Context Generator for LLM

Context Generator is a PHP tool that helps developers build structured context files from various sources:

• code files,
• GitHub repositories,
• Web pages (URLs) with CSS selectors,
• and plain text.

It was created to solve a common problem: efficiently providing AI language models like ChatGPT, Claude with necessary context about your codebase.

Why You Need This

When working with AI-powered development tools context is everything.

• Code Refactoring Assistance: Want AI help refactoring a complex class? Context Generator builds a properly formatted document containing all relevant code files.

• Multiple Iteration Development: Working through several iterations with an AI helper requires constantly updating the context. Context Generator automates this process.

• Documentation Generation: Transform your codebase into comprehensive documentation by combining source code with custom explanations. Use AI to generate user guides, API references, or developer documentation based on your actual code.

Installation

Using bash

The easiest way to install Context Generator is by using our installation script. This automatically downloads the latest version and sets it up for immediate use.

# Install to /usr/local/bin (will be added to PATH in most Linux distributions)
curl -sSL https://raw.githubusercontent.com/butschster/context-generator/main/download-latest.sh | sh

What the script does

• Detects the latest version
• Downloads the PHAR file from GitHub releases
• Installs it to your bin directory (default: /usr/local/bin)
• Makes it executable

After installation, you can use Context Generator by simply running:

context-generator generate

Using PHAR file

The simplest way to use Context Generator is by downloading the ready-to-use PHAR file directly. No Composer or dependency installation required!

Download and make executable:

wget https://github.com/butschster/context-generator/releases/download/1.0.2/context-generator.phar
chmod +x context-generator.phar

Move it to a convenient location for easy access:

# Option 1: Move to current project
mv context-generator.phar ./context-generator

# Option 2: Move to a directory in your PATH (for system-wide access)
mv context-generator.phar /usr/local/bin/context-generator

This approach is perfect for quickly trying out the tool or for environments where Composer isn't available.

Using Composer

In some cases you may want to use Context Generator as a library in your PHP project to provide custom functionality or to integrate it into your existing codebase, provide more modifiers or custom sources.

In this case you can install it via Composer:

composer require butschster/context-generator --dev

Requirements

• PHP 8.2 or higher
• PSR-18 HTTP client (for URL sources)
• Symfony Finder component

Usage

Basic Usage

Create a configuration file (default: context.php or context.json) in your project root:

<?php

use Butschster\ContextGenerator\Document;
use Butschster\ContextGenerator\DocumentRegistry;
use Butschster\ContextGenerator\Source\FileSource;
use Butschster\ContextGenerator\Source\TextSource;
use Butschster\ContextGenerator\Source\UrlSource;
use Butschster\ContextGenerator\Source\GithubSource;

return (new DocumentRegistry())
    ->register(
        Document::create(
            description: 'API Documentation',
            outputPath: 'docs/api.md',
        )
        ->addSource(
            new FileSource(
                sourcePaths: __DIR__ . '/src/Api',
                description: 'API Source Files',
                filePattern: '*.php',
                excludePatterns: ['tests', 'vendor'],
                showTreeView: true,
                modifiers: ['php-signature'],
            ),
            new TextSource(
                content: "# API Documentation\n\nThis document contains the API source code.",
                description: 'API Documentation Header',
            ),
        ),
    )
    ->register(
        Document::create(
            description: 'Website Content',
            outputPath: 'docs/website.md',
        )
        ->addSource(
            new UrlSource(
                urls: ['https://example.com/docs'],
                description: 'Documentation Website',
                selector: '.main-content',
            ),
        ),
    )
    ->register(
        Document::create(
            description: 'GitHub Repository',
            outputPath: 'docs/github-repo.md',
        )
        ->addSource(
            new GithubSource(
                repository: 'owner/repo',
                sourcePaths: 'src',
                branch: 'main',
                description: 'Repository Source Files',
                filePattern: '*.php',
                excludePatterns: ['tests', 'vendor'],
                showTreeView: true,
                githubToken: '${GITHUB_TOKEN}', // Optional: GitHub token for private repositories or rate limits
                modifiers: ['php-signature'],
            ),
        ),
    );

or

{
  "documents": [
    {
      "description": "API Documentation",
      "outputPath": "docs/api.md",
      "sources": [
        {
          "type": "file",
          "description": "API Source Files",
          "sourcePaths": [
            "src/Api"
          ],
          "filePattern": "*.php",
          "excludePatterns": [
            "tests",
            "vendor"
          ],
          "showTreeView": true,
          "modifiers": [
            "php-signature"
          ]
        },
        {
          "type": "text",
          "description": "API Documentation Header",
          "content": "# API Documentation\n\nThis document contains the API source code."
        }
      ]
    },
    {
      "description": "Website Content",
      "outputPath": "docs/website.md",
      "sources": [
        {
          "type": "url",
          "description": "Documentation Website",
          "urls": [
            "https://example.com/docs"
          ],
          "selector": ".main-content"
        }
      ]
    },
    {
      "description": "GitHub Repository",
      "outputPath": "docs/github-repo.md",
      "sources": [
        {
          "type": "github",
          "description": "Repository Source Files",
          "repository": "owner/repo",
          "sourcePaths": [
            "src"
          ],
          "branch": "main",
          "filePattern": "*.php",
          "excludePatterns": [
            "tests",
            "vendor"
          ],
          "showTreeView": true,
          "modifiers": [
            "php-signature"
          ]
        }
      ]
    }
  ]
}

Note: We provide json-schema.json for JSON configuration validation. You can use it to validate your JSON configuration file or for autocompletion in your IDE.

Then run the command:

./vendor/bin/context-generator generate

Source Types

FileSource

The Butschster\ContextGenerator\Source\FileSource allows you to include content from files and directories:

use Butschster\ContextGenerator\Source\FileSource;

new FileSource(
    sourcePaths: __DIR__ . '/src',        // Path to directory or file
    description: 'Source Code',           // Optional description
    filePattern: '*.php',                 // File pattern to match (default: *.php)
    excludePatterns: ['tests', 'vendor'], // Patterns to exclude
    showTreeView: true,                    // Whether to show tree view (default: true)
    modifiers: ['php-signature'],         // Optional content modifiers to apply
);

GithubSource

The Butschster\ContextGenerator\Source\GithubSource allows you to include content directly from a GitHub repository:

use Butschster\ContextGenerator\Source\GithubSource;

new GithubSource(
    repository: 'owner/repo',             // GitHub repository in format "owner/repo"
    sourcePaths: 'src',                   // Path(s) within the repository (string or array)
    branch: 'main',                       // Branch or tag to fetch from (default: main)
    description: 'Repository files',      // Optional description
    filePattern: '*.php',                 // Pattern to match files (default: *.php)
    excludePatterns: ['tests', 'vendor'], // Patterns to exclude
    showTreeView: true,                   // Whether to show directory tree (default: true)
    githubToken: '${GITHUB_TOKEN}',       // GitHub API token for private repos (can use env vars)
    modifiers: ['php-signature'],         // Optional content modifiers to apply
);

UrlSource

The Butschster\ContextGenerator\Source\UrlSource allows you to fetch content from websites and extract specific sections using CSS selectors. It also cleans the HTML content to remove unnecessary elements and converts into markdown format.

use Butschster\ContextGenerator\Source\UrlSource;

new UrlSource(
    urls: ['https://example.com/docs'],  // URLs to fetch
    description: 'Documentation',        // Optional description
    selector: '.main-content'            // Optional CSS selector to extract specific content
);

TextSource

The Butschster\ContextGenerator\Source\TextSource allows you to include plain text content like headers or notes or additional instructions.

use Butschster\ContextGenerator\Source\TextSource;

new TextSource(
    content: <<<TEXT
        # Project Goals
        This project aims to provide a robust solution for...
        
        ## Key Features
        - Feature 1: Description
        - Feature 2: Description
        TEXT,
    description: 'Project goals and key features',
);

Content Modifiers

Content modifiers allow you to transform the source content before it's included in the document. Currently, Context Generator includes the following modifiers:

Php files Signature Modifier

The php-signature modifier extracts PHP class signatures without implementation details. This is useful for providing API documentation without cluttering the context with implementation details.

The modifier will transform:

class Example 
{
    private $property;
    
    public function doSomething($param)
    {
        // Implementation...
        return $result;
    }
    
    private function helperMethod()
    {
        // Implementation...
    }
}

Into:

class Example 
{
    public function doSomething($param) 
    {
        /* ... */
    }
}

License

This project is licensed under the MIT License.