Sysevo
Voice AI Platform

Voice AI thatsounds human.

Build and deploy voice agents that handle real conversations. Inbound, outbound, and everything between.

Agents live · answering calls now
Hear it for yourself ↓Build your first agent

1M+ minutes processed · Trusted by teams worldwide · 60+ languages

Live, right now

See an agent handle real calls.

A live conversation on the left, the agent's console on the right.

Live Call, 00:23

Caller Memory

VIP guestBooth seating3rd visit
S

Hotel Concierge

Active · Inbound

3

Active calls

247

Today

1:47

Avg

99.2%

Ans.

84

Booked

Booking rate0%

Live activity

Table for 4 · Sat 7:30pm · Confirmed

Suite booked · Fri–Sun · Room 412

Wake-up call · 6:45am · Room 308

Airport taxi arranged · 7:30am

Spa treatment · Sunday 2pm · Done

Live demo

Talk to a live AI agent.

Pick an agent type and call. No signup, no download.

Call Alex

Hotel Concierge

Browser-based · No account needed · Free

No account needed · Works in your browser · Free to try

Capabilities

Everything a phone agent needs.

Inbound and outbound, with memory, tool calling, and multi-language support built in. Not a chatbot on a phone line — a real AI agent built for voice.

Build your first agent

Inbound calls

Never miss a customer call. Your agent answers instantly, 24/7, in any language.

Outbound campaigns

Upload a contact list. Your agent calls everyone. You review results in real time.

Voice cloning

Train a custom voice that sounds like your brand — or a specific team member.

60+ languages

Serve customers worldwide without hiring multilingual staff.

Unique

Caller memory

Every returning caller is recognised by phone number. Name, history, and preferences — surfaced before they speak.

Low latency

Under 800ms to first word. Natural, human-paced conversation. No awkward pauses.

Tool calling

Book appointments, update records, check availability — in real-time during the call.

Human escalation

When the agent can't help, it transfers seamlessly. The caller never knows they were on hold.

The Agent Editor

Every detail of your agent, in one place.

Configure voice, personality, memory, tools, and AI model without writing a single line of code.

Tools & Integrations

Your agent takes action. During the call.

Eight tools — five active by default, three advanced — let your agent book, look up, transfer, send, and respond — without any human intervention. Connect your existing CRM, calendar, and communication tools in minutes.

CRM

HubSpotSalesforcePipedriveZohoCloseMonday

Calendar

Google CalendarOutlookCalendlyAcuity

Messaging

Twilio SMSSendgridMailchimpPostmark
Calendar BookingBuilt-in

Google Calendar, Outlook, Calendly, or custom API. Agent checks availability and books in real time during the call.

CRM LookupBuilt-in

Pull the caller record from HubSpot, Salesforce, Pipedrive, or any API — before they say a word.

Knowledge BaseBuilt-in

Semantic search across your PDFs, docs, and web pages. Agent answers questions directly from your content.

Call TransferBuilt-in

Transfer to a human agent or number. Set trigger conditions in natural language. Caller stays on the line.

Send SMSBuilt-in

Send confirmation, links, or follow-ups during or after the call. Fully templated with caller variables.

Send EmailAdvanced

Post-call email to the caller, an internal address, or both. Triggered automatically on call end or custom conditions.

Webhook / API CallAdvanced

Call any external endpoint mid-conversation. Pass caller data and use the response to continue the call.

Custom FunctionAdvanced

Write a JavaScript function that runs during the call. Full access to call state, transcript, and memory.

Workflow Editor

Program complex call logic — visually.

Not every call is simple. Branch on caller intent, route by customer type, fire tools in sequence.

Live preview: a vet practice call routing through memory lookup, CRM retrieval, appointment booking, and SMS confirmation.

Caller Memory

Your agents don't forget.

Every caller is recognised by their phone number. No accounts, no logins. Just instant, personal service from the first word.

See how Caller Memory works →
Riverside Vets · NadiaFirst call
S
Riverside Vets, you're through to Nadia. Who am I speaking with?
Hi, it's Ben Walsh.
S
Hi Ben! How can I help you today?
I need to get my dog booked in for his annual vaccination.
S
Of course. What breed is he, and how old?
He's a 4-year-old Labrador, his name's Milo.

Agent stores: caller name, pet name & breed, reason for visit.

Riverside Vets · Nadia3 weeks later · Returning caller
Memory surfaced · Ben Walsh · 3 weeks since last call
Milo (Labrador, 4y)Annual vaccinationPrefers mornings
S
Ben, calling about Milo's vaccination follow-up by any chance?
Spot on, yeah.
S
I've got a morning slot with Dr. Collins this Thursday at 10am. Shall I lock that in?
Thursday 10am is perfect.
S
Done. I'll send a text reminder to your mobile shortly.

Zero re-introduction. Full context carried forward from call one.

Recognised by

Phone number

No login required from the caller

Memory survives

Agent updates

Remembers even if you rebuild the agent

GDPR

Deletion on request

Verbal or API-triggered deletion

Across every industry

Deployed across 12 industries.

Hospitality

Hotel Concierge

94%
Call resolution rate
24/7
Always available

"Aria handles 94% of all inbound calls. Reservations, room service, concierge — all resolved without staff involvement."

Table bookingsRoom enquiriesLate check-outConcierge requests

Healthcare

Medical Receptionist

70%
Fewer missed appointments
3min
Average booking time

"Clara books appointments, handles prescription enquiries, and routes urgent calls — without a single dropped call."

Appointment bookingPrescription queriesUrgent call routingFollow-up reminders

Recruitment

Candidate Screener

40×
Faster candidate pipeline
0
Calls dropped or missed

"Marcus runs first-call screening 24/7. Qualified leads land in the CRM with structured notes before the hiring manager starts their day."

First-call screeningAvailability checksCRM captureQualification scoring

Real Estate

Lead Qualifier

3×
More viewings booked
< 1min
Lead response time

"Sam qualifies inbound enquiries, books viewings, and updates the CRM in real time — converting traffic while the team focuses on closing."

Enquiry qualificationViewing bookingsCRM updatesProperty questions

Hospitality · Healthcare · Recruitment · Real Estate · Financial Services · Retail · Legal · Logistics and more

Custom solutions

Powered by the best models.

All inference is managed for you — every provider included. No API keys, no surprise bills.

OpenAIOpenAI
GPT-4.1Recommended

Our recommended model

GPT-4.1 mini

Faster · Lower cost

o3

Advanced reasoning

AnthropicAnthropic
Claude 3 Opus

Most capable

Claude 3.7 SonnetRecommended

Best for nuanced conversation

Claude 3.5 Haiku

Faster · Excellent quality

GoogleGoogle
Gemini 2.5 ProRecommended

Best for multilingual calls

Gemini 2.5 Flash

Fast & highly capable

Gemini 2.0 Flash

Ultra-fast response times

xAI
Grok 3Recommended

Best-in-class reasoning

Grok 3 mini

Fast · Cost-efficient

Speech to Text

DeepgramNova-2 / Nova-3
AssemblyAIUniversal-2
WhisperWhisperLarge v3
AzureFast Transcription

Text to Speech

ElevenLabsElevenLabsTurbo v2.5
PlayHTPlayHT 3.0 Turbo
CartesiaSonic
AzureNeural voices

Telephony

Twilio
Vonage
Telnyx
Bandwidth
Plivo
SignalWire

Built for production

Enterprise-grade infrastructure.

< 800ms

First response

24/7

Always-on infrastructure

30+

Languages

∞

Concurrent calls

Speech-to-textDeepgram Nova-2 / Nova-3
Text-to-speechElevenLabs
LLM optionsGPT-4.1 · Claude 3.7 · Gemini 2.5 · Grok 3
TelephonyTwilio
Call recordingAll plans
TranscriptionAutomatic · Searchable
Caller memoryGrowth plan +
Tools8 tools, 5 active by default
WorkflowsVisual builder · Unlimited nodes

Call Intelligence

Every call. Automatically scored.

The moment a call ends, Sysevo grades it across five dimensions. No manual review, no spreadsheets — your quality data is ready before your team starts their day.

Resolution

Did the agent fully resolve the caller's intent — or leave it open?

Sentiment arc

Tracks how caller emotion shifts across the conversation, word by word.

Prompt adherence

Did the agent stay within its instructions, tone, and compliance constraints?

Response latency

Measures time from end of caller utterance to start of agent response.

Outcome tag

AI classifies every call: booked, resolved, escalated, callback, or lost.

Sarah Mitchell

+44 7700 900 142 · 2m 47s

Resolved

Call Score

94/100

Sentiment

9.1/10

Adherence

98%

Sentiment arc

↗ Improved

Auto-executed · post-call

Transcript indexed

6 key moments flagged

+0.3s

Sentiment scored

Positive · 9.1 / 10

+0.7s

CRM contact updated

Sarah Mitchell · status: resolved

+1.1s

Caller memory saved

3 preferences updated

+1.5s

AI summary written

47-word call summary

+2.0s

Follow-up queued

SMS confirmation scheduled

+2.6s
All 6 actions completed in 2.6s · Zero human involvement

Deployment

Four ways to deploy.
One platform.

Inbound

Answer every call, 24/7, without staff.

  1. 1Buy or port a phone number
  2. 2Assign your agent
  3. 3Go live instantly

Outbound

Reach hundreds of leads while you sleep.

  1. 1Upload your contact CSV
  2. 2Configure the campaign
  3. 3Review results in the CRM

Web Widget

Let website visitors talk to your agent.

  1. 1Copy one line of code
  2. 2Paste it in your website
  3. 3Live in seconds

API

Integrate voice into any workflow.

  1. 1Get your API key
  2. 2Call /v1/calls endpoint
  3. 3Full programmatic control

For developers

Full REST API.
Any LLM.

Build voice AI into any product. Use our REST API to start calls, process webhooks, and query call data — in any language or framework.

REST API + WebSocketsFull programmatic control
Custom LLM supportGPT-4.1, Claude, Gemini, Grok
Real-time webhooksEvents for every call state
< 800ms latencySub-second first response
Read the full API docs →

# Start an outbound call

curl -X POST https://api.sysevo.io/v1/calls \
  -H "Authorization: Bearer sk_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "agent_id": "agt_hotel_concierge",
    "to": "+447700900142",
    "metadata": { "booking_ref": "BK-8842" }
  }'

One platform

Everything included. Done for you.

LLM, speech recognition, voice synthesis and telephony. Your CRM, phone system and analytics, one connected system, built for you.

Book a demo →See how it works