Overview

Secure JavaScript execution environment with defense-in-depth architecture for running untrusted and LLM-generated code safely

Enclave is a secure execution environment for running untrusted JavaScript code. It provides a defense-in-depth security model that combines AST validation (via ast-guard), code transformation, and runtime sandboxing to safely execute model-generated code.

AST Validation

Block dangerous constructs before execution using ast-guard’s AgentScript preset

Code Transformation

Automatically transform code for safe execution with proxied functions and loop limits

Runtime Sandboxing

Execute in isolated Node.js vm context with controlled globals and resource limits

When to Use Enclave

Enclave is designed for scenarios where you need to execute JavaScript code from untrusted sources:

• LLM-generated code - Execute code written by AI models safely
• User-provided scripts - Run user scripts in a controlled environment
• Plugin/extension systems - Allow third-party code to run securely
• Workflow automation - Execute orchestration logic with tool access

Installation

npm install @enclave-vm/core

Quick Start

import { Enclave } from '@enclave-vm/core';

// Create an enclave with a tool handler
const enclave = new Enclave({
  timeout: 5000, // 5 second timeout
  maxToolCalls: 50, // Max 50 tool calls
  maxIterations: 10000, // Max 10K loop iterations
  toolHandler: async (toolName, args) => {
    // Handle tool calls from the script
    console.log(`Tool called: ${toolName}`, args);
    return { result: 'data' };
  },
});

// Execute AgentScript code
const code = `
  const users = await callTool('users:list', { limit: 10 });
  const filtered = users.filter(u => u.active);
  return filtered.length;
`;

const result = await enclave.run(code);

if (result.success) {
  console.log('Result:', result.value);
  console.log('Stats:', result.stats);
} else {
  console.error('Error:', result.error);
}

// Clean up
enclave.dispose();

Execution Results

Enclave returns a structured result with success/error status and execution stats:

interface ExecutionResult<T> {
  success: boolean;
  value?: T;              // Result value (if success)
  error?: {               // Error details (if failed)
    name: string;
    message: string;
    code: string;
    stack?: string;
  };
  stats: {
    duration: number;      // Execution time in ms
    toolCallCount: number; // Number of tool calls made
    iterationCount: number; // Number of loop iterations
  };
}

Error Codes

Code	Meaning	Action
VALIDATION_ERROR	AST validation failed	Fix the code - blocked construct used
EXECUTION_ERROR	Runtime error in script	Fix script logic
TIMEOUT	Execution exceeded timeout	Optimize or increase timeout
TOOL_ERROR	Tool call failed	Check tool input/availability
MEMORY_LIMIT_EXCEEDED	Memory limit exceeded	Reduce memory usage or increase limit

Related

• Security Levels - Pre-configured security profiles
• Tool System - Integrating tools with enclave
• Configuration - All configuration options
• ast-guard - AST validation library