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The IVR toolkit is CallFactory’s developer-focused action library for building custom call flows. Each action — Answer, Play, Dial, Record, and StartStream — gives you precise control over what happens during a call, so your logic isn’t constrained by a dashboard interface.
You use the toolkit to build choice menus, gather caller input, stream audio to AI services, connect callers with agents, and handle edge cases cleanly. The toolkit runs on the same IVR platform that powers all standard CallFactory features, so you get the same building blocks that our own product teams use.
- Structured actions with clear signatures and examples
- Stream audio to AI, STT, or your own endpoint
- Build complete call flows without extra hardware
- Full documentation and developer support
Benefits of the IVR Toolkit
See how the IVR toolkit helps development teams build professional call flows that align precisely with their backend and processes.
Complete control over call logic
You decide what happens at each step of a call because you play prompts, gather input, route on conditions, stream to AI, and handle errors with predictable, well-documented actions.
Built for developers
Each action has a clear signature, typed return values, error handling, and working code examples, so you build with confidence using structured actions that fit naturally into your backend.
AI-ready audio streaming
You stream live call audio to any WebSocket endpoint — an AI assistant, a speech-to-text engine, or your own analytics service — with StartStream and StopStream giving you complete control over when and where audio flows.
Runs on proven infrastructure
The toolkit runs on CallFactory's own IVR platform, the same infrastructure that powers all our telephony features, so you need no extra hardware or third-party dependencies and everything works with your existing CallFactory numbers.
How the IVR Toolkit Works
The IVR toolkit is a library of actions that your code calls during a live call. Once a call arrives your application receives it, then you decide step by step what happens using these actions.
A typical flow starts with Answer(), plays a welcome message with Play(), gathers input via PromptDigit() or GatherDigits(), and routes the caller with Dial() and Connect(). Each action returns a typed result, so your code always knows what happened and can handle every possible outcome cleanly.
Audio Streaming for AI and Speech-to-Text
With the StartStream and StopStream actions you stream live call audio in real time to any WebSocket endpoint. This connects a call with an AI assistant, a speech-to-text engine, or your own analytics service, without buffering audio first or routing it in a roundabout way.
You control when the stream starts, which direction audio flows (caller to AI, agent to AI, or both at once), and when it stops. The stream runs parallel to your other IVR actions, so you can play prompts, gather input, or transfer calls while AI listens in the background.
Who Uses the IVR Toolkit
The toolkit is designed for development teams who need complete control over call behavior. Think of SaaS platforms adding voice features to their product, contact centers building their own routing logic, and companies integrating telephony with their CRM, ERP, or internal tools.
If you have a team of developers writing backend code, the IVR toolkit gives you everything you need to build professional call flows, from simple menus to complex AI-driven conversations. Documentation, code examples, and developer support are included, so your team stays productive without having to invent integration patterns on your own.
The Relationship Between Toolkit and Platform Features
Every CallFactory feature — like the selection menu, the call queue, voicemail and the voicebot — is built from the same IVR actions documented in this toolkit. The toolkit gives you direct access to those same building blocks, so you work at the same level as our own product teams.
This means everything CallFactory does by default can also be done by your development team, and often more. You combine standard features with custom logic, add integrations that don’t exist as a standard feature, and build call flows that fully align with how your own business operates.
Getting Started
Contact us to discuss your needs, then we give your team access to the toolkit documentation, working code examples, and a development environment. If you need help designing your first call flow, our team advises on architecture and shares best practices we see work in similar implementations.
For organizations that need complete capacity and isolation, dedicated IVR servers is the natural next step, where your custom call flows run on an environment reserved entirely for you.
Learn More About Other Features
Find more information about our features that can improve your business communication.
Voicebot
AI-powered voice assistants built on our IVR platform. Automate incoming calls with natural conversation, data lookups, and smart routing.
Dedicated IVR servers
Your own IVR server with complete control. Build custom telephony applications, connect AI platforms, and scale from 4 to 200+ channels. The natural upgrade from our private API when you need more.
API integrations
Tell us what you need, we build the endpoints. Our private API lets you integrate CallFactory telephony into your own software — no generic library, no guesswork, no wasted development time.
IVR Toolkit — Frequently Asked Questions
Find clear answers to questions about the IVR toolkit and how it works in practice for your business.
Yes. The toolkit is a library of actions your own backend calls, which means your development team writes each call flow in code. If you don’t have developers in-house, our ready-made custom telephony and voicebot options are often a better starting point.
You program in any common language because your code runs in a virtual machine we host for you. Documentation, actions, and examples use C# (.NET) as the primary language, but you’re not locked into C# if your team prefers another language.
Yes. The StartStream action opens a real-time WebSocket connection to any endpoint you specify, whether an AI assistant, a speech-to-text engine, or your own service. You control the audio direction and can stop the stream at any time.
Yes. All IVR actions work with your existing CallFactory numbers and routing, so you don’t need to change your phone setup.
Yes. The toolkit uses the same building blocks as all CallFactory features, so you can keep using standard features like selection menus and call queues alongside your custom logic.
Every action supports cancellation tokens, so the token is canceled the moment the caller hangs up and your code gets a clear signal to stop. No stray connections or unhandled states remain.
Yes. Our team advises on architecture, reviews your flow design, and helps with more complex integrations. For fully managed solutions, our custom telephony and voicebot services are a logical next step.
The toolkit is available to CallFactory customers. Depending on the complexity of your implementation and hosting requirements, additional costs may apply. We always discuss pricing before work begins.
