Voice Agent Builder

The Voice Agent Builder is a visual, graph-based editor for designing what your voice agent says and does during a call. Instead of writing one giant prompt, you break the conversation into nodes (stages of the conversation) connected by pathways (the routes the LLM can take between stages, based on how the conversation is going). You can create a new agent from the dashboard. Describe whether you need an “Inbound” or “Outbound” agent and your use case — this is sent to an LLM to generate a starting workflow with default prompts and pathways, which you can then edit.

The graph model

A workflow is a directed graph:

Nodes represent a stage of the conversation or an action (e.g. greet the caller, collect an address, transfer the call).
Pathways (edges) connect nodes and represent the routes the LLM can take depending on what the caller says. The LLM decides at runtime which pathway to follow.

A workflow should have only one Start Call node and typically ends at an End Call node, with Agent nodes and other node types in between. See Editing a Workflow for how nodes, pathways, and node-level toggles fit together.

Node types

Node	What it does
Start Call	Starts the call and configures the agent’s greeting. Should have only one per workflow.
Agent	Holds the prompt that drives conversation at a given stage; connects to other nodes via pathways.
Global	Common instructions (tone, objection handling) appended to every node with “Add Global Prompt” enabled.
QA	Runs automated post-call quality analysis against criteria you define.
API Trigger	Exposes an endpoint so external systems (n8n, Zapier, your backend) can start outbound calls.
End Call	Configures the agent’s final message before the call is terminated. Should have only one per workflow.
Webhook	Sends call results to an external system (CRM, Zapier, n8n) when a run ends.

Beyond nodes, you can extend an agent with:

Tools — let the LLM call external APIs, transfer calls, or invoke MCP servers mid-conversation.
Knowledge Base — attach documents the agent can reference during a call.
Pre-Call Data Fetch — enrich context with an HTTP call before the agent starts speaking.
Pre-recorded Audio — mix in real recordings alongside LLM-generated speech.
Template Variables — reference initial_context and gathered_context values in prompts and payloads.

Where to start

New to EESI? Follow Editing a Workflow to learn the fundamentals of nodes and pathways.
Want to test immediately? Use a Web Call from the agent editor — no telephony setup required.
Ready to go live? Configure a telephony provider and add an API Trigger or set up inbound routing.
Need the call to hit your systems? Add a Webhook node to sync results to your CRM or automation tool.
Want to embed the agent on a website? See Add to Website.

Getting started

Core Concepts

Configurations