omc-mcp-extension

omc-mcp-extension

MCP server extension for oh-my-claudecode

A lightweight extension plugin that adds additional MCP servers to oh-my-claudecode's powerful skill/hook/agent system.

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Features

MCP Server	Purpose	Required
Context7	Official library documentation lookup	npx
Serena	Semantic code analysis + session memory persistence	uvx
Sequential	Structured multi-step reasoning (30-50% token savings)	npx
Morphllm	Pattern-based bulk code editing	npx + API Key

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Installation

Prerequisites

# Node.js 18+ required
node --version   # v18.0.0 or higher

# uvx required (for Serena)
pip install uv   # or: pipx install uv
which uvx        # verify installation

# jq required (for setup skill)
brew install jq  # macOS

Install

# 1. Install OMC first (skip if already installed)
claude plugin marketplace add https://github.com/Yeachan-Heo/oh-my-claudecode
claude plugin install oh-my-claudecode@omc

# 2. Install this extension plugin
claude plugin marketplace add https://github.com/chlee1001/omc-mcp-extension
claude plugin install omc-mcp-extension@omc-mcp-extension

Post-Installation Setup (Required)

Run the setup skill to complete installation:

/omc-mcp-extension:setup

This will:

• ✅ Backup ~/.claude.json and ~/.claude/CLAUDE.md
• ✅ Update ~/.claude.json mcpServers (skips duplicates)
• ✅ Copy MCP behavior guides to ~/.claude/
• ✅ Add @import references to ~/.claude/CLAUDE.md
• ✅ Configure Morphllm with API key directly in mcpServers

⚠️ Restart Claude Code after setup to apply MCP changes!

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Skills

Skill	Description	Usage
setup	Complete MCP setup with backups	/omc-mcp-extension:setup

What Setup Does

~/.claude.json             # mcpServers updated (skips duplicates)
~/.claude/
├── CLAUDE.md              # Updated with @import references
├── MCP_Context7.md        # Behavior guide (copied)
├── MCP_Serena.md          # Behavior guide (copied)
├── MCP_Sequential.md      # Behavior guide (copied)
├── MCP_Morphllm.md        # Behavior guide (copied)
└── backups/
    ├── claude.json.backup_[timestamp]
    └── CLAUDE.md.backup_[timestamp]

~/.claude.json mcpServers:

{
  "mcpServers": {
    "context7": { "command": "npx", "args": ["-y", "@upstash/context7-mcp"] },
    "serena": { "command": "uvx", "args": [...] },
    "sequential-thinking": { "command": "npx", "args": [...] },
    "morphllm-fast-apply": {
      "command": "npx",
      "args": ["@morph-llm/morph-fast-apply"],
      "env": { "MORPH_API_KEY": "your-key-here" }
    }
  }
}

CLAUDE.md additions:

<!-- OMC-MCP-EXT:START -->
# MCP Server Guides (omc-mcp-extension)

@MCP_Context7.md
@MCP_Serena.md
@MCP_Sequential.md
@MCP_Morphllm.md
<!-- OMC-MCP-EXT:END -->

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How It Works

Architecture

┌─────────────────────────────────────────────────────────────┐
│                    Claude Code Runtime                       │
├─────────────────────────────────────────────────────────────┤
│                                                              │
│  MCP Servers (in ~/.claude/settings.json)                   │
│  ├── OMC Built-in                                           │
│  │   ├─ "t" (OMC Bridge) - LSP, AST tools (18 tools)       │
│  │   └─ context7 - Official docs lookup (built-in)         │
│  │                                                          │
│  └── omc-mcp-extension (added by setup skill)              │
│      ├─ serena             → Semantic analysis + memory     │
│      ├─ sequential-thinking → Structured reasoning          │
│      └─ morphllm-fast-apply → Bulk editing                  │
│                                                              │
└─────────────────────────────────────────────────────────────┘

Workflow Example

User: "autopilot: refactor the authentication module"
         │
         ▼
OMC Hook: keyword-detector
  → Detects "autopilot" → Injects skill
         │
         ▼
OMC Agents + MCP Tools Collaboration
  Analyst  → mcp__t__lsp_diagnostics (code analysis)
  Architect → mcp__sequential-thinking__* (structured reasoning)
  Executor → mcp__serena__find_symbol (navigation)
           → mcp__morphllm-fast-apply__edit_file (bulk editing)

---

MCP Selection Guide

When you need...	Use	Example
Official library docs	Context7 (OMC built-in)	"How to use React useEffect"
Symbol rename/find refs	Serena	"Rename getUserData to fetchUser"
Complex multi-step analysis	Sequential	"Why is this API slow?"
Pattern-based bulk edits	Morphllm	"Convert all var to const"
Simple tasks	Native Claude	"Explain this function"

Collaboration Patterns