Get started

SignalWire is a programmable unified communications platform that unifies voice, messaging, video, and AI into a single control plane. SignalWire’s APIs and SDKs enable developers to build state-of-the-art realtime communication experiences without needing to manage complex telecom infrastructure or stitch together disconnected tools.

This guide will help you set up your account, explore the core APIs, and launch your first application.

Your SignalWire Space

When you create a SignalWire account, you also create a Space, like spacename.signalwire.com. Your Dashboard is located at that subdomain. In your Dashboard, you can:

• Buy and configure phone numbers
• Create and manage your applications
• View call logs and analytics
• Access your API credentials
• Set up AI agents, call flows, and more

Start building

Let’s begin by figuring out the best way for you to build. The right approach depends on what you’re creating and how you prefer to work.

What are you trying to build?

$
pip install signalwire-sdk

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from signalwire import AgentBase
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class MyAgent(AgentBase):
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    def __init__(self):
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        super().__init__(name="Assistant", route="/agent")
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        self.prompt_add_section("main", body="You are a helpful assistant for Acme Corp.")
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agent = MyAgent()
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if __name__ == "__main__":
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    agent.run()

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// Change from this (Twilio)
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const twilio = require("twilio");
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const client = twilio(ACCOUNT_SID, AUTH_TOKEN);
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// To this (SignalWire)
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const { RestClient } = require("@signalwire/compatibility-api");
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const client = RestClient(PROJECT_ID, API_TOKEN, {
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  signalwireSpaceUrl: "your-space.signalwire.com"
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});

Core concepts

Communication channels

SignalWire supports the following communication channels:

Most channels can work over different transports depending on how you want to connect:

For example, a voice call could come in via PSTN (someone dialing your number), SIP (from a desk phone), or WebRTC (from your web app). SignalWire will handle all three.

Phone numbers

To make or receive calls and messages through the phone network, you’ll need SignalWire phone numbers. You can buy local numbers, toll-free numbers, or short codes directly from your Dashboard or the API.

Each number can be configured to handle incoming calls and messages differently - whether that’s forwarding to another number, running a script, connecting to an AI agent, or triggering your own application.

We also offer the option of purchasing phone numbers programmatically via our Purchase a Phone Number API Endpoint.

Resources

In SignalWire, a Resource is anything that can handle communications - an AI agent, a script, a SIP connection, or your own application. When a call or message comes in, you tell SignalWire which Resource should handle it.

Common resource types include:

• SWML Scripts - Simple JSON/YAML instructions hosted in your Dashboard
• AI Agents - Conversational AI that handles calls autonomously
• Call Flows - Visual drag-and-drop call routing
• Relay Applications - Your own server applications connected via WebSocket

Addresses

Every Resource has an Address. This is a unique identifier that lets you target and interact with it. Think of addresses as the phone number for any resource, but broader in scope.

Addresses can be:

• Phone numbers - Traditional numbers like +14155551234 for PSTN calls
• SIP addresses - For VoIP connections like sip:user@domain.com
• Aliases - Custom names like /support-queue or /main-conference that are easy to remember

A single Resource can have multiple addresses, and you can change them anytime. For example, you might point both a phone number and a custom alias to the same AI agent.

Subscribers

Subscribers are end users who authenticate with SignalWire to make and receive calls. If you’re building a contact center, business phone system, or video conferencing app for example, your users become Subscribers.

SignalWire manages these users for you. You create, update, and delete them through our REST APIs, and each Subscriber gets:

• Authentication - Secure credentials and tokens for logging in
• A callable address - They can be reached directly at /private/username
• Multi-device support - They can answer calls from a browser, mobile app, or desk phone

This means you don’t have to build user management, authentication, or device registration yourself - SignalWire handles it.

Next Steps

Once you’ve chosen your path, here are some resources to help you along the way:

• Discord Community - Join 8,000+ developers. Great for questions and sharing what you’re building.
• GitHub - Example code, SDKs, and open source tools.
• API Reference - Detailed documentation for all our APIs.

If you get stuck or have questions, our support team is here to help at support@signalwire.com.

*Twilio and TwiML are trademarks of Twilio, Inc. SignalWire, Inc. and its products are not affiliated with or endorsed by Twilio, Inc.