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Documentation Index

Fetch the complete documentation index at: https://docs.agentfront.dev/llms.txt

Use this file to discover all available pages before exploring further.

The tool system allows scripts to interact with external systems through controlled callTool() invocations. Tools are the primary way for sandboxed code to perform actions and retrieve data.

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Basic Tool Handler

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

const enclave = new Enclave({
  timeout: 10000,
  toolHandler: async (toolName, args) => {
    console.log(`Tool called: ${toolName}`, args);

    switch (toolName) {
      case 'users:list':
        return { items: [{ id: 1, name: 'Alice' }] };
      case 'users:get':
        return { id: args.id, name: 'Alice' };
      default:
        throw new Error(`Unknown tool: ${toolName}`);
    }
  },
});

const result = await enclave.run(`
  const users = await callTool('users:list', {});
  return users.items.length;
`);

​
Tool Handler Signature

type ToolHandler = (
  toolName: string,  // Tool identifier (e.g., 'users:list')
  args: unknown      // Arguments passed from the script
) => Promise<unknown>;

​
Integrating with a Tool Registry

Connect enclave to your existing tool system: 
import { Enclave } from '@enclave-vm/core';
import { ToolRegistry } from './tools';

const enclave = new Enclave({
  timeout: 10000,
  toolHandler: async (toolName, args) => {
    // Look up tool in registry
    const tool = ToolRegistry.get(toolName);
    if (!tool) {
      throw new Error(`Unknown tool: ${toolName}`);
    }

    // Validate input schema
    const validatedArgs = tool.inputSchema.parse(args);

    // Execute with your pipeline (auth, logging, etc.)
    return tool.execute(validatedArgs);
  },
});

​
Tool Call Limits

Prevent runaway scripts with tool call limits: 
const enclave = new Enclave({
  maxToolCalls: 50, // Maximum tool calls per execution
  toolHandler: async (name, args) => { /* ... */ },
});
When the limit is exceeded, execution fails with error code MAX_TOOL_CALLS.

​
Custom Globals

Provide custom globals for scripts to access: 
const enclave = new Enclave({
  toolHandler: async (name, args) => { /* ... */ },
  globals: {
    // Custom read-only context
    context: {
      userId: 'user-123',
      tenantId: 'tenant-456',
    },
    // Custom utility function
    formatDate: (date: Date) => date.toISOString(),
  },
});

const code = `
  const userId = context.userId;
  const timestamp = formatDate(new Date());
  return { userId, timestamp };
`;

const result = await enclave.run(code);

​
One-Shot Execution

For simple cases without a persistent enclave instance: 
import { runAgentScript } from '@enclave-vm/core';

const result = await runAgentScript(`
  return Math.max(1, 2, 3);
`, {
  timeout: 1000,
});

console.log(result.value); // 3

​
Tool Error Handling

Handle tool errors gracefully: 
const enclave = new Enclave({
  toolHandler: async (name, args) => {
    try {
      return await executeToolSafely(name, args);
    } catch (error) {
      // Return structured error that script can handle
      return {
        error: true,
        code: error.code || 'TOOL_ERROR',
        message: error.message,
      };
    }
  },
});

const code = `
  const result = await callTool('risky:operation', {});
  if (result.error) {
    return { success: false, reason: result.message };
  }
  return { success: true, data: result };
`;

​
Securing Tool Access

Limit which tools are available based on context: 
const enclave = new Enclave({
  toolHandler: async (name, args) => {
    // Allowlist of permitted tools
    const allowedTools = ['users:list', 'users:get', 'data:read'];

    if (!allowedTools.includes(name)) {
      throw new Error(`Tool not allowed: ${name}`);
    }

    return ToolRegistry.execute(name, args);
  },
});

​
Async Tool Calls

Tools are always async, allowing for external API calls: 
const enclave = new Enclave({
  toolHandler: async (name, args) => {
    if (name === 'api:fetch') {
      const response = await fetch(args.url);
      return response.json();
    }
    // ...
  },
});

​
Tool Call Statistics

Track tool usage in execution stats: 
const result = await enclave.run(code);

console.log('Tool calls made:', result.stats.toolCallCount);
console.log('Execution time:', result.stats.duration);