Best Practices & Type Definitions

A summary of recommended patterns and the main TypeScript types for quick reference.

Best Practices

1. Check connection before sending messages

if (client.state.isConnected) {
  client.sendUserTextMessage('Hello');
}

2. Handle errors

try {
  await client.connect(config);
} catch (err) {
  console.error('Connection failed', err);
}

3. Unsubscribe from events when needed

const off = client.on('message', handler);
off();

4. Disconnect on cleanup

window.addEventListener('beforeunload', () => {
  client.disconnect();
});

5. Keep UI responsive with stateChange

client.on('stateChange', updateUI);

---

Core Types:

import type {
  ConvaiClient,
  ConvaiConfig,
  ConvaiClientState,
  ChatMessage,
  IConvaiClient,
} from '@convai/web-sdk';

Control Interfaces:

import type {
  AudioControls,
  VideoControls,
  ScreenShareControls,
} from '@convai/web-sdk';

Lipsync Types:

import type {
  BlendshapeQueue,
  BlendshapeMapper,
  BlendshapeFormat,
  BlendshapeMappingConfig,
  BlendshapeNameMapping,
  OptimizedBlendshapeOutput,
} from '@convai/web-sdk';

Configuration Interface:

interface ConvaiConfig {
  apiKey: string;                    // Required: Your API key
  characterId: string;                // Required: Character ID
  endUserId?: string;                 // Optional: For memory & analytics
  url?: string;                       // Optional: Custom API endpoint
  enableVideo?: boolean;              // Enable video/screenshare (default: false)
  startWithVideoOn?: boolean;         // Start with camera on (default: false)
  startWithAudioOn?: boolean;         // Start with mic on (default: false)
  ttsEnabled?: boolean;               // Enable TTS (default: true)
  enableLipsync?: boolean;            // Enable blendshapes (default: false)
  blendshapeConfig?: {
    format?: 'arkit' | 'mha';         // Blendshape format (default: 'mha')
  };
  actionConfig?: {                    // Optional: Character actions
    actions: string[];
    characters: Array<{ name: string; bio: string }>;
    objects: Array<{ name: string; description: string }>;
    currentAttentionObject?: string;
  };
}

---

Client State Management

The ConvaiClientState interface provides complete visibility into the conversation state:

interface ConvaiClientState {
  isConnected: boolean;     // Connected to character
  isConnecting: boolean;    // Connection in progress
  isListening: boolean;     // Listening to user
  isThinking: boolean;      // Processing response
  isSpeaking: boolean;      // Character speaking
  agentState: string;       // Combined state
}

Agent State Values:

• 'disconnected' - Not connected
• 'connected' - Connected but idle
• 'listening' - Actively listening to user
• 'thinking' - Processing user input
• 'speaking' - Character is responding

Usage:

// React
const { state } = convaiClient;
if (state.isSpeaking) {
  console.log('Character is speaking');
}

// Vanilla
client.on('stateChange', (state) => {
  console.log('State:', state.agentState);
});

---

Event System

The SDK uses an event-driven architecture for state changes and messages:

Available Events:

Event	Parameters	Description
stateChange	(state: ConvaiClientState)	Connection/activity state changed
message	(message: ChatMessage)	New message received
messagesChange	(messages: ChatMessage[])	Message history updated
connect	()	Successfully connected
disconnect	()	Disconnected from character
error	(error: Error)	Error occurred
botReady	()	Bot is ready to receive messages
userTranscriptionChange	(transcription: string)	User speech transcription updated

Usage:

// Subscribe to events
const unsubscribe = client.on('stateChange', (state) => {
  console.log('State changed:', state);
});

// Unsubscribe
unsubscribe();

// Or manually
client.off('stateChange', callback);