Key Concepts

This page defines the core terms and concepts used throughout BuildVoiceAI. Understanding these will help you navigate the platform and documentation more effectively.

Agency

Your top-level organization account. When you sign up for BuildVoiceAI, you create an agency. Everything in the platform — agents, clients, calls, workflows, integrations — belongs to your agency. If you’re an AI voice agency serving multiple businesses, your agency is the parent account that manages all of them.

Client

A sub-account you create within your agency to represent one of your customers. Each client is isolated with their own:

Agents assigned to them
Call history and analytics
Optional portal login for self-service access

Clients allow you to organize your work by customer and control what each customer can see. Your plan tier determines how many active clients you can have.

Agent

An AI voice assistant configured to handle phone conversations autonomously. Each agent has:

A prompt — Written instructions that define the agent’s personality, role, knowledge, and conversation behavior.
A voice — The synthesized voice it speaks with, selected from your voice provider’s options.
A phone number (optional) — A dedicated number for receiving inbound calls and making outbound calls.
A knowledge base (optional) — Documents and data the agent can reference during conversations.

Agents are the core building block of the platform. You can create as many as you need, using different voice providers and configurations for different use cases.

Voice Provider

The AI engine that powers the voice conversation. BuildVoiceAI supports three providers:

Retell AI — Known for natural-sounding voices and strong knowledge base support. Supports file, URL, and text knowledge sources.
Vapi — Offers the widest selection of underlying voice engines (ElevenLabs, OpenAI, PlayHT, Deepgram, Azure, and more). Highly configurable.
Bland.ai — Simple API with competitive pricing and fast setup.

You can connect multiple providers to your agency and use different providers for different agents. Each provider has its own API key, voice catalog, and billing.

Knowledge Base

A collection of reference material that an agent can access during calls to provide accurate, specific answers. Instead of relying solely on the prompt, the agent can search the knowledge base in real time.

Knowledge bases support three source types (availability varies by provider):

File — Upload PDFs, Word docs, CSVs, and other document formats.
URL — Provide a web page URL and BuildVoiceAI scrapes its content.
Text — Paste raw text directly, such as FAQs or product details.

This is useful when the agent needs access to information too detailed or frequently changing to include in the prompt itself.

Workflow

An automated sequence of actions that runs after a call ends. Workflows let you define what happens when certain conditions are met — for example:

Update a contact in your CRM after every call
Send a Slack notification when a caller books an appointment
Create a follow-up task when a lead is qualified

Workflows consist of a trigger (a call ends), optional conditions (call duration, sentiment, specific phrases), and actions (CRM update, notification, calendar booking, etc.).

An embeddable voice call interface you can add to any website. When a visitor clicks the widget button, it opens a voice call with your agent directly in their browser — no phone number needed.

Widgets are customizable with your brand colors, positioning, greeting message, and avatar. You embed them using a simple code snippet (iframe or script tag).

Portal

A white-label dashboard that your clients log into to view their own agents, call history, and analytics. The portal is fully branded with your agency’s name, logo, and colors — your clients never see the BuildVoiceAI brand.

Portal users have limited permissions. They can view their assigned agents and calls but cannot modify agency-level settings or access other clients’ data.

Phone Number

A telephone number from your voice provider that you assign to an agent. Phone numbers serve two purposes:

Inbound calls — When someone dials the number, the call is answered by the assigned agent.
Outbound calls — When the agent makes a call, this number appears as the caller ID.

Each phone number can be assigned to only one agent at a time. Numbers are purchased and managed through your voice provider’s dashboard, then synced into BuildVoiceAI.

Integrations

External services connected to your BuildVoiceAI account that extend what your agents and workflows can do:

GoHighLevel (GHL) — CRM integration for contact management, appointment booking, and pipeline updates.
HubSpot — CRM integration for contacts, deals, notes, and meetings.
Google Calendar — Check availability and book appointments on your calendar.
Calendly — Book meetings through your Calendly scheduling links.
Slack — Send call notifications and summaries to Slack channels.

Call

A voice conversation between a caller and an agent. Calls can be:

Inbound — Someone calls the agent’s phone number or uses a website widget.
Outbound — The agent calls a contact’s phone number (triggered manually or through a workflow).
Test — A browser-based call you make to test the agent (uses WebRTC, not a phone number).

Each call generates a recording, transcript, duration, and status. Calls are the primary unit of activity and billing in the platform.