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Connect your application to telephony

European telephony infrastructure for your AI agent

Add telephone calls to your application through Seamly’s Voice API. Keep control of your conversation logic and choose whether your application exchanges real-time audio or text.

Explore Voice API Experience the platform

Add telephony without making it your team’s speciality

Your application already contains the intelligence, workflows and customer experience. Connecting it to telephone calls introduces a different technical layer, from numbers and SIP to real-time media and voice processing. Seamly provides the telephony infrastructure and APIs your team needs to make that connection.

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Built by developers, for developers

Seamly is designed around how technical teams work. Clear APIs, direct access to documentation and support and control over your own application let you integrate, test and manage voice.

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Know what voice will cost

Voice infrastructure can introduce multiple charging units and additional platform fees. Seamly uses clear, predictable pricing without licence or setup fees, so costs are easier to forecast as usage grows.

Keep your infrastructure European

Seamly operates and hosts its services in the EU, giving teams with an EU-first strategy more control over where their voice infrastructure and data are handled.

Built around your application

Choose how your application connects to voice

The Voice API connects incoming telephone calls to your application. For every call, your application determines whether Seamly exchanges text or audio.

01. Connect your endpoint

When a call arrives, Seamly sends an authenticated request to your application’s endpoint. Your response specifies the secure WebSocket URL and whether to exchange text or audio for that call.
02. Choose Text-to-voice or Voice-to-voice

Use Text-to-voice when your application works with text. Seamly handles STT, TTS, barge-in and the telephone connection. Use Voice-to-voice when your application already processes real-time audio. Your application sends and receives bidirectional audio over WebSocket and handles voice processing. Seamly handles the telephone connection.
03. Keep your conversation logic

Your application determines what happens during the conversation. You keep control of your AI, logic and customer experience.
04. Manage and scale through our APIs

Configure projects and telephone numbers programmatically, and retrieve call data for your own analytics and dashboards.

Predictable pricing as usage grows

Voice costs should be predictable before the invoice arrives. Seamly keeps its charging model transparent, so you can forecast your infrastructure costs and incorporate voice into your own pricing.

Component	Costs
License fee	None
Setup fee	None
Text-to-voice	Clear pay-as-you-go charging
Voice-to-voice	Clear pay-as-you-go charging
Analytics API	Included
Audio recordings	Included
Telephone numbers	Available through Seamly
Concurrent calls	Unlimited