Files
openclaw/extensions/voice-call
JayMishra-github 2c6db57554 feat(voice-call): pre-cache inbound greeting for instant playback
Pre-generates TTS audio for the configured inboundGreeting at startup
and serves it instantly when an inbound call connects, eliminating the
500ms+ TTS synthesis delay on the first ring.

Changes:
- twilio.ts: Add cachedGreetingAudio storage with getter/setter
- runtime.ts: Pre-synthesize greeting TTS after provider initialization
- webhook.ts: Play cached audio directly via media stream on inbound
  connect, falling back to the original TTS path for outbound calls
  or when no cached audio is available

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-02-16 23:52:36 +01:00
..
2026-02-16 06:08:47 +01:00
2026-02-16 06:08:47 +01:00

@openclaw/voice-call

Official Voice Call plugin for OpenClaw.

Providers:

  • Twilio (Programmable Voice + Media Streams)
  • Telnyx (Call Control v2)
  • Plivo (Voice API + XML transfer + GetInput speech)
  • Mock (dev/no network)

Docs: https://docs.openclaw.ai/plugins/voice-call Plugin system: https://docs.openclaw.ai/plugin

Install (local dev)

openclaw plugins install @openclaw/voice-call

Restart the Gateway afterwards.

Option B: copy into your global extensions folder (dev)

mkdir -p ~/.openclaw/extensions
cp -R extensions/voice-call ~/.openclaw/extensions/voice-call
cd ~/.openclaw/extensions/voice-call && pnpm install

Config

Put under plugins.entries.voice-call.config:

{
  provider: "twilio", // or "telnyx" | "plivo" | "mock"
  fromNumber: "+15550001234",
  toNumber: "+15550005678",

  twilio: {
    accountSid: "ACxxxxxxxx",
    authToken: "your_token",
  },

  telnyx: {
    apiKey: "KEYxxxx",
    connectionId: "CONNxxxx",
    // Telnyx webhook public key from the Telnyx Mission Control Portal
    // (Base64 string; can also be set via TELNYX_PUBLIC_KEY).
    publicKey: "...",
  },

  plivo: {
    authId: "MAxxxxxxxxxxxxxxxxxxxx",
    authToken: "your_token",
  },

  // Webhook server
  serve: {
    port: 3334,
    path: "/voice/webhook",
  },

  // Public exposure (pick one):
  // publicUrl: "https://example.ngrok.app/voice/webhook",
  // tunnel: { provider: "ngrok" },
  // tailscale: { mode: "funnel", path: "/voice/webhook" }

  outbound: {
    defaultMode: "notify", // or "conversation"
  },

  streaming: {
    enabled: true,
    streamPath: "/voice/stream",
  },
}

Notes:

  • Twilio/Telnyx/Plivo require a publicly reachable webhook URL.
  • mock is a local dev provider (no network calls).
  • Telnyx requires telnyx.publicKey (or TELNYX_PUBLIC_KEY) unless skipSignatureVerification is true.
  • tunnel.allowNgrokFreeTierLoopbackBypass: true allows Twilio webhooks with invalid signatures only when tunnel.provider="ngrok" and serve.bind is loopback (ngrok local agent). Use for local dev only.

TTS for calls

Voice Call uses the core messages.tts configuration (OpenAI or ElevenLabs) for streaming speech on calls. You can override it under the plugin config with the same shape — overrides deep-merge with messages.tts.

{
  tts: {
    provider: "openai",
    openai: {
      voice: "alloy",
    },
  },
}

Notes:

  • Edge TTS is ignored for voice calls (telephony audio needs PCM; Edge output is unreliable).
  • Core TTS is used when Twilio media streaming is enabled; otherwise calls fall back to provider native voices.

CLI

openclaw voicecall call --to "+15555550123" --message "Hello from OpenClaw"
openclaw voicecall continue --call-id <id> --message "Any questions?"
openclaw voicecall speak --call-id <id> --message "One moment"
openclaw voicecall end --call-id <id>
openclaw voicecall status --call-id <id>
openclaw voicecall tail
openclaw voicecall expose --mode funnel

Tool

Tool name: voice_call

Actions:

  • initiate_call (message, to?, mode?)
  • continue_call (callId, message)
  • speak_to_user (callId, message)
  • end_call (callId)
  • get_status (callId)

Gateway RPC

  • voicecall.initiate (to?, message, mode?)
  • voicecall.continue (callId, message)
  • voicecall.speak (callId, message)
  • voicecall.end (callId)
  • voicecall.status (callId)

Notes

  • Uses webhook signature verification for Twilio/Telnyx/Plivo.
  • responseModel / responseSystemPrompt control AI auto-responses.
  • Media streaming requires ws and OpenAI Realtime API key.