JIT Tool Synthesis v2

LLM-powered on-demand tool generation with human-in-the-loop approval and safe execution.

Overview

This system generates TypeScript tools dynamically using an LLM, requires human approval before execution, and runs them in a sandboxed environment.

Architecture

┌─────────────┐     ┌──────────────┐     ┌─────────────┐
│ Synthesizer │────▶│   Approval   │────▶│  Sandbox    │
│   (LLM)     │     │ (Human Gate) │     │ (Execution) │
└─────────────┘     └──────────────┘     └─────────────┘
       │                   │                    │
       ▼                   ▼                    ▼
  Generates TS        Waits for            Runs in
  tool code          human approval       isolated env

Components

File	Purpose
synthesizer.ts	Generates TypeScript code using OpenRouter LLM
approval.ts	Human-in-the-loop gate — requires approval before execution
sandbox.ts	Safe execution environment for generated code
registry.ts	Tool persistence and storage
server.ts	MCP server integration

Setup

# Install dependencies
npm install

# Copy environment template
cp .env.example .env

# Add your OpenRouter API key to .env
OPENROUTER_API_KEY=your_key_here

Usage

Start the MCP Server

npm run dev

Claude Desktop Integration

Import the config:

# Copy Claude Desktop config
cat claude-desktop-config.json

Add the JSON to your Claude Desktop settings under mcpServers.

CLI Commands

# Generate and approve a tool
npm run cli -- synthesize "Create a weather tool that fetches from wttr.in"

# List available tools
npm run cli -- list

# Execute a tool
npm run cli -- execute <tool-id>

Workflow

1. Request — User asks for a tool (e.g., "create a weather fetcher")
2. Synthesize — LLM generates TypeScript code
3. Approve — Human reviews and approves the code
4. Execute — Tool runs in sandboxed environment
5. Store — Approved tools persist in registry

Environment Variables

Variable	Description
OPENROUTER_API_KEY	API key for LLM tool generation
PORT	Server port (default: 3000)

Status

In Progress — MVP complete, end-to-end testing in progress.