Introducing CrazyAI Voice API: Outbound AI Phone Calls and Retail AUD Pricing

We are excited to launch the CrazyAI Voice API - giving Grok Bot, ChatGPT, Claude, and your booking or CRM software a real Australian phone line on the Crazytel network.

With a single HTTPS request containing just a phone number (destination) and what to say (initial_text), your AI assistant or automation workflow can dial any Australian mobile or landline from your own Crazytel Hybrid SIP Trunk Caller ID, speak in a natural human-like voice, listen to the person who answers, and return their exact spoken reply as text (callee_transcript).

Built for Modern AI Assistants, Booking Systems, and CRMs

Connecting text-based AI agents and business software to the real telephone network traditionally meant building SIP trunks, WebRTC media servers, and real-time audio pipelines from scratch. CrazyAI Voice API handles all of the telephony and speech engineering behind a clean REST API:

• Grok Bot and xAI Agents - Powered natively by grok-voice-3.0 (speech-to-speech) and grok-voice-transcribe-2.0 (speech-to-text). Save your standing persona in the portal and pass call-specific goals via append_instructions.
• ChatGPT, Claude, and MCP Agents - Connect ChatGPT Custom Actions or Claude Model Context Protocol (MCP) tools without processing raw audio. Send a phone number and message, and receive clean JSON with callee_transcript and callee_reply_intent (affirmative, negative, or neutral).
• Booking, Medical, and Appointment Confirmations - Automate appointment reminders for dental clinics, medical practices, salons, and professional services, complete with smart yes/no goodbyes or live call transfers to reception.
• Field Service, Tradies, and CRM Workflows - Trigger calls from n8n, Make, Zapier, HubSpot, ServiceM8, or your own CRM to confirm someone is home, check gate codes, or notify customers when a technician is on the way.

How It Works in 3 Simple Steps

1. Pick a Phone Line and Voice (Once) - In MyAccount, select which of your Crazytel PAYG Hybrid SIP Trunks to dial out from (or create a new Hybrid SIP Trunk inline in seconds) and choose one of 28 natural voices across 21 languages.
2. Copy Your Profile ID (profile_uuid) - Your phone line, verified Australian Caller ID, AI voice, voicemail rules, and polite goodbye settings are all saved inside one reusable Profile ID.
3. Make Calls with Just 2 Fields - Send destination and initial_text to POST https://api.crazytel.io/api/v1/crazyai-voice-api/{profile_uuid}/calls. Crazytel dials the number, speaks your message, transcribes the answer, and returns the result as JSON.

Three Call Modes in One API

Every Voice Profile supports three call modes that you can set as a default in the portal or switch per call in the API:

• 1. Quick Message and Reply (single_turn - Default) - Dials the number, speaks your opening question, transcribes the person's reply and intent, speaks a smart conditional goodbye based on whether they said yes or no, and hangs up cleanly.
• 2. Back-and-Forth Conversation (interactive) - Keeps the phone line open (awaiting_next_turn) after the first reply so your AI bot can drive a multi-turn conversation via /say, navigate IVR menus with /dtmf, transfer the live call to staff via /refer, or hang up via /hangup.
• 3. Full AI Phone Agent (grok_voice_agent) - Autonomous grok-voice-3.0 speech-to-speech agent conducts the entire conversation in real time using your saved default_instructions and per-call append_instructions or instructions.

Key Features Engineered for Real Australian Calls

• Smart Answer-Dependent Goodbyes (closing_message_mode) - In single_turn mode, automatically speak a tailored positive sign-off when the customer confirms, a negative sign-off when they decline, or hold the line briefly (wait_for_bot) for your bot to send a custom closing message.
• Crazyswitch AI Voicemail Detection (AMD) - Combines free tone and regex detection with Crazyswitch AI AMD classification and automatic beep detection (440 - 1500 Hz). Choose to wait for the beep and leave a voicemail (leave_voicemail), hang up immediately at $0.00 AUD TTS cost (terminate), report voicemail back to your bot (report_only), or continue normally (nothing).
• Live Call Transfers to Your Staff (SIP REFER) - Transfer an active call via native Hybrid SIP REFER to internal staff extensions (such as 101), call park slots (700), Australian phone numbers, or sip: URIs, with optional spoken transfer announcements and an approved transfer target allowlist.
• 28 Natural Voices, 21 Languages, and Australian Vocabulary - Choose from 28 lifelike voices (including Eve, Ara, Rex, Sal, and Leo), add expressive speech tags ([pause], [chuckle], <soft>, <slow>), and teach the engine Australian suburb names and brand pronunciations with keyterms and pronunciation_replace.
• Built-In Safety Guardrails and Signed Webhooks - Configurable max call duration, ring timeout, idle timeout, a 5-call concurrency cap, a 5-second duplicate-destination cooldown, and HMAC-SHA256 signed webhooks (X-Crazytel-Signature-256).

Retail AUD Pricing Schedule (No Monthly Subscription Fee)

CrazyAI Voice API has no monthly subscription fee, and unanswered or busy calls cost $0.00 AUD in AI Voice usage. Connected calls have two transparent components, rated in Australian Dollars (AUD). You can view the full schedule anytime at crazytel.com.au/crazyai-voice-api/#pricing.

Charge 1: CrazyAI Voice API Usage (AUD)

Charge 2: Outbound Phone Call Leg (PAYG Hybrid SIP Trunk)

• Every outbound call dials out through the Crazytel Hybrid SIP Trunk (hybrid.sip.crazytel.net.au) linked to your Voice Profile using that trunk's verified Australian Caller ID.
• The standard phone call leg is billed separately on your Hybrid SIP Trunk's Pay-As-You-Go (PAYG) call rates.
• PAYG Plans Only - Because CrazyAI Voice API places automated programmatic outbound calls, linked Hybrid SIP Trunks must be on a PAYG plan (bundled or included-minute plans do not apply to automated AI Voice API calls).

Get Started Today

CrazyAI Voice API is live now. Head to crazytel.com.au/crazyai-voice-api/ to explore the call modes and retail AUD pricing, create your first Voice Profile in MyAccount, or dive straight into the interactive OpenAPI documentation at crazytel.io/docs.