# Buy the number, route the call, keep the recording.

Native telephony on a Telnyx voice stack. Search and buy numbers in the dashboard, point them at agents, and get transfers, hold music, recordings, and per-call cost from the same platform that runs the conversation.

## What it does

### Buy and manage numbers in-app

Search Telnyx inventory for US local or toll-free numbers by area code or city and buy without leaving the dashboard. Pick the agent that answers at purchase time. Each number carries its caller ID name, capabilities, and reputation status in one table.

- Search by area code, city, or toll-free
- Pick the answering agent at purchase
- Reputation status tracked per number
- Assign, pool, or archive from one table

### Bring your own numbers over SIP

Keep numbers you already own. The platform provisions a TLS SIP trunk on Telnyx for each imported number, with SRTP as an explicit opt-in, and rolls back cleanly if provisioning fails. Imported and purchased numbers sit in the same table and route to agents the same way.

- TLS SIP trunk provisioned automatically
- SRTP is an explicit opt-in per trunk
- Failed provisioning rolls back cleanly

### Transfers that survive real phone lines

Cold transfer hands the caller straight to the destination number. Warm transfer holds the caller on hold music, dials the human, confirms a live person, gives a private briefing, then bridges. Failed targets hunt an ordered fallback list and the flow branches on the real outcome.

- Ordered fallback destinations per transfer
- Private briefing to the human before the bridge
- Machine detection screens the agent leg
- Stale holds swept by a per-minute cron

### Every call recorded, transcribed, logged

Inbound recording is switched on per number at provisioning. After each call, the post-call webhook writes the recording, transcript, duration, end reason, sentiment, and itemized cost to one call row, and Call Center history makes the log searchable by number, direction, and status.

- Recording, transcript, and cost on one call row
- Search history by number, direction, status
- Sentiment and end reason per call

### A voice stack you can tune per agent

Every agent is provisioned as its own Telnyx voice agent. Pick the voice, greeting behavior, background audio, barge-in timing, noise suppression engine, and one of 7 transcription models. Duration and silence limits are clamped server-side so a bad setting cannot strand a call.

- Choose from 7 transcription models
- Krisp or DeepFilterNet noise suppression
- Voicemail detection can leave a message
- Hold music uploads with inline preview

### Outbound dialing with guardrails

The dial core normalizes numbers to E.164, refuses self-calls, runs premium machine detection, and stamps contact variables into every call before dialing. The API gates each dial on contact DND, your blacklist, and wallet balance. Caller ID is drawn from your number pool per dial.

- DND, blacklist, and wallet checks first
- Premium machine detection on every dial
- Caller ID drawn from a number pool per dial
- Self-call guard blocks dialing itself

## Under the hood

- **ENGINE:** Telnyx voice stack; each agent provisioned as its own voice agent with per-call webhooks
- **NUMBERS:** US local and toll-free search by area code or city; purchase, assignment, and archive in-app
- **SIP:** Bring-your-own numbers over a TLS FQDN trunk; SRTP opt-in; rollback on failed provisioning
- **TRANSFERS:** Warm and cold with hold music, private briefing, machine detection, and ordered fallbacks
- **RECORDINGS:** Inbound recording enabled per number at provisioning; mp3 stored on the call row with the transcript
- **STT:** 7 transcription models: Deepgram Flux and Nova, Azure Fast, AssemblyAI, Grok, Distil-Whisper
- **PRICING:** $0.07 per minute voice, metered per call with an itemized cost breakdown

## FAQ

**Do I need my own Telnyx or Twilio account?**

No. Numbers are searched, purchased, and provisioned on Assistable's Telnyx stack from inside the dashboard. If you already own numbers elsewhere, import them: the platform provisions a TLS SIP trunk for each one, and they route to agents exactly like purchased numbers.

**How does inbound routing work?**

Each agent is provisioned as its own Telnyx voice agent with a telephony application. Buying or assigning a number points the number's connection at that application, so inbound calls land directly on the AI. First-time callers get a contact record created automatically from the inbound call.

**What happens when a transfer target does not answer?**

Machine detection distinguishes a live person from voicemail on the agent leg. On voicemail or no answer, the engine hunts the next destination in your ordered fallback list while the caller stays on hold music. A cron job sweeps every minute so a stalled hold is force-resolved instead of leaving a caller in silence.

**What does voice cost?**

Voice is $0.07 per minute, metered at the end of each call with an itemized cost breakdown stored on the call row. Dials are gated on your wallet balance, and signup is free pay as you go.

**Which numbers can I buy or bring?**

The purchase dialog searches US local and toll-free inventory by area code or city. The search API also accepts other country codes plus national and mobile number types. Imported numbers connect over a TLS SIP trunk between your carrier and the platform's Telnyx stack.

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Source: https://www.assistable.ai/platform/telephony