> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/composiohq/composio/llms.txt
> Use this file to discover all available pages before exploring further.

# 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.

```bash theme={null}
node >= 18.0.0
```

```typescript theme={null}
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.

```bash theme={null}
bun >= 1.0.0
```

```typescript theme={null}
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.

```typescript theme={null}
// Import from npm:
import { Composio } from 'npm:@composio/core';

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

**Required Permissions:**

```bash theme={null}
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.

```typescript theme={null}
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.

```typescript theme={null}
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:**

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

## 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

```typescript theme={null}
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

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

```typescript theme={null}
// 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:

```bash theme={null}
# 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

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

### "Telemetry not flushing" in Workers

```typescript theme={null}
// Always call flush()
ctx.waitUntil(composio.flush());
```

### Permission errors in Deno

```bash theme={null}
# Grant required permissions
deno run --allow-net --allow-env --allow-read --allow-write your-script.ts
```

## Next Steps

<CardGroup cols={2}>
  <Card title="Installation" icon="download" href="/typescript/installation">
    Get started
  </Card>

  <Card title="Files API" icon="file" href="/typescript/advanced/files">
    File operations
  </Card>

  <Card title="Composio Class" icon="code" href="/typescript/api/composio">
    Main SDK reference
  </Card>

  <Card title="Examples" icon="code" href="https://github.com/composioHQ/composio/tree/master/typescript/examples">
    View examples
  </Card>
</CardGroup>