Patter SDK
Patter is an open-source SDK that gives an AI agent a phone number, handling the agent loop, speech-to-text, text-to-speech, real-time voice and the telephony carrier in one Python or TypeScript API so a developer can swap any provider in that stack with one line.
Patter is an open-source voice-AI SDK that runs the full stack between an application and the phone network rather than just gluing a language model to a carrier. It owns every layer of a call, including the agent loop, the language model, speech-to-text, text-to-speech, real-time voice, audio processing and the telephony carrier, while letting a developer choose the provider for each layer independently.
It offers more than 27 provider integrations across language models, speech-to-text, text-to-speech, realtime engines, telephony carriers such as Twilio, Telnyx and Plivo, and audio processing, composed in Realtime, Pipeline or Hybrid modes. Built-in features include an automatic LLM fallback chain for provider failover mid-call, call transfer and guardrails that behave the same on every carrier, and a vendor-neutral OpenTelemetry trace of each call. It also runs locally with a built-in tunnel and dashboard, or simulates a call from the terminal with no phone required.