> ## Documentation Index
> Fetch the complete documentation index at: https://docs.dialtu.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Voice, call and AI features
> Language, voice, silence, voicemail, and what the agent extracts after a call
Everything that defines **how the agent sounds** and **how it behaves** during and after the call.
## Language and voice
**📷 Screenshot needed** — the Voice Configuration group expanded, with language, voice and the three advanced sliders.
Save to `/images/en/voice-agents/configure-voice.png`
### Language
Four options: **English**, **Spanish (Latin America)**, **Spanish (Spain)** and **Multilingual**.
Changing the language **clears the selected voice**, because voices are filtered by language. Always pick the language first.
**Multilingual** lets the agent switch language to match the caller. Use it only if you need it — an agent with a fixed language usually sounds more consistent.
### The voice
The list is filtered by the chosen language, and each card shows the gender and lets you play a sample.
**Premium voices aren't marked in this selector.** Some voices cost an extra **2.5 credits per minute**, but that only shows in the **Voices** module, not here. If cost matters, check the voice there before assigning it.
The price in the top bar **does** include the surcharge, but without breaking it out.
### Advanced controls
Three sliders, all defaulting to **1.0**:
| Control | Range | What it does |
| --------------------- | ------- | ----------------------------------------------------------- |
| **Voice Temperature** | 0 – 2 | Stability. Lower = more consistent; higher = more variation |
| **Voice Speed** | 0.5 – 2 | Rate of speech |
| **Volume** | 0 – 2 | Output level |
For business calls, nudging the speed down (0.9) usually improves comprehension, especially for numbers and addresses.
## Communication: number and schedule
### The number
Chosen in the **Communication** group. One agent can hold several numbers, and one number can serve several agents.
### Inbound agent
Turn on **Inbound Agent** for it to receive calls. Doing so **clears the selected number** and reloads the list, because the eligible numbers change.
### Time-based routing
Inbound agents only. Defines the windows it covers, with up to **4 ranges per day**.
| Concept | What it means |
| ----------------- | --------------------------------------------------------------------------------------------------------- |
| **Quick presets** | Morning, Business, Evening, After Hours. They **replace** the current schedule |
| **Timezone** | Ranges are evaluated in this timezone, not the customer's |
| **Default agent** | Handles whatever no other agent covers. Ticking it **clears its schedule** |
| **Conflicts** | If your range clashes with another agent on the same number, the editor warns you and **blocks the save** |
If a number has **no default agent**, calls outside scheduled hours **aren't routed to anyone**. The editor warns you but still lets you save.
**A paused agent takes no calls**, not even as the number's default agent.
**📷 Screenshot needed** — the time-based routing modal with several ranges configured.
Save to `/images/en/voice-agents/configure-schedule.png`
## Speech & Call
The fourth settings group.
| Setting | Default | What it does |
| -------------------------- | ------- | ---------------------------------------------------------------------- |
| **Normalize for Speech** | Off | Reads numbers and dates in spoken form ("twenty-five" instead of "25") |
| **End Call After Silence** | 600 s | Hangs up after that much caller silence. **Minimum 10 s** |
| **Voicemail detection** | Off | Detects an answering machine and decides what to do |
Turning on voicemail detection lets you pick an **action**:
* **Leave Static Message** — a fixed text you write.
* **Generate from Prompt** — the AI drafts the message from your instruction.
* **Hang Up** — disconnects without leaving anything.
The helper text on these toggles **disappears once you turn them on**. If you need to re-read what one does, switch it off for a moment.
## AI Features
The **AI Features** button in the top bar. This is what the agent does **after** hanging up.
**📷 Screenshot needed** — the AI Features modal with its three sections.
Save to `/images/en/voice-agents/configure-ai-features.png`
### Transcription
| Mode | When to use it |
| ------------------ | -------------------------------------------------- |
| **Fast** (default) | Real-time conversations where latency matters most |
| **Accurate** | When critical data has to be captured exactly |
The other two features depend on the quality of this transcription.
### AI client auto-creation
Off by default. When enabled, it extracts data from the call and **creates the contact record**.
* **Sources**: transcript (on), request variables (on), call metadata (off).
* **Fields**: phone always; first and last name on; email and company off.
* **Tags**: you can apply tags to created contacts, and optionally to updated ones.
* **Advanced**: a custom extraction prompt, and permission to update existing contacts.
### AI follow-up detection
Off by default. Analyses the call and flags whether it **needs follow-up**.
It requires a **detection prompt** describing what conditions justify one. You can include the disposition tag in the analysis and set a retry threshold.
## Disposition tags
The fifth settings group. These are the categories each call is classified into when it ends — *Interested*, *No answer*, *Call back* — and they're classified by **Dialtu's own AI**, not the provider's.
* They are **account-wide templates**: creating or editing one affects every agent, and they save instantly, without waiting for you to save the agent.
* Each has a **type**: `Standard`, `Retry` or `No Answer`.
* The **Analysis Prompt** (max 500 characters) is optional but **significantly improves accuracy**: describe when the tag applies.
* A tag can be marked as the **default for not-connected calls**, and there can only be one per type.
## Next step
Give the agent real actions during the call.