About • How It Works • Documentation • Quickstart • Skills • Templates

Patter is the open-source SDK that gives your AI agent a phone number. You build the agent; Patter handles everything between it and the phone network — the agent loop, the language model, speech-to-text, text-to-speech, real-time voice, audio processing, and the telephony carrier.

• Build with one API in Python or TypeScript — same surface, same hooks, same events, at full parity.
• Choose the provider for every layer — LLM, STT, TTS, realtime engine, carrier — and swap any of them with one line.
• Run locally with a built-in tunnel and dashboard, or simulate a whole call from your terminal — no phone required.

Patter is the full voice stack between your application and the phone network — not just glue between an LLM and a carrier. It runs the agent loop and owns every layer of the call, and you pick the provider for each one. Compose them in Realtime, Pipeline, or Hybrid mode.

27+ provider integrations across the voice stack · 3 voice modes · 2 SDKs (Python & TypeScript) at parity.

On top of the stack: an automatic LLM fallback chain (provider failover mid-call), built-in tools / call transfer / guardrails that behave identically on every carrier, and a vendor-neutral OpenTelemetry trace of each call.

Visit the docs, or jump straight to a quickstart: TypeScript · Python.

Using Claude Code, Claude Desktop, OpenClaw, Hermes, Cursor, Codex, or another AI coding agent?

Install Patter skills for voice agents →

npx skills add patterai/skills

The bundle works in ~55 agent harnesses that consume the Anthropic Agent Skills standard. Install once; every agent on your machine learns the SDK. Skills live in their own repository: PatterAI/skills.

Provider and carrier credentials are read from environment variables (e.g. TWILIO_ACCOUNT_SID, OPENAI_API_KEY) — the docs list the full catalog. Swap Twilio for Telnyx or Plivo to change carrier.

npm install getpatter

import { Patter, Twilio, OpenAIRealtime } from "getpatter";

const phone = new Patter({ carrier: new Twilio(), phoneNumber: "+15550001234" });
const agent = phone.agent({
  engine: new OpenAIRealtime(),
  systemPrompt: "You are a friendly receptionist for Acme Corp.",
  firstMessage: "Hello! How can I help?",
});
await phone.serve({ agent, tunnel: true });

pip install getpatter

from getpatter import Patter, Twilio, OpenAIRealtime

phone = Patter(carrier=Twilio(), phone_number="+15550001234")
agent = phone.agent(
    engine=OpenAIRealtime(),
    system_prompt="You are a friendly receptionist for Acme Corp.",
    first_message="Hello! How can I help?",
)
await phone.serve(agent, tunnel=True)

tunnel: true spawns a Cloudflare quick tunnel and points your number at it — ideal for local dev. For production, use a static webhook_url (or ngrok); see Tunneling.

Note Patter collects anonymous, opt-out usage data (SDK version, bucketed provider/model and call facts) to help us prioritise — never call content, prompts, phone numbers, keys, or free text.

Opt out any time: Patter(telemetry=False) (new Patter({ telemetry: false })), getpatter telemetry disable, or PATTER_TELEMETRY_DISABLED=1 (also honours DO_NOT_TRACK=1); auto-off in CI/tests. Inspect without sending: PATTER_TELEMETRY_DEBUG=1. Full details: Telemetry.

Each template is a self-contained repo — clone, add your .env, and run. Python and TypeScript both included.

git clone https://github.com/PatterAI/patter-inbound-agent
cd patter-inbound-agent
cp .env.example .env    # fill in your keys
cd python && pip install -r requirements.txt && python main.py

Thanks to all our amazing contributors!

MIT — see LICENSE.