--- summary: "Voice Call plugin: outbound + inbound calls via Twilio/Telnyx/Plivo (plugin install + config + CLI)" read_when: - You want to place an outbound voice call from OpenClaw - You are configuring or developing the voice-call plugin title: "Voice Call Plugin" --- # Voice Call (plugin) Voice calls for OpenClaw via a plugin. Supports outbound notifications and multi-turn conversations with inbound policies. Current providers: - `twilio` (Programmable Voice + Media Streams) - `telnyx` (Call Control v2) - `plivo` (Voice API + XML transfer + GetInput speech) - `mock` (dev/no network) Quick mental model: - Install plugin - Restart Gateway - Configure under `plugins.entries.voice-call.config` - Use `openclaw voicecall ...` or the `voice_call` tool ## Where it runs (local vs remote) The Voice Call plugin runs **inside the Gateway process**. If you use a remote Gateway, install/configure the plugin on the **machine running the Gateway**, then restart the Gateway to load it. ## Install ### Option A: install from npm (recommended) ```bash openclaw plugins install @openclaw/voice-call ``` Restart the Gateway afterwards. ### Option B: install from a local folder (dev, no copying) ```bash openclaw plugins install ./extensions/voice-call cd ./extensions/voice-call && pnpm install ``` Restart the Gateway afterwards. ## Config Set config under `plugins.entries.voice-call.config`: ```json5 { plugins: { entries: { "voice-call": { enabled: true, config: { provider: "twilio", // or "telnyx" | "plivo" | "mock" fromNumber: "+15550001234", toNumber: "+15550005678", twilio: { accountSid: "ACxxxxxxxx", authToken: "...", }, telnyx: { apiKey: "...", connectionId: "...", // 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: "...", }, // Webhook server serve: { port: 3334, path: "/voice/webhook", }, // Webhook security (recommended for tunnels/proxies) webhookSecurity: { allowedHosts: ["voice.example.com"], trustedProxyIPs: ["100.64.0.1"], }, // Public exposure (pick one) // publicUrl: "https://example.ngrok.app/voice/webhook", // tunnel: { provider: "ngrok" }, // tailscale: { mode: "funnel", path: "/voice/webhook" } outbound: { defaultMode: "notify", // notify | conversation }, streaming: { enabled: true, streamPath: "/voice/stream", preStartTimeoutMs: 5000, maxPendingConnections: 32, maxPendingConnectionsPerIp: 4, maxConnections: 128, }, }, }, }, }, } ``` Notes: - Twilio/Telnyx require a **publicly reachable** webhook URL. - Plivo requires 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. - `skipSignatureVerification` is for local testing only. - If you use ngrok free tier, set `publicUrl` to the exact ngrok URL; signature verification is always enforced. - `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. - Ngrok free tier URLs can change or add interstitial behavior; if `publicUrl` drifts, Twilio signatures will fail. For production, prefer a stable domain or Tailscale funnel. - Streaming security defaults: - `streaming.preStartTimeoutMs` closes sockets that never send a valid `start` frame. - `streaming.maxPendingConnections` caps total unauthenticated pre-start sockets. - `streaming.maxPendingConnectionsPerIp` caps unauthenticated pre-start sockets per source IP. - `streaming.maxConnections` caps total open media stream sockets (pending + active). ## Stale call reaper Use `staleCallReaperSeconds` to end calls that never receive a terminal webhook (for example, notify-mode calls that never complete). The default is `0` (disabled). Recommended ranges: - **Production:** `120`–`300` seconds for notify-style flows. - Keep this value **higher than `maxDurationSeconds`** so normal calls can finish. A good starting point is `maxDurationSeconds + 30–60` seconds. Example: ```json5 { plugins: { entries: { "voice-call": { config: { maxDurationSeconds: 300, staleCallReaperSeconds: 360, }, }, }, }, } ``` ## Webhook Security When a proxy or tunnel sits in front of the Gateway, the plugin reconstructs the public URL for signature verification. These options control which forwarded headers are trusted. `webhookSecurity.allowedHosts` allowlists hosts from forwarding headers. `webhookSecurity.trustForwardingHeaders` trusts forwarded headers without an allowlist. `webhookSecurity.trustedProxyIPs` only trusts forwarded headers when the request remote IP matches the list. Webhook replay protection is enabled for Twilio and Plivo. Replayed valid webhook requests are acknowledged but skipped for side effects. Twilio conversation turns include a per-turn token in `` callbacks, so stale/replayed speech callbacks cannot satisfy a newer pending transcript turn. Example with a stable public host: ```json5 { plugins: { entries: { "voice-call": { config: { publicUrl: "https://voice.example.com/voice/webhook", webhookSecurity: { allowedHosts: ["voice.example.com"], }, }, }, }, }, } ``` ## 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** — it deep‑merges with `messages.tts`. ```json5 { tts: { provider: "elevenlabs", elevenlabs: { voiceId: "pMsXgVXv3BLzUgSXRplE", modelId: "eleven_multilingual_v2", }, }, } ``` 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. ### More examples Use core TTS only (no override): ```json5 { messages: { tts: { provider: "openai", openai: { voice: "alloy" }, }, }, } ``` Override to ElevenLabs just for calls (keep core default elsewhere): ```json5 { plugins: { entries: { "voice-call": { config: { tts: { provider: "elevenlabs", elevenlabs: { apiKey: "elevenlabs_key", voiceId: "pMsXgVXv3BLzUgSXRplE", modelId: "eleven_multilingual_v2", }, }, }, }, }, }, } ``` Override only the OpenAI model for calls (deep‑merge example): ```json5 { plugins: { entries: { "voice-call": { config: { tts: { openai: { model: "gpt-4o-mini-tts", voice: "marin", }, }, }, }, }, }, } ``` ## Inbound calls Inbound policy defaults to `disabled`. To enable inbound calls, set: ```json5 { inboundPolicy: "allowlist", allowFrom: ["+15550001234"], inboundGreeting: "Hello! How can I help?", } ``` Auto-responses use the agent system. Tune with: - `responseModel` - `responseSystemPrompt` - `responseTimeoutMs` ## CLI ```bash openclaw voicecall call --to "+15555550123" --message "Hello from OpenClaw" openclaw voicecall continue --call-id --message "Any questions?" openclaw voicecall speak --call-id --message "One moment" openclaw voicecall end --call-id openclaw voicecall status --call-id openclaw voicecall tail openclaw voicecall expose --mode funnel ``` ## Agent 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) This repo ships a matching skill doc at `skills/voice-call/SKILL.md`. ## Gateway RPC - `voicecall.initiate` (`to?`, `message`, `mode?`) - `voicecall.continue` (`callId`, `message`) - `voicecall.speak` (`callId`, `message`) - `voicecall.end` (`callId`) - `voicecall.status` (`callId`)