Getting started
Rules Engine Widgets
Universal Voice Agent
8 min
purpose the universal voice agent node enables conversational ai powered voice interactions within your automation workflows it connects to popular voice ai providers like vapi, retell ai, bolna ai , and custom providers , allowing you to create intelligent voice based agents for customer support, sales, or general assistance problem statement building voice ai systems traditionally requires complex integrations across apis, telephony, and llms this node simplifies that process — enabling you to configure, connect, and manage a conversational ai voice agent directly inside your workflow without external coding requirements before using the voice agent node obtain a valid api key from your selected provider (e g , vapi, retell ai, bolna ai) have a working phone number setup in your provider dashboard ensure your webhook endpoint is properly generated and connected supported providers you can choose from multiple integrated voice ai providers provider description pricing type vapi enterprise grade voice ai platform with sub 600ms response times and tool integration pay per minute retell ai reliable ai for phone agents — supports testing, monitoring, and analytics pay per call bolna ai open source conversational ai supporting multiple llms and tts providers free / open source custom provider (beta) connect any third party or internal voice ai api endpoint custom outcome once configured, the node creates a fully functional ai voice agent capable of making or receiving phone calls generating conversational responses recording and transcribing calls handling multiple languages and accents how to use add the universal voice agent node drag and drop the voice agent node into your workflow it can act as a communication node that connects ai to human callers in real time configure ai provider (ai tab) under voice ai provider , select your preferred platform vapi retell ai bolna ai custom provider enter your api key (from the provider dashboard) optionally, provide an agent id for tracking and configuration each provider supports different models, voices, and maximum call durations — review them before selection 3️⃣ customize ai behavior (settings tab) field description example conversation prompt defines the agent’s tone and style of conversation “you are a helpful ai assistant ” system prompt core system level instruction for role definition “you are a professional customer service agent ” language sets the speaking language en us conversation mode defines type phone call or voice chat phone call max duration (seconds) time limit for the conversation 300 temperature controls creativity (0 = focused, 1 = creative) 0 7 max tokens restricts response length 150 end call phrase phrase that ends the call “goodbye” record call / transcribe call enable call recording or transcription ✅ enabled setup api & call parameters (api tab) webhook endpoint a webhook url is automatically generated for the agent used for handling events and responses from the provider example https //devapi simplita ai/voice agent/webhook used for handling events and responses from the provider phone call setup field description example from number (caller id) number shown to recipients +14157774444 to number (destination) number to call or connect +12137774445 phone number id id for tracking outbound calls (from vapi dashboard) ph 123xyz data storage setting select data retention preference everything (default) transcripts only metadata only enable signed urls (24h expiry) if secure data access is required database integration note (supabase) when using vapi , retell ai , or bolna ai providers, the conversation transcripts can be stored directly in supabase for long term access important you must create the appropriate table in your supabase database before storing transcripts for different agents , separate schemas or tables are required to maintain clear data organization and tracking