Using Fellow in VS Code¶

Fellow works seamlessly with the Claude Code VS Code extension, providing the same powerful semantic knowledge extraction and automatic context enrichment in a visual IDE environment.

Quick Start¶

1. Install Claude Code CLI¶

Install Claude Code CLI first:

# Using Homebrew
brew install claude

# Verify installation
claude --version

# Using installer script
curl -fsSL https://code.claude.com/install.sh | sh

# Verify installation
claude --version

# Using winget
winget install Anthropic.ClaudeCode

# Verify installation
claude --version

Or download from: https://code.claude.com

2. Install VS Code Extension¶

After installing the CLI, install the VS Code extension:

From VS Code: 1. Open Extensions view (Cmd+Shift+X or Ctrl+Shift+X) 2. Search for "Claude Code" 3. Click "Install"

Or from command line:

code --install-extension anthropic.claude-code

3. Install Fellow Plugin¶

Now install Fellow using the Claude Code CLI (from step 1):

# Clone Fellow repository
git clone https://github.com/jingnanzhou/fellow.git
cd fellow

# Add as local marketplace
claude plugin marketplace add ./

# Install from local marketplace
claude plugin  install fellow@local_marketplace

# Verify installation
claude plugin list

4. Start Using Fellow¶

Open the Claude Code panel in VS Code and start coding:

# Build knowledge base for your project
/build-kb

# Start coding with automatic enrichment
"Add validation to the user registration endpoint"

Fellow automatically enriches your requests with context, just like in the CLI!

How It Works¶

Shared Configuration¶

The VS Code extension and CLI share the same plugin system:

~/.claude/
├── settings.json               # Shared settings
└── cache/
    └── plugins/
        └── fellow/            # Plugin files

your-project/
├── .fellow-data/              # Knowledge base
│   ├── semantic/              # Same location as CLI
│   └── logs/
└── .claude/
    └── settings.json          # Project settings

Key Points: - Plugins installed via CLI are automatically available in VS Code - Knowledge bases work identically in both environments - Settings from .claude/settings.json apply to both - Hooks work the same way (automatic enrichment)

Fellow Features in VS Code¶

All Fellow features work in VS Code:

Using Fellow Commands¶

Build Knowledge Base¶

Build or update your knowledge base:

# First time - full extraction (2-5 minutes)
/build-kb

# After code changes - incremental update (10-20 seconds)
/build-kb --update

# Force full rebuild
/build-kb --full

Output in VS Code: - Progress shown in Claude panel - Extraction results displayed - Knowledge base created in .fellow-data/semantic/

Automatic Enrichment¶

Fellow automatically enriches coding requests:

# Just type your request naturally:
"Add caching to the tool listing API"

# Fellow automatically:
# 1. Detects this is a coding request
# 2. Loads relevant knowledge from KB
# 3. Enriches with entities, workflows, constraints
# 4. Passes to Claude for implementation

You'll see:

📋 Context from Knowledge Base

**Relevant Entities:**
- CacheService (class): Redis-based caching
- ToolRepository (class): Data access layer

**Architectural Guardrails:**
- [Performance] Use Redis for caching
- [Architecture] Set TTL to 60 seconds
- [Pattern] Use cache-aside pattern

[Implementation follows...]

Manual Enrichment¶

Force enrichment even for ambiguous requests:

/fellow Add error handling to the API

Manage Hooks¶

Control automatic enrichment:

# Check status
/toggle-hooks status

# Disable temporarily
/toggle-hooks off

# Re-enable
/toggle-hooks on

Visual Benefits of VS Code¶

1. Inline Diffs¶

CLI: Text-based diffs in terminal VS Code: Visual inline diffs with highlighting

Benefits: - See changes in context of your file - Click to accept/reject changes - Multiple files shown in tabs - Syntax highlighting preserved

2. File Selection¶

VS Code Advantage: @-mention files from editor

# In CLI:
/fellow Add auth to src/api/users.py

# In VS Code:
"Add auth to this endpoint"
# (with users.py file selected or @-mentioned)

3. Integrated Workflow¶

No context switching: - Edit code in VS Code - Ask Fellow for help in panel - Review diffs inline - Accept changes with click - Continue coding

vs CLI workflow: - Edit in editor - Switch to terminal - Review text diffs - Switch back to editor - Apply changes manually

4. Multiple Conversations¶

VS Code allows: - Multiple Claude conversations in tabs - Keep context of different tasks - Switch between conversations easily

Configuration¶

Project-Level Settings¶

Create .claude/settings.json in your project:

{
  "enabledPlugins": {
    "fellow@user": true
  },
  "pluginSettings": {
    "fellow": {
      "autoUpdate": true,
      "logLevel": "info"
    }
  }
}

Customize Fellow Behavior¶

Edit Fellow's hook configuration:

Location: ~/.claude/cache/plugins/fellow/.claude-plugin/hooks.json

{
  "hooks": [{
    "name": "fellow-context-enrichment",
    "enabled": true,
    "config": {
      "min_confidence": 0.7,
      "silent_mode": false,
      "logging_enabled": false
    }
  }]
}

Recommended settings for VS Code:

{
  "min_confidence": 0.7,
  "silent_mode": false,
  "logging_enabled": true
}

{
  "min_confidence": 0.7,
  "silent_mode": false,
  "logging_enabled": false
}

{
  "min_confidence": 0.9,
  "silent_mode": false,
  "logging_enabled": false
}

Enable Logging¶

To see what context Fellow is adding:

export FELLOW_LOGGING=1

Logs appear in:

.fellow-data/logs/
├── enrichment_2026-01-05.jsonl    # Machine-readable
└── enrichment_2026-01-05.log      # Human-readable

Workflow Examples¶

Example 1: New Feature with Visual Review¶

Scenario: Add a new API endpoint

1. Build knowledge base:

   /build-kb
   

2. Request feature:

   "Add a POST endpoint for creating orders with items and payment info"
   

3. Review in VS Code:

4. Fellow enriches with Order entities, payment workflows, constraints
5. Claude generates code
6. See inline diffs with syntax highlighting
7. Click "Accept" on each change

8. Files updated automatically

9. Update knowledge base:

   /build-kb --update
   

Example 2: Refactoring with Context¶

Scenario: Refactor authentication logic

1. Select code in editor:

2. Highlight authentication code in auth.py

3. Request refactoring:

   "Refactor this to use the Strategy pattern"
   

4. Fellow provides context:

5. Loads existing auth patterns
6. Shows current architecture

7. Applies security constraints

8. Review changes:

9. Visual diff shows before/after
10. Accept changes with confidence

Example 3: Multi-Project Setup¶

Scenario: Working on multiple projects

# Project A
cd /workspace/api-service
/build-kb

# Work on Project A in VS Code
# Fellow uses api-service knowledge base

# Project B
cd /workspace/web-app
/build-kb

# Switch to Project B in VS Code
# Fellow automatically uses web-app knowledge base

Fellow automatically discovers the correct knowledge base based on your current workspace!

Keyboard Shortcuts¶

Useful VS Code shortcuts for Claude + Fellow:

Troubleshooting¶

Issue: Fellow commands not available¶

Solution:

1. Verify Fellow is installed:

   /plugin list
   

2. Restart VS Code:

3. Close and reopen VS Code

4. Plugins should load automatically

5. Check VS Code extension is enabled:

6. Extensions view → "Claude Code" → Ensure enabled

Issue: Knowledge base not found in VS Code¶

Solution:

Make sure you're in the correct workspace:

1. Check current directory in VS Code:

2. Terminal → pwd (macOS/Linux) or cd (Windows)

3. Build KB for this workspace:

   /build-kb
   

4. Verify KB was created:

   ls .fellow-data/semantic/
   

Issue: Hooks not working in VS Code¶

Solution:

1. Check hook status:

   /toggle-hooks status
   

2. Verify hooks are enabled:

   cat ~/.claude/cache/plugins/fellow/.claude-plugin/hooks.json
   # "enabled": true
   

3. Enable logging to debug:

   export FELLOW_LOGGING=1
   

4. Try explicit command:

   /fellow Add feature X
   

Issue: Slow first-time extraction¶

Expected behavior:

• First extraction: 2-5 minutes (same as CLI)
• Incremental updates: 10-20 seconds

This is normal! Grab a coffee while Fellow analyzes your codebase.

Best Practices for VS Code¶

1. Use Visual Diffs¶

Take advantage of VS Code's visual diff view: - Review each change carefully - See changes in context - Accept/reject selectively

2. Organize Conversations¶

Keep conversations focused: - One conversation per feature/task - Use tabs for parallel work - Archive completed conversations

3. Leverage @-mentions¶

Use @-mentions for precise context:

"Add validation to @src/api/users.py on lines 45-67"

4. Update KB Regularly¶

After significant changes:

/build-kb --update

Keep Fellow's knowledge current for best results.

5. Use Logging During Learning¶

Enable logging while learning Fellow:

export FELLOW_LOGGING=1

See what context is being added, then disable once confident.

Comparison: CLI vs VS Code¶

When to Use CLI¶

Best for: - Quick terminal-based workflows - Scripting and automation - Server/remote environments - Preference for keyboard-only interaction

When to Use VS Code Extension¶

Best for: - Visual code review - IDE-integrated workflow - Multi-file changes - Learning Fellow (visual feedback) - Teams familiar with VS Code

Use Both!¶

Many developers use both: - VS Code for feature development (visual diffs) - CLI for quick updates and scripts - Conversations and knowledge bases are shared!

Next Steps¶

Now that you know how to use Fellow in VS Code:

1. Quick Start Guide - Build your first knowledge base
2. Commands Overview - Learn all Fellow commands
3. Cheat Sheet - Quick reference
4. Best Practices - Optimize your workflow

Resources¶

• Claude Code VS Code Extension: VS Code Marketplace
• VS Code Extension Docs: https://code.claude.com/docs/en/vs-code.md
• Fellow Documentation: https://jingnanzhou.github.io/fellow/
• GitHub: https://github.com/jingnanzhou/fellow

Fellow + VS Code = Visual AI coding with your architecture