fellow

Overview

Fellow helps Claude understand your codebase by extracting three types of knowledge:

1. Factual Knowledge - What entities, models, and data structures exist
2. Procedural Knowledge - How workflows and execution flows work
3. Conceptual Knowledge - What the overall architecture and design patterns are

This knowledge enables intelligent coding assistance with:

• Context-aware code suggestions
• Architectural boundary enforcement
• Constraint checking
• Pattern-consistent implementations

🚀 AST-Enhanced Extraction (Default)

Fellow features AST-enhanced extraction enabled by default for massive performance improvements:

• 90% token reduction = 10x lower costs
• 10x faster extraction = seconds instead of minutes
• Multi-language support = Python, JavaScript/TypeScript, Java + fallback for all others
• Zero dependencies = Pure Python stdlib
• 100% compatible = Works with any codebase

It's automatic - just run:

/build-kb  # AST-enhanced by default - 90% faster, 90% cheaper!

Use --no-ast only if you need traditional extraction for debugging.

See Multi-Language Support for details.

🔬 Call Graph Analysis (Phase 2 - Experimental)

NEW: Phase 2 adds call graph-enhanced workflow extraction for even better code understanding:

• Automatic workflow identification - Traces execution flows from entry points
• 75% token reduction for workflow understanding vs traditional method
• 70% faster procedural knowledge extraction
• Multi-language support - Python (100%), JavaScript/TypeScript (90%), Java (90%)
• Dependency mapping - Identifies external services and components

Enable with --callgraph flag:

/build-kb --callgraph  # Best quality workflow extraction

How it works: Extracts call graphs → Identifies entry points → Traces execution flows → Understands semantic meaning

See Phase 2 Documentation for details.

Installation

# Step 1: Add as local marketplace
claude plugin marketplace add https://github.com/jingnanzhou/fellow.git

# Step 2: Install from local marketplace
claude plugin install fellow@local_marketplace

# Step 3: Verify installation
claude plugin list

Works in both CLI and VS Code! Fellow automatically works with the Claude Code VS Code extension.

Removing the Plugin

To uninstall Fellow:

# Step 1: Uninstall the plugin
claude plugin uninstall fellow@local_marketplace

# Step 2: Remove the marketplace
claude plugin marketplace remove local_marketplace

See INSTALLATION.md for comprehensive installation guide.

Requirements

• Claude Code CLI or VS Code Extension - Fellow works with both!
• Python 3.8+ - For knowledge extraction (standard library only, no packages required)
• Git - Optional, for cloning from source

VS Code Users

Fellow works seamlessly with the Claude Code VS Code extension:

1. Install Claude Code extension in VS Code
2. Install Fellow: /plugin install fellow
3. All Fellow features work identically with visual benefits!

See VS Code Integration Guide for details.

Quick Reference

After installation:

• Commands Available: /build-kb, /fellow, /toggle-hooks
• Hooks Status: Use /toggle-hooks status to check
• Cheat Sheet: See docs/CHEAT_SHEET.md for all commands

Quick Start

# Option 1: Build knowledge base first (recommended)
# 🚀 AST-enhanced by default - 90% faster!
/build-kb

# Option 2: Start coding immediately (auto-build)
# Fellow will offer to build KB automatically when needed!
"Add authentication to the user endpoint"

# Check if automatic enrichment is enabled (default: on)
/toggle-hooks status

# Start coding naturally - context is automatically enriched!
"Add validation to the registration form"

# Optional: Use manual enrichment with /fellow
/fellow Add caching to the API

# Optional: Update KB after code changes (incremental, fast with AST)
/build-kb --update

✨ New: Auto-Build Feature

If you forget to build the knowledge base, Fellow will:

• Detect it's missing when you make a coding request
• Inform you it will take 2-5 minutes
• Offer to build it automatically
• Then proceed with your request!