> ## Documentation Index
> Fetch the complete documentation index at: https://docs.getbutter.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Prompting for Voice

> Writing system prompts that sound natural

Writing for voice agents is fundamentally different from writing for text chatbots. In a voice conversation, the user cannot "scan" the text; they must listen linearly. Long, complex sentences increase cognitive load and latency.

## 1. Be Concise

**Bad:**

> "Thank you for calling Acme Corp, the leading provider of widgets in the tri-state area. I understand you are calling about an order status. I can certainly help you with that today. Could you please provide your order number?"

**Why it fails:**

* Takes 10 seconds to say.
* The user forgets the question by the end.
* Increases latency (more tokens to generate).

**Good:**

> "Thanks for calling Acme. I can help with your order. What's the order number?"

**Tip:** Add `Keep your responses short and conversational, ideally under 20 words.` to your system prompt.

## 2. Avoid Special Characters

LLMs sometimes output markdown, lists, or URLs. These sound terrible when read by TTS.

**Instruction:**

> "Do not use markdown, bullet points, or emojis. Do not read out URLs; instead say 'check our website'."

## 3. Handle Interruptions

Users *will* interrupt. Design your prompt to handle context switching gracefully.

**Instruction:**

> "If the user interrupts or changes the topic, stop what you are saying and address their new point immediately."

## 4. Pacing and Fillers

To make the agent sound more human, you can instruct it to use fillers, but use them sparingly.

**Instruction:**

> "Use natural fillers like 'hmm' or 'let me check' only when retrieving data via a tool."

## 5. Phone Number Formatting

TTS engines sometimes read phone numbers as "one million..." instead of "one, zero, zero...".

**Instruction:**

> "When speaking phone numbers, say them digit by digit, grouping them for clarity (e.g., 555-123-4567)."