# Headroom.js Licensing Information: MIT License Terms and Usage Guide

> Understand headroom.js licensing with this MIT License guide. Discover terms for commercial use modification and distribution of this popular JavaScript library. Get the details you need.

- Repository: [Tejas Chopra/headroom](https://github.com/chopratejas/headroom)
- Tags: licensing-information
- Published: 2026-06-19

---

**The headroom.js package is released under the MIT License, a permissive open-source license that permits commercial use, modification, and distribution provided the original copyright notice is preserved.**

The `chopratejas/headroom` repository distributes its JavaScript SDK under the MIT License, making it available for integration into both open-source and proprietary applications. This licensing model imposes minimal restrictions while ensuring proper attribution to the original authors. Understanding the specific terms and source file locations helps ensure compliant usage of the AI prompt compression library.

## Understanding the MIT License for Headroom.js

The MIT License governs all code within the headroom repository, including the JavaScript SDK distributed as `headroom-ai` on npm. This permissive license allows developers to freely use the software while requiring preservation of copyright notices and license text.

### License Permissions and Requirements

According to the [`LICENSE`](https://github.com/chopratejas/headroom/blob/main/LICENSE) file in the repository root, the MIT License grants you the right to:

- Use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the software
- Include the software in proprietary projects without disclosing your source code

The sole requirement demands that the original copyright notice and permission notice appear in all copies or substantial portions of the software.

### License Declaration in Package Files

The [[`sdk/typescript/package.json`](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/package.json)](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/package.json) explicitly declares `"license": "MIT"`, confirming the package's licensing status for npm registries and automated license checking tools.

## Installing the MIT-Licensed JavaScript SDK

Install the package via npm to begin using the MIT-licensed code in your projects:

```bash
npm install headroom-ai

```

## Code Implementation Examples

The following examples demonstrate practical usage of the MIT-licensed SDK components in production environments.

### Basic Prompt Compression

Use the `compress` function from `headroom-ai` to reduce token counts before sending prompts to LLMs:

```javascript
import { compress } from 'headroom-ai';

// Original prompt (large)
const prompt = `
  You are a friendly AI assistant...
  ... (many tokens)
`;

// Compress to fit model limits
const { compressed, remaining } = await compress(prompt, {
  // optional: target token budget
  targetTokens: 2000,
});

console.log('Compressed prompt:', compressed);
console.log('Tokens saved:', remaining);

```

The compression logic resides in [[`sdk/typescript/src/compress.ts`](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/src/compress.ts)](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/src/compress.ts).

### Vercel AI Middleware Integration

Implement automatic compression in Vercel AI applications using the middleware pattern:

```javascript
import { headroomMiddleware } from 'headroom-ai/vercel-ai';

// In your Vercel AI route
export default async function handler(req) {
  await headroomMiddleware(req);
  // now `req.body.messages` are automatically compressed
  // … proceed with your LLM call
}

```

This middleware is implemented in [[`sdk/typescript/src/vercel-ai/index.ts`](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/src/vercel-ai/index.ts)](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/src/vercel-ai/index.ts).

### OpenAI Provider Setup

Configure the `HeadroomClient` with OpenAI integration for automatic optimization:

```javascript
import { HeadroomClient, OpenAIProvider } from 'headroom-ai';

const client = new HeadroomClient({
  provider: new OpenAIProvider({ apiKey: process.env.OPENAI_API_KEY }),
  // compress automatically on each request
  mode: 'optimize',
});

const response = await client.chat.completions.create({
  model: 'gpt-4o-mini',
  messages: [{ role: 'user', content: hugeUserMessage }],
});

```

The OpenAI wrapper is defined in [[`sdk/typescript/src/openai.ts`](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/src/openai.ts)](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/src/openai.ts).

## Key Source Files Under MIT License

All source files in the `chopratejas/headroom` repository fall under the MIT License:

- **License Declaration**: [`LICENSE`](https://github.com/chopratejas/headroom/blob/main/LICENSE) — Contains the full MIT legal text at the repository root
- **Package Manifest**: [[`sdk/typescript/package.json`](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/package.json)](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/package.json) — Declares the MIT license metadata for npm distribution
- **Core Module Example**: [[`plugins/openclaw/hook-shim/handler.js`](https://github.com/chopratejas/headroom/blob/main/plugins/openclaw/hook-shim/handler.js)](https://github.com/chopratejas/headroom/blob/main/plugins/openclaw/hook-shim/handler.js) — Demonstrates MIT-licensed JavaScript modules
- **Compression Engine**: [[`sdk/typescript/src/compress.ts`](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/src/compress.ts)](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/src/compress.ts) — Implements token-budget compression logic
- **Vercel Integration**: [[`sdk/typescript/src/vercel-ai/index.ts`](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/src/vercel-ai/index.ts)](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/src/vercel-ai/index.ts) — Vercel AI runtime integration
- **OpenAI Client**: [[`sdk/typescript/src/openai.ts`](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/src/openai.ts)](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/src/openai.ts) — OpenAI provider implementation

## Summary

- **Headroom.js uses the MIT License**, a permissive open-source license that allows commercial and private use without restriction
- **The license file** is located at the repository root in `LICENSE` and declared in [`sdk/typescript/package.json`](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/package.json)
- **You may modify, distribute, and sublicense** the code provided you include the original copyright notice and license text
- **All source files** in the `chopratejas/headroom` repository, including the TypeScript SDK and JavaScript modules, fall under this single license
- **No warranty is provided** — the software is provided "as is" without liability from the authors

## Frequently Asked Questions

### Can I use headroom.js in commercial projects?

Yes. The MIT License explicitly permits commercial use, including incorporation into proprietary software and selling copies of the software. You must only retain the original copyright notice and license text found in the [`LICENSE`](https://github.com/chopratejas/headroom/blob/main/LICENSE) file.

### Where is the license file located in the headroom repository?

The complete MIT License text is located in the [`LICENSE`](https://github.com/chopratejas/headroom/blob/main/LICENSE) file at the repository root. The TypeScript SDK's [`package.json`](https://github.com/chopratejas/headroom/blob/main/package.json) at [[`sdk/typescript/package.json`](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/package.json)](https://github.com/chopratejas/headroom/blob/main/sdk/typescript/package.json) also confirms the MIT licensing for npm distribution.

### Do I need to open-source my code if I use headroom.js?

No. The MIT License does not impose copyleft requirements. You can use, modify, and distribute the software in proprietary closed-source projects without disclosing your source code, provided you include the MIT License notice and copyright statement from the original authors.

### What are the limitations of the MIT License for headroom.js?

The MIT License provides the software "as is" without warranty of any kind, express or implied. The authors are not liable for any claims, damages, or other liability arising from the use of the software. You assume all risk when using headroom.js in production environments.