Supercall

SuperCall

Make AI-powered phone calls with custom personas and goals using OpenAI Realtime API + Twilio.

Features

• Persona Calls: Define a persona, goal, and opening line for autonomous calls
• Full Realtime Mode: GPT-4o powered voice conversations with <~1s latency
• DTMF / IVR Navigation: AI automatically navigates automated phone menus (press 1 for X, enter your account number, etc.) by generating and injecting touch-tone digits into the audio stream
• Provider: Supports Twilio (full realtime) and mock provider for testing
• Streaming Audio: Bidirectional audio via WebSocket for real-time conversations
• Limited Access: Unlike the standard voice_call plugin, the person on the call doesn't have access to gateway agent, reducing attack surfaces.

Credentials

Required

Optional

Credentials can be set via environment variables or in the plugin config (config takes precedence).

Installation

1. Install the plugin via npm or copy to your OpenClaw extensions directory

2. Enable hooks for call completion callbacks (required):

{
  "hooks": {
    "enabled": true,
    "token": "your-secret-token"
  }
}

Generate a secure token with: openssl rand -hex 24

⚠️ Security: The hooks.token is sensitive — it authenticates internal callbacks. Keep it secret and rotate if compromised.

3. Configure the plugin in your openclaw config:

{
  "plugins": {
    "entries": {
      "supercall": {
        "enabled": true,
        "config": {
          "provider": "twilio",
          "fromNumber": "+15551234567",
          "twilio": {
            "accountSid": "your-account-sid",
            "authToken": "your-auth-token"
          },
          "streaming": {
            "openaiApiKey": "your-openai-key"
          },
          "tunnel": {
            "provider": "ngrok",
            "ngrokDomain": "your-domain.ngrok.app"
          }
        }
      }
    }
  }
}

Important: The hooks.token is required for call completion callbacks. Without it, the agent won't be notified when calls finish.

Tool: supercall

Make phone calls with custom personas:

supercall(
  action: "persona_call",
  to: "+1234567890",
  persona: "Personal assistant to the king",
  goal: "Confirm the callee's availabilities for dinner next week",
  openingLine: "Hey, this is Michael, Alex's Assistant..."
)

Actions

• persona_call - Start a new call with a persona
• get_status - Check call status and transcript
• end_call - End an active call
• list_calls - List active persona calls

DTMF / IVR Navigation

The AI automatically handles automated phone menus (IVR systems) during calls. When it hears prompts like "press 1 for sales", it uses an internal send_dtmf tool to send touch-tone digits through the audio stream. This is fully automatic — no extra configuration or agent intervention is needed.

• Supported characters: 0-9, *, #, A-D, w (500ms pause)
• Example sequences: 1 (press 1), 1234567890# (enter account number + pound), 1w123# (press 1, wait, then enter 123#)
• How it works: DTMF tones are generated as ITU-standard dual-frequency pairs, encoded to µ-law (8kHz mono), and injected directly into the Twilio media stream. No external dependencies.

This means persona calls can navigate phone trees end-to-end — e.g., "call the pharmacy, navigate through their menu, and check on my prescription status."

Configuration Options

Requirements

• Node.js 20+
• Twilio account for full realtime calls (media streams)
• ngrok or Tailscale for webhook tunneling (production)
• OpenAI API key for real-time features

Architecture

This is a fully standalone skill - it does not depend on the built-in voice-call plugin. All voice calling logic is self-contained.

Runtime Behavior and Security

This plugin is not instruction-only. It runs code, spawns processes, opens network listeners, and writes to disk. The following describes exactly what happens at runtime.

Process spawning

When tunnel.provider is set to ngrok, the plugin spawns the ngrok CLI binary via child_process.spawn. When set to tailscale-serve or tailscale-funnel, it spawns the tailscale CLI instead. These processes run for the lifetime of the plugin and are terminated on shutdown. If tunnel.provider is none (or a publicUrl is provided directly), no external processes are spawned.

Network activity

• Local webhook server: The plugin opens an HTTP server (default 0.0.0.0:3335) to receive Twilio webhook callbacks and WebSocket media streams.
• Startup self-test: On startup, the plugin sends an HTTP POST to its own public webhook URL with an x-supercall-self-test header to verify connectivity. If publicUrl is misconfigured to point at an unintended endpoint, this self-test token could be sent there. Always verify your publicUrl or tunnel configuration before starting.
• Outbound API calls: The plugin makes outbound requests to the OpenAI Realtime API (WebSocket) and Twilio REST API during calls.

Webhook verification

• Twilio calls: Verified using Twilio's X-Twilio-Signature header (HMAC-SHA1).
• Self-test requests: Authenticated using an internal token (x-supercall-self-test) generated at startup.
• ngrok free-tier relaxation: On free-tier ngrok domains (.ngrok-free.app, .ngrok.io), URL reconstruction may vary due to ngrok's request rewriting; Twilio signature mismatches are logged but allowed through. Paid/custom ngrok domains (.ngrok.app) are verified strictly. This relaxation is limited to free-tier domains only and does not affect Tailscale or direct publicUrl configurations.

Data at rest

Call transcripts are persisted to ~/clawd/supercall-logs. These logs may contain sensitive conversation content. Review and rotate logs periodically.

Best practices

• Protect your credentials — Twilio and OpenAI keys grant access to paid services
• Verify your public URL — ensure publicUrl or tunnel config points where you expect before starting
• Rotate hooks.token periodically and if you suspect compromise
• Review call logs — transcripts stored on disk may contain sensitive content