GitHub - kstonekuan/simple-chromium-ai: A lightweight TypeScript wrapper for Chrome's built-in AI Prompt API that trades flexibility for simplicity and type safety.

npm install simple-chromium-ai

import ChromiumAI from 'simple-chromium-ai';

// Initialize once
const ai = await ChromiumAI.initialize("You are a helpful assistant");

// Simple prompt
const response = await ChromiumAI.prompt(ai, "Write a haiku");

// Or use the Safe API for error handling
const safeResult = await ChromiumAI.Safe.initialize("You are a helpful assistant");
safeResult.match(
  async (ai) => {
    const safeResponse = await ChromiumAI.Safe.prompt(ai, "Write a haiku");
    safeResponse.match(
      (value) => console.log(value),
      (error) => console.error(error.message)
    );
  },
  (error) => console.error(error.message)
);

cd demo
npm install
npm run build
# Then load the demo folder as an unpacked extension in Chrome

await LanguageModel.create({
  monitor(m) {
    m.addEventListener('downloadprogress', (e) => {
      console.log(`Downloaded ${e.loaded * 100}%`);
    });
  },
});

const ai = await ChromiumAI.initialize(
  systemPrompt?: string
);

const response = await ChromiumAI.prompt(
  ai,
  "Your prompt",
  timeout?: number
);

// Create reusable session
const session = await ChromiumAI.createSession(ai);
const response1 = await session.prompt("Hello");
const response2 = await session.prompt("Follow up"); // Maintains context
session.destroy();

// Override the instance's system prompt for this session
const customSession = await ChromiumAI.createSession(ai, {
  initialPrompts: [{ role: 'system', content: 'You are a pirate' }]
});

// Or use withSession for automatic cleanup
const result = await ChromiumAI.withSession(ai, async (session) => {
  return await session.prompt("Hello");
});

const usage = await ChromiumAI.checkTokenUsage(ai, "Long text...");
console.log(`Will fit: ${usage.willFit}`);
console.log(`Tokens needed: ${usage.promptTokens}/${usage.maxTokens}`);

import { ChromiumAI } from 'simple-chromium-ai';

const result = await ChromiumAI.Safe.initialize("You are helpful");
result.match(
  async (ai) => {
    const response = await ChromiumAI.Safe.prompt(ai, "Hello");
    response.match(
      (value) => console.log(value),
      (error) => console.error("Prompt failed:", error.message)
    );
  },
  (error) => {
    console.error("Failed:", error.message);
    return;
  }
);

// ❌ Won't compile - need AI instance
await ChromiumAI.prompt("Hello");

// ✅ Correct usage
const ai = await ChromiumAI.initialize("You are helpful");
await ChromiumAI.prompt(ai, "Hello");

const ai = await ChromiumAI.initialize("You are a friendly assistant");
const response = await ChromiumAI.prompt(ai, "Tell me a joke");

try {
  const ai = await ChromiumAI.initialize("You are helpful");
  const response = await ChromiumAI.prompt(ai, "Hello!");
} catch (error) {
  console.error('Initialization failed:', error.message);
  // Error message will include instructions on how to enable Chrome AI
}

// Using the Safe API for better error handling
const result = await ChromiumAI.Safe.initialize("You are helpful");

result.match(
  async (ai) => {
    const promptResult = await ChromiumAI.Safe.prompt(ai, "Hello!");
    promptResult.match(
      (value) => console.log('Response:', value),
      (error) => console.error('Prompt failed:', error.message)
    );
  },
  (error) => {
    console.error('Initialization failed:', error.message);
    // Error message includes instructions on how to enable Chrome AI
  }
);

const usage = await ChromiumAI.checkTokenUsage(ai, longText);
if (!usage.willFit) {
  // Use shorter prompt
  const response = await ChromiumAI.prompt(ai, "Summarize briefly");
}

// Define JSON schema for the response
const schema = {
  type: "object",
  properties: {
    sentiment: {
      type: "string",
      enum: ["positive", "negative", "neutral"]
    },
    confidence: {
      type: "number",
      minimum: 0,
      maximum: 1
    },
    keywords: {
      type: "array",
      items: { type: "string" },
      maxItems: 5
    }
  },
  required: ["sentiment", "confidence", "keywords"]
};

// Create session with response constraint
const response = await ChromiumAI.prompt(
  ai, 
  "Analyze the sentiment of this text: 'I love this new feature!'",
  undefined, // no timeout
  { responseConstraint: schema }
);

// Response will be valid JSON matching the schema
const result = JSON.parse(response);
console.log(result); 
// { sentiment: "positive", confidence: 0.95, keywords: ["love", "new", "feature"] }

// Create an AbortController to cancel long-running prompts
const controller = new AbortController();

// Set up a cancel button
const cancelButton = document.getElementById('cancel');
cancelButton.onclick = () => controller.abort();

try {
  // Pass the abort signal to the prompt
  const response = await ChromiumAI.prompt(
    ai, 
    "Write a detailed analysis of quantum computing...",
    undefined, // no timeout
    { signal: controller.signal } // prompt options with abort signal
  );
  console.log(response);
} catch (error) {
  if (error.name === 'AbortError') {
    console.log('Prompt was cancelled by user');
  } else {
    console.error('Error:', error.message);
  }
}