Give your AI agents real phone numbers — inbound and outbound calls, BYO AI model
Developer-friendly REST API for AI-powered phone calls. You bring the AI — we handle telephony, billing, numbers, recordings, and call management.
The BubblyPhone AI Voice Agent API gives developers a programmatic way to connect AI agents to real phone calls — purchase phone numbers, handle inbound and outbound voice, transcribe conversations, record audio, and let your AI use tools mid-call, all through a simple REST API.
Unlike closed voice AI platforms, BubblyPhone is BYOK: bring any LLM (OpenAI, Anthropic, Google, or your own model) and any voice provider. Two integration modes fit any architecture — Webhook Mode for full control over conversation flow, or Streaming Mode for sub-second real-time audio bridging with models like Gemini 3.1 Flash Live and GPT Realtime.
Prepaid per-minute billing starts at $0.04/min inbound, $0.05/min outbound, with phone numbers from $3/month and coverage across 200+ countries.
import bubblyphone
client = bubblyphone.Client(api_key="your_api_key")
# 1. Buy a phone number
number = client.numbers.purchase(country="US")
# 2. Point it at your AI via webhook
client.numbers.configure(
number.id,
webhook_url="https://your-app.com/ai-handler",
)
# 3. Incoming calls now hit your AI.
# Transcripts, recordings, and billing are handled for you.Open-source MCP server works with Claude Code, Claude Desktop, Cursor, Codex, and any MCP-compatible client. Make calls, manage numbers, and check usage — without leaving your editor.
{
"mcpServers": {
"bubblyphone": {
"command": "npx",
"args": ["@bubblyphone/mcp-server"],
"env": {
"BUBBLYPHONE_API_KEY": "bp_live_sk_your_key_here"
}
}
}
}Prefer remote? Point any MCP client at https://agents.bubblyphone.com/mcp
Purchase a phone number via API. From $3/month.
Set a webhook URL or choose streaming mode with your AI model.
Incoming calls hit your AI. Transcripts, recordings, and billing handled.
A complete toolkit for AI voice agents — numbers, calls, recordings, and safety controls.
Any LLM. Any STT. Any TTS. No vendor lock-in.
Real-time transcripts for every call.
Automatic recording with API access.
AI can call functions mid-conversation.
Per-key budgets, hard and soft limits.
Per-key rate limits + IP whitelisting.
Global coverage with transparent rates.
Multiple keys with scoped permissions.
Choose the integration style that fits your architecture
Events sent to your endpoint. You respond with actions. Works with any stack.
Real-time audio bridge between caller and your AI model. Sub-second latency.
Common use cases for AI phone agents
Pay as you go. No contracts. No minimums.
Outbound calls
$0.05/min
Inbound calls
$0.04/min
Phone numbers (US)
$3/mo
BYOK (Bring Your Own Key) — use your own LLM API key and skip model charges. International numbers available from $5/mo. See full pricing →
BYOK. Use any model, switch anytime. Your AI, your infrastructure.
Prepaid credit. Top up $10 or $5,000. No contracts, cancel anytime.
Webhook for full control. Streaming for simplicity. Choose what fits.
A REST API that lets developers give their AI agents real phone numbers. Your AI can make outbound calls, answer inbound calls, record conversations, and use tools mid-call. You bring the LLM and voice models; BubblyPhone handles telephony, billing, and call management.
Yes. BubblyPhone ships an open-source MCP (Model Context Protocol) server that plugs into Claude Code, Claude Desktop, Cursor, Codex, and any MCP-compatible client. You can make calls, manage phone numbers, check billing, fetch transcripts, and inject context into live calls — all from your coding agent.
You provide your own API key for your LLM (OpenAI, Anthropic, Google, etc.) and voice models. BubblyPhone never charges you for model inference — you pay your AI vendor directly at their rates and pay us only for the phone call minutes and numbers.
Webhook Mode sends call events to your HTTP endpoint and you respond with actions — full control, works with any stack. Streaming Mode opens a real-time audio bridge between the caller and your AI model (Gemini 3.1 Flash Live, GPT Realtime, etc.) with sub-second latency and built-in tool calling.
Any model with an API. Streaming Mode has first-class support for Gemini 3.1 Flash Live, GPT Realtime, and other realtime voice models. Webhook Mode works with any LLM you can call over HTTP.
Prepaid credit, pay-as-you-go. $0.05/min outbound calls, $0.04/min inbound calls, $3/mo for US phone numbers (international from $5/mo). No monthly fees, no minimum spend, no contracts.
Yes. Every call can be automatically recorded and transcribed. Recordings are accessible via API, transcripts are generated in real-time and stored alongside each call.
200+ countries for outbound calls. Phone numbers available in the US, UK, EU, and other major markets.
Sign up at agents.bubblyphone.com/register (free, no credit card required), generate an API key, purchase a phone number, and make your first call.
Start building in minutes. No credit card required.