Platform Support

Runtime compatibility and platform-specific considerations

Composio TypeScript SDK supports multiple JavaScript runtimes with varying levels of compatibility.

Supported Platforms

Node.js ✅

Fully Supported - All features work out of the box.

node >= 18.0.0

import { Composio } from '@composio/core';

const composio = new Composio({ apiKey: 'your-key' });

Features:

• ✅ All API methods
• ✅ File operations
• ✅ Triggers (Pusher)
• ✅ MCP servers
• ✅ Tool Router
• ✅ Custom tools

Bun ✅

Fully Supported - Optimized for Bun runtime.

bun >= 1.0.0

import { Composio } from '@composio/core';

const composio = new Composio({ apiKey: 'your-key' });

Features:

• ✅ All API methods
• ✅ File operations (Bun.file)
• ✅ Triggers
• ✅ Faster performance than Node.js

Deno ⚠️

Partially Supported - Requires permissions.

// Import from npm:
import { Composio } from 'npm:@composio/core';

const composio = new Composio({ apiKey: 'your-key' });

Required Permissions:

deno run --allow-net --allow-read --allow-write --allow-env your-script.ts

Features:

• ✅ All API methods
• ⚠️ File operations (with —allow-read/—allow-write)
• ✅ Triggers
• ⚠️ May require additional permissions

Cloudflare Workers ⚠️

Partially Supported - No filesystem access.

import { Composio } from '@composio/core';

export default {
  async fetch(request: Request, env: Env, ctx: ExecutionContext) {
    const composio = new Composio({ apiKey: env.COMPOSIO_API_KEY });
    
    const result = await composio.tools.execute('GITHUB_GET_REPOS', {
      userId: 'default',
      arguments: { owner: 'composio' }
    });
    
    // Important: Flush telemetry before worker terminates
    ctx.waitUntil(composio.flush());
    
    return new Response(JSON.stringify(result));
  }
};

Features:

• ✅ Tool execution
• ✅ Connected accounts
• ✅ Auth configs
• ❌ File operations (no fs)
• ⚠️ Triggers (requires Durable Objects)
• ⚠️ Must call flush() before termination

Limitations:

• No filesystem access
• No persistent storage
• Must manually flush telemetry
• Limited to 50ms CPU time

Browser ⚠️

Limited Support - Use for client-side auth flows only.

import { Composio } from '@composio/core';

const composio = new Composio({ apiKey: 'your-public-key' });

// ⚠️ Don't expose your API key in browser!
// Use backend proxy for sensitive operations

const connectionRequest = await composio.connectedAccounts.link(
  'user_123',
  'auth_config_abc'
);

window.location.href = connectionRequest.redirectUrl;

Features:

• ⚠️ Limited to public APIs
• ✅ Connection flows
• ❌ Tool execution (use backend)
• ❌ File operations
• ❌ Triggers

Security Warning:

Never expose your Composio API key in browser code. Use a backend proxy for sensitive operations.

Feature Compatibility Matrix

Feature	Node.js	Bun	Deno	Cloudflare	Browser
Tools API	✅	✅	✅	✅	⚠️
Toolkits	✅	✅	✅	✅	✅
Connected Accounts	✅	✅	✅	✅	⚠️
Auth Configs	✅	✅	✅	✅	⚠️
Triggers	✅	✅	✅	⚠️	❌
File Operations	✅	✅	⚠️	❌	❌
Custom Tools	✅	✅	✅	✅	❌
MCP Servers	✅	✅	⚠️	❌	❌
Tool Router	✅	✅	✅	⚠️	❌

Platform-Specific Code

Cloudflare Workers

import { Composio } from '@composio/core';

export default {
  async fetch(request: Request, env: Env, ctx: ExecutionContext) {
    const composio = new Composio({
      apiKey: env.COMPOSIO_API_KEY,
      // Disable file operations
      autoUploadDownloadFiles: false
    });

    try {
      const tools = await composio.tools.get('default', {
        toolkits: ['github']
      });

      return new Response(JSON.stringify(tools));
    } finally {
      // Always flush telemetry
      ctx.waitUntil(composio.flush());
    }
  }
};

Deno

// deno.json
{
  "imports": {
    "@composio/core": "npm:@composio/core"
  },
  "tasks": {
    "dev": "deno run --allow-all main.ts"
  }
}

// main.ts
import { Composio } from '@composio/core';

const composio = new Composio({
  apiKey: Deno.env.get('COMPOSIO_API_KEY')!
});

const tools = await composio.tools.get('default', {
  toolkits: ['github']
});

console.log(tools);

Testing

Run platform-specific tests:

# Node.js
pnpm test

# Node.js CJS/ESM compatibility
pnpm test:e2e:node

# Deno
pnpm test:e2e:deno

# Cloudflare Workers
pnpm test:e2e:cloudflare

Best Practices

1. Platform Detection: Check runtime before using platform-specific features
2. Graceful Degradation: Disable unsupported features
3. Error Handling: Handle platform-specific errors
4. Testing: Test on target platform
5. Documentation: Document platform requirements

Troubleshooting

”fs module not found” in Cloudflare Workers

// Disable file operations
const composio = new Composio({
  apiKey: 'your-key',
  autoUploadDownloadFiles: false
});

”Telemetry not flushing” in Workers

// Always call flush()
ctx.waitUntil(composio.flush());

Permission errors in Deno

# Grant required permissions
deno run --allow-net --allow-env --allow-read --allow-write your-script.ts

Next Steps

Installation

Get started

Files API

File operations

Composio Class

Main SDK reference

Examples

View examples