "include": ["src"],
+  "exclude": ["node_modules", "dist"]
+}
\ No newline at end of file