# The Complete Guide to Claude Code V4
# Source: Reddit r/ClaudeAI - TheDecipherist
# URL: https://www.reddit.com/r/ClaudeAI/comments/1qquxle/the_complete_guide_to_claude_code_v4_the/

## V4: The January 2026 Revolution

Claude Code 2.1.x shipped 1,096+ commits in January alone. This isn't an incremental update - it's a fundamental shift in how Claude Code manages context, delegates work, and scales.

## What's New in V4:

**Part 9: MCP Tool Search**
- 85% context reduction with lazy loading

**Part 10: Custom Agents**
- Automatic delegation to specialists

**Part 11: Session Teleportation**
- Move sessions between devices

**Part 12: Background Tasks**
- Parallel agent execution

**Part 13: New Commands & Shortcuts**
- /config search, /stats filtering, custom keybindings

## TL;DR:

MCP Tool Search reduces context overhead by 85% (77K -> 8.7K tokens) by lazy-loading tools on-demand. Custom Agents let you create specialists that Claude invokes automatically - each with isolated context windows. Session Teleportation lets you move work between terminal and claude.ai/code seamlessly. Background Tasks enable parallel agent execution with Ctrl+B. And the new Setup hook automates repository initialization.

[Full extracted content available - see file for complete guide with all 13 parts]
