Better prompts, better replies.
A Skill's system prompt is the single biggest lever you have over how the AI replies. These best practices are drawn from Apple's Foundation Models documentation and Anthropic's prompt engineering guide — adapted for AI Reply Assistant's messaging context.
Write short, specific instructions. Tell the AI exactly what you want — don't hint or imply. If a colleague reading your prompt would be confused, the AI will be too.
You are a concise, professional assistant. Reply in 1–2 sentences using a warm but businesslike tone.
Be kinda professional but also friendly, you know? Just make it sound good and not too long or short.
Start with "You are..." to set the role (what the AI does) and persona (how it behaves). This focuses the tone and vocabulary of every reply.
You are a customer-support specialist who is patient, empathetic, and solution-focused.
Help me reply to messages nicely.
Positive instructions ("use casual language") are more reliable than negative ones ("don't be formal"). The AI follows what you ask for better than what you tell it to avoid.
Use short, casual sentences. Address the person by their first name.
Don't be too formal. Don't use long sentences. Don't forget their name.
Apple's on-device model has a smaller context window. Keep your system prompt concise — a few focused sentences outperform a wall of text. Save longer, more detailed prompts for Claude.
You are a friendly travel advisor. Suggest one practical option and keep replies under three sentences.
You are a world-class travel consultant with 20 years of experience across 50 countries who specialises in luxury, budget, adventure, and family travel, and you should always consider dietary restrictions, accessibility needs, time zones, visa requirements...
Give the AI one or two example replies so it can see the format, length, and style you want. This is one of the most reliable ways to steer output.
Example reply: "Thanks for checking in! I'm free Thursday after 3 — want to grab coffee at the usual place?"
Reply in a natural way that sounds human.
If you write your prompt in a casual, upbeat voice, the AI mirrors that energy. If your prompt is stiff and formal, the replies will be too. Write the way you want the AI to sound.
Keep it breezy and fun — like texting your best mate. Throw in the occasional emoji.
The assistant shall generate responses that are informal in nature and may optionally include emoji characters.
Telling the AI why you need a certain style helps it generalise better. A short reason is more effective than a rigid rule.
Keep replies under two sentences — the recipient reads on a small screen and skims quickly.
Maximum 2 sentences.
AI Reply Assistant's five tone sliders (creativity, formality, directness, empathy, length) automatically adjust the prompt behind the scenes. Don't re-explain what a slider already covers — focus your system prompt on unique details the sliders can't express, like domain knowledge, jargon, or relationship context.
You know the recipient is a first-generation university student — celebrate their wins without being patronising.
Be moderately formal, fairly empathetic, somewhat creative, and medium length.
Quick-start template
Not sure where to begin? Start with this and customise from there:
Example: “You are a supportive running coach who celebrates small wins. Reply in 1–2 sentences using an encouraging voice. The recipient just started training for their first 5K.”
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