Codebuff: An AI Coding Assistant for Terminal-Based Code Generation

Introduction

Codebuff is an open-source AI coding assistant designed to help developers generate and edit code directly from the terminal using natural language instructions. Instead of relying on a single large model, Codebuff coordinates specialized agents that work together to understand your project's architecture and make precise, validated changes. This multi-agent approach leads to better context understanding, more accurate edits, and fewer errors compared to single-model tools. For those seeking a free option, Freebuff offers a similar experience without subscriptions or credits, supported by ads.

Installation

Getting started with Codebuff is straightforward. You can install the CLI tool globally via npm:

npm install -g codebuff

Once installed, navigate to your project directory and run codebuff to start interacting with the AI assistant:

cd your-project
codebuff

For the free, ad-supported version, Freebuff, the installation is similar:

npm install -g freebuff
cd your-project
freebuff

If you plan to integrate Codebuff's capabilities into your applications, you can use the SDK:

npm install @codebuff/sdk

Examples

Codebuff simplifies complex coding tasks with simple prompts. Here are some examples of what you can ask Codebuff to do:

"Fix the SQL injection vulnerability in user registration"
"Add rate limiting to all API endpoints"
"Refactor the database connection code for better performance"

Codebuff will intelligently find relevant files, make necessary changes across your codebase, and even run tests to ensure stability.

You can also create custom agents to define specific workflows. For instance, a git-committer agent can analyze changes and craft meaningful commit messages:

export default {
  id: 'git-committer',
  displayName: 'Git Committer',
  model: 'openai/gpt-5-nano',
  toolNames: ['read_files', 'run_terminal_command', 'end_turn'],

  instructionsPrompt:
    'You create meaningful git commits by analyzing changes, reading relevant files for context, and crafting clear commit messages that explain the "why" behind changes.',

  async *handleSteps() {
    // Analyze what changed
    yield { tool: 'run_terminal_command', command: 'git diff' }
    yield { tool: 'run_terminal_command', command: 'git log --oneline -5' }

    // Stage files and create commit with good message
    yield 'STEP_ALL'
  },
}

The SDK allows you to run agents programmatically within your applications:

import { CodebuffClient } from '@codebuff/sdk'

const client = new CodebuffClient({
  apiKey: 'your-api-key',
  cwd: '/path/to/your/project',
  onError: (error) => console.error('Codebuff error:', error.message),
})

const result = await client.run({
  agent: 'base',
  prompt: 'Add error handling to all API endpoints',
  handleEvent: (event) => {
    console.log('Progress', event)
  },
})

Why use Codebuff

Codebuff offers several compelling advantages for developers:

Custom Workflows: Leverage TypeScript generators to combine AI generation with programmatic control. Agents can spawn subagents, handle conditional logic, and execute multi-step processes for highly tailored automation.
Any Model on OpenRouter: Unlike tools locked into specific models, Codebuff supports any model available on OpenRouter. This flexibility allows you to choose from a wide range of models, including Claude, GPT, Qwen, and DeepSeek, optimizing for different tasks or utilizing the latest releases without platform restrictions.
Reuse Published Agents: Accelerate development by composing existing published agents. This modularity allows you to build upon community contributions and specialized tools.
SDK for Integration: Integrate Codebuff directly into your applications, CI/CD pipelines, or embed coding assistance into your products using the provided SDK.