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Introducing Line: The modern voice agent development platform

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Introducing Line: The modern voice agent development platform

Learn more

Line: The modern voice agent development platform

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The modern voice agent development platform

Line is a code-first ecosystem to get from zero—to your first agent—to your best agent, in record time.

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Ways to get started

Start from anywhere. We’ll meet you there

Bring your own code, start with a template, or even a prompt. Line meets you where you are and gets you live fast. All roads lead to a code file that’s written in the Line SDK, so you can use the ecosystem to iterate.

Get started

Bring-your-own reasoning

Bring the full complexity of your existing production-grade reasoning system or start anew.

Templates

Jumpstart a new voice agent with ready-made templates.

Text-to-Agent

Get to a v0 voice agent—with its code—through just a sentence.

Bring-your-own reasoning

Bring the full complexity of your existing production-grade reasoning system or start anew.

Using Line’s public SDK, you can quickly turn your knowledgeable text chatbot into a voice agent or start from a clean, easy foundation. Connect to any LLM system and tool call backends you want.

Templates

Jumpstart a new voice agent with ready-made templates.

Clone one of our templates, built on top of our SDK, and customize it to your use case, starting with outbound calling and inbound help desk.

Text-to-Agent

Get to a v0 voice agent—with its code—through just a sentence.

Generate a voice agent with our client. Write your own text prompt to spin up an agent that you can extend via the Line SDK.

Line overview

End-to-end—it’s one continuous Line of voice innovation

Line lets you build, deploy, and test enterprise-grade voice agents on a consolidated stack that’s fully owned, fully optimized.

Multi-prompt configuration

Move beyond simple prompt configurations, so you get the smartest agents on the market.

Tool calling for knowledge and action

Give your agent powers, including RAG capabilities for access to live knowledge that keeps your agent relevant and up-to-date.

Background agents

Coordinate background agents that can listen, analyze, and summarize your conversations—all while writing to background systems in parallel.

Build

Robust SDK

Our SDK is everything you need to build the most powerful, intelligent agents with taste. Get advanced reasoning, parallel background tasks, and real-time system actions—all with ultra-low latency.

Multi-prompt configuration

Move beyond simple prompt configurations, so you get the smartest agents on the market.

Tool calling for knowledge and action

Give your agent powers, including RAG capabilities for access to live knowledge that keeps your agent relevant and up-to-date.

Background agents

Coordinate background agents that can listen, analyze, and summarize your conversations—all while writing to background systems in parallel.

Build

Robust SDK

Our SDK is everything you need to build the most powerful, intelligent agents with taste. Get advanced reasoning, parallel background tasks, and real-time system actions—all with ultra-low latency.

Sonic text-to-speech

With time-to-first-audio under 90ms, Sonic reliably delivers realistic, fluid conversation that flows naturally. Sonic is the fastest model available on the market, affording ultra-low latency performance all around.

Ink speech-to-text

Of all streaming STT models, Ink has the lowest time-to-complete-transcript and is tested against real-world conditions including noisy backgrounds to deliver accurate transcriptions.

Models

Top notch in-house models

Our fully-owned voice stack is underpinned by our leading Ink STT and Sonic TTS models plus deployment so you can fine-tune, co-locate, and optimize for max performance.

Sonic text-to-speech

Ink speech-to-text

Of all streaming STT models, Ink has the lowest time-to-complete-transcript and is tested against real-world conditions including noisy backgrounds to deliver accurate transcriptions.

Models

Top notch in-house models

Our fully-owned voice stack is underpinned by our leading Ink STT and Sonic TTS models plus deployment so you can fine-tune, co-locate, and optimize for max performance.

Github integration

Get one-click deployment and scaling with Github integration in our reliable infrastructure.

CLI

Remain in your console when developing and run commands for a streamlined workflow.

Observability

View logs from your code for every call placed on Line.

Fast deployment

Talk to your agent in under 30 seconds.

Deploy

Fast deployment

The best agents are built via rapid, iterative development. Code → Deploy → Test. Repeat. Line is designed for rapid development loops.

Github integration

Get one-click deployment and scaling with Github integration in our reliable infrastructure.

CLI

Remain in your console when developing and run commands for a streamlined workflow.

Observability

View logs from your code for every call placed on Line.

Fast deployment

Talk to your agent in under 30 seconds.

Deploy

Fast deployment

The best agents are built via rapid, iterative development. Code → Deploy → Test. Repeat. Line is designed for rapid development loops.

System metrics

Review key metrics like call success and time-to-first-audio.

Call analytics

Use an LLM-as-a-judge to evaluate every Line call.

Live testing

Instantly call your agent on the phone or over the web for testing.

Test

Built-in evaluations

How do you know your voice agent is any good? We added a framework for live testing, system metrics, and custom call analytics.

System metrics

Review key metrics like call success and time-to-first-audio.

Call analytics

Use an LLM-as-a-judge to evaluate every Line call.

Live testing

Instantly call your agent on the phone or over the web for testing.

Test

Built-in evaluations

How do you know your voice agent is any good? We added a framework for live testing, system metrics, and custom call analytics.

Trust and security

Enterprise-ready with production-grade agents at scale

Deploy with trust

Reliable and always on

Get dependable uptime and priority support with custom SLAs.

Compliant and secure

SOC-2 Type 2, HIPAA, PCI Level 1 compliant, with support for SSO.

SOC 2 Type II

HIPAA

PCI Level 1

Flexible and private

Deploy flexibly to meet compliance, residency, and security needs:

Secure API

Managed in-VPC (on-prem)

For every industry

Build the most intelligent voice agents, custom-fit to your industry

Healthcare

Improve patient management, provide faster answers on benefits eligibility, and maintain HIPAA compliance.

Build Line voice agents to

Simplify patient requests

Streamline intake

Answer questions 24/7 on billing, claims, and benefits eligibility

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Finance

Reduce call center costs, modernize IVR systems, and maintain PCI compliance.

Build Line voice agents to

Help with wealth management

Automate FNOL and reduce paperwork

Handle inquiries 24/7 for banking, credit card, and loan accounts

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Hospitality

Generate more revenue, simplify operations, and improve guest satisfaction.

Build Line voice agents to

Automate booking

Streamline check-in

Improve customer service with AI-powered turndown service and wakeup calls

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Empower your business with voice AI

Get started

Ready to build?

Generate intelligent, fluid conversational agents for just $0.06/minute on any plan.

Read the docs

Real-time, multimodal intelligence for every device.

Models

Products

Resources

Company

Legal

Real-time, multimodal intelligence for every device.

Models

Products

Resources

Company

Legal

Real-time, multimodal intelligence for every device.

Models

Products

Resources

Company

Legal