G2
Voted 4.9

AI voice agent development

AgentVoice builds custom AI voice agents on Vapi, Retell, ElevenLabs, Bland, Synthflow or our own engine in your cloud. Our team writes the call flows, connects your systems and tunes the agent on real calls until it performs.

Custom build

We turn the way your team handles calls into a working voice agent. We design the prompts and call logic, connect your CRM, calendar and phone system, and set the voice to match your brand.

  • Prompt and call flow design
  • CRM, calendar and workflow integrations
  • Voice and persona set to your brand
  • Workflow mapping and QA
  • Deployment handled by our team
Contact sales
Optimization

Already running an agent on Vapi, Retell or another platform? Over a focused four-week engagement we review live calls, find where the agent struggles and tune its prompts, flows and integrations until it holds up.

  • Working sessions with our team
  • Call monitoring and review
  • Prompt and response tuning
  • Slack, email and call support
  • Training so your team can own it
Contact sales

How an AI voice agent build works

Scoping call

We learn how calls come in today, what callers ask for and what your team does next. That becomes the spec for the agent and the basis of the quote.

Choosing the platform

We recommend where the agent should run based on your call volume, the systems it has to reach and your data requirements. If you already use Vapi, Retell or ElevenLabs, we can build there.

Building the agent

We write the prompts and call flows, set up the voice, and connect the tools the agent uses during the call, like calendar booking, CRM lookups and live transfers.

Testing on real calls

Before launch we run the agent through the calls your team takes every day, plus the unusual ones that trip people up, and fix what breaks.

Launch and tuning

After launch we review transcripts, adjust prompts and flows, and report on the outcomes you care about, such as bookings, transfers and qualified leads.

The platforms we build on

We build on the platform you want. If your team already has a Vapi, Retell, ElevenLabs, Bland or Synthflow account, we build the agent there and you keep full access to it. If you haven’t picked one, we recommend a platform after the scoping call based on your call volume, the systems the agent has to reach and how much control you need over call data. Our pages on Vapi, Retell, Bland and Synthflow explain when we’d choose each one.

ElevenLabs is part of our builds on every platform that supports its voices, and we build on ElevenLabs Agents directly when it fits the job. For teams that need everything inside their own infrastructure, we deploy the AgentVoice engine into your Azure or AWS account or onto your own servers under the platform license, with the source code included.

Voice agents we build

Every agent starts from a specific set of calls. These are the kinds AgentVoice builds, and each one can connect to the systems your team already uses.

AI voice agent development FAQ

How does pricing and scope work?

We scope each project on a call. We look at the call flows, the systems the agent connects to and any data cleanup or infrastructure work, then quote the build and any ongoing optimization. Usage on a voice platform like Vapi or Retell is billed to your account with that platform, and usage on the AgentVoice engine is billed at cost. The pricing page has more detail.

How long does a custom build take?

A custom build usually takes 7–10 days once we have access to your tools and a clear picture of the calls the agent will handle. The four-week optimization follows, and during it we watch the agent on real calls and refine its behavior week by week.

What systems can you connect the agent to?

CRMs, calendars, email, help desks, phone systems and internal databases. If you have a custom API or an unusual setup, we scope it on the first call and include it in the timeline.

Can you fix an agent we already built?

Yes. The optimization engagement is designed for that. We review your agent’s calls on Vapi, Retell, ElevenLabs or wherever it runs, find where it fails, and fix the prompts, flows and integrations behind those failures.

How do you keep performance high?

During optimization we monitor real calls, adjust prompts and flows, and track outcomes such as connection rates, bookings and qualified leads. Response time depends on the platform and the models behind the agent, so we choose and configure both with latency in mind.

Do you build for complex workflows or enterprise teams?

Yes. We build multi-department call flows, high-volume queues, advanced routing and real-time sync with internal systems. When call data has to stay inside your own infrastructure, the agent can run on the AgentVoice engine deployed to your cloud under the platform license.

Why hire a team to build the agent?

A demo agent can come together in an afternoon. An agent that handles real callers reliably needs integration work, testing against the calls your team takes and weeks of tuning after launch. We do that work for you, and your team skips the trial and error.