Nellie

What it does

Nellie acts as a high-performance local semantic code search server and context engineering layer that sits between developers and AI models. It provides agents with persistent memory by automatically retrieving relevant lessons, checkpoints, and structural code context before a prompt even reaches the model.

Tools

• search_hybrid: Vector similarity combined with knowledge graph expansion for rich context retrieval.
• search_code: Deep semantic search across indexed codebases.
• get_blast_radius: Analyzes code changes to identify affected symbols and necessary test files.
• query_structure: Explores function/class relationships including callers, callees, and definitions.
• add_lesson: Records learned patterns, mistakes, and preferences for future sessions.
• add_checkpoint: Saves working context for rapid recovery and state management.

Installation

Add to claude_desktop_config.json:

{
  "mcpServers": {
    "nellie": {
      "command": "nellie",
      "args": ["serve", "--host", "127.0.0.1", "--port", "8765"]
    }
  }
}

Supported hosts

• Claude Desktop
• Claude Code
• Cursor