Gemini-Kit (Node.js)

Gemini-Kit is an unofficial Node.js wrapper for Google Gemini, developed through reverse-engineering.
It uses your browser cookie values to communicate with Google Gemini — no official API key required.

⚠️ For testing / educational purposes only. Reverse-engineering Google services may violate their Terms of Service.

✨ Features

| Feature | Description | |---|---| | 💬 Single & Multi-turn Chat | Ask questions and maintain conversation context | | 🖼️ Image Fetching | Extract inline image URLs returned by Gemini | | 🎨 Generated Image Extraction | Save AI-generated images from responses | | 📸 Image Upload | Upload images and ask questions about them | | 🔊 Text-to-Speech | Convert any Gemini response to audio bytes | | 🔗 Share Conversations | Generate shareable conversation links | | 🍪 Cookie Parsing | Parse cookies from Chrome net-export log files |

📦 Installation

npm install @k.nirmal/gemini-kit

🍪 Get Cookie File (chrome-net-export-log)

For a detailed video guide, click here.

1. Close All Tabs

Ensure all tabs are closed in Google Chrome.

2. Access Network Export

• Open a new tab and navigate to chrome://net-export/.

3. Configure Logging Settings

• Check the box labelled "Include cookies and credentials".
• Set the Maximum log size to 1 MB.
• Click "Start logging".

4. Perform Actions

• Open a new tab and go to gemini.google.com.
• Log in to your Gemini account.
• Send a sample message and wait for Gemini's response.

5. Stop Logging

• Return to the logging tab and click "Stop logging".

6. Save the JSON File

• The cookies will be saved in a JSON file (e.g. chrome-net-export-log.json).

7. Extract Cookies in Node.js

const { getCookiesFromFile } = require('geminikit');
const fs = require('fs');

const raw = fs.readFileSync('chrome-net-export-log.json', 'utf8');
const cookies = getCookiesFromFile(raw);
console.log(cookies);

🚀 Quick Start

const { createGemini, getCookiesFromFile } = require('geminikit');
const fs = require('fs');

(async () => {
  const cookies = getCookiesFromFile(fs.readFileSync('chrome-net-export-log.json', 'utf8'));
  const gemini = await createGemini(cookies);

  const res = await gemini.ask('Hello! Who are you?');
  console.log(res.text);
})();

📖 API Reference

createGemini(cookies) → Promise<Gemini>

Factory helper. Creates and initialises a Gemini client in one call.

const gemini = await createGemini(cookies);

new Gemini(cookies)

Construct a client manually. Call await gemini.ready() before using any methods.

const { Gemini } = require('geminikit');
const gemini = new Gemini(cookies);
await gemini.ready();

getCookiesFromFile(text) → Object

Parse cookies from the raw text content of a Chrome net-export-log JSON file.

const { getCookiesFromFile } = require('geminikit');
const cookies = getCookiesFromFile(fs.readFileSync('chrome-net-export-log.json', 'utf8'));

gemini.ask(text, [opts]) → Promise<Object>

Send a message and get a structured response.

Parameters:

| Name | Type | Description | |---|---|---| | text | string | The message to send | | opts.user | Object | Previous response (for conversation continuity) | | opts.photo | [name, url] | Photo array for vision questions |

Returns:

{
  text: string,               // Gemini's response text
  conversation_id: string,    // Conversation ID (pass back in opts.user)
  response_id: string,
  choice_id: string,
  req_id: number,
  fsid: string,
  bott: string,
  SNlM0e: string,
  image_urls: string[],           // Inline image URLs in the response
  generated_image_urls: string[]  // AI-generated image URLs
}

Example — Single message:

const res = await gemini.ask('Tell me a joke');
console.log(res.text);

Example — Continuous conversation:

const res1 = await gemini.ask('Tell me a joke');
console.log(res1.text);

const res2 = await gemini.ask('Another one!', { user: res1 });
console.log(res2.text);

Example — Ask with a photo:

const fs = require('fs');
const imgBytes = fs.readFileSync('cat.jpg');
const imgUrl = await gemini.uploadImage(imgBytes);

const res = await gemini.ask('What is in this photo?', {
  photo: ['cat.jpg', imgUrl]
});
console.log(res.text);

gemini.share(conversationId, responseId, choiceId, reqId, fsid, [opts]) → Promise<string>

Generate a shareable URL for a conversation.

Parameters:

| Name | Type | Description | |---|---|---| | conversationId | string | From response object | | responseId | string | From response object | | choiceId | string | From response object | | reqId | number | From response object | | fsid | string | From response object | | opts.title | string | Custom share title (optional) |

Example:

const res = await gemini.ask('Hi!');
const url = await gemini.share(
  res.conversation_id,
  res.response_id,
  res.choice_id,
  res.req_id,
  res.fsid,
  { title: 'My Gemini Chat' }
);
console.log(url); // https://gemini.google.com/share/...

gemini.speech(text, [opts]) → Promise<Buffer>

Convert text to speech and return raw audio bytes (WAV format).

Parameters:

| Name | Type | Default | Description | |---|---|---|---| | text | string | — | Text to convert | | opts.langCode | string | "en-GB" | BCP-47 language code |

Example:

const fs = require('fs');

const audio = await gemini.speech('Hello, world!');
fs.writeFileSync('output.wav', audio);

With a different language:

const audio = await gemini.speech('Bonjour!', { langCode: 'fr-FR' });
fs.writeFileSync('output.wav', audio);

gemini.uploadImage(imageBuffer) → Promise<string>

Upload an image buffer to Google's servers and get a URL back.
Use the returned URL with gemini.ask() via the photo option.

Example:

const fs = require('fs');
const imgBytes = fs.readFileSync('photo.jpg');
const url = await gemini.uploadImage(imgBytes);
console.log('Uploaded to:', url);

gemini.getImgBytes(url) → Promise<Buffer>

Download raw image bytes from a URL using the authenticated session.
Useful for saving image_urls or generated_image_urls from ask().

Example:

const res = await gemini.ask('Show me some wallpapers');
console.log(res.text);

for (const url of res.image_urls) {
  const bytes = await gemini.getImgBytes(url);
  const name = url.split('/').pop();
  require('fs').writeFileSync(name, bytes);
}

gemini.refreshCookies() → Promise<[string, string]>

Re-fetch SNlM0e and bott tokens from the Gemini homepage.
Called automatically on construction. Useful if your session expires.

await gemini.refreshCookies();

gemini.getCookies() → Object

Return the cookies currently in use.

const cookies = gemini.getCookies();

💡 Full Examples

Save All Response Images

const { createGemini, getCookiesFromFile } = require('geminikit');
const fs = require('fs');

(async () => {
  const cookies = getCookiesFromFile(fs.readFileSync('chrome-net-export-log.json', 'utf8'));
  const gemini = await createGemini(cookies);

  const res = await gemini.ask('Send me some nature wallpapers');
  console.log(res.text);

  for (const url of res.image_urls) {
    const name = url.split('/').pop();
    const bytes = await gemini.getImgBytes(url);
    fs.writeFileSync(name, bytes);
    console.log('Saved:', name);
  }
})();

Save AI-Generated Images

(async () => {
  const res = await gemini.ask('Generate an image of a cat holding a rose.');
  console.log(res.text);

  for (const url of res.generated_image_urls) {
    const name = url.split('/').pop().slice(0, 10) + '.png';
    const bytes = await gemini.getImgBytes(url);
    fs.writeFileSync(name, bytes);
    console.log('Saved generated image:', name);
  }
})();

Text-to-Speech to File

(async () => {
  const audio = await gemini.speech('Welcome to GeminiKit!');
  fs.writeFileSync('welcome.wav', audio);
  console.log('Audio saved to welcome.wav');
})();

🔢 Response Object Fields

| Field | Type | Description | |---|---|---| | text | string | Gemini's text reply | | conversation_id | string | Continue the conversation | | response_id | string | ID of this response | | choice_id | string | Selected response variant ID | | req_id | number | Request ID | | fsid | string | File session ID | | bott | string | Internal Gemini version token | | SNlM0e | string | CSRF/session token | | image_urls | string[] | Inline image URLs from response | | generated_image_urls | string[] | AI-generated image URLs |

📁 Project Structure

geminikit/
├── index.js          # Package entry point
├── src/
│   ├── gemini.js     # Gemini class (all API methods)
│   ├── headers.js    # HTTP headers
│   └── helpers.js    # Cookie parsing & utilities
├── package.json
├── README.md
└── LICENSE

🤝 Contributing

Pull requests are welcome! Please open an issue first to discuss what you would like to change.

📄 License

MIT — © Nirmal Gmage