Understanding Prompts

Your Secret Ingredient for Better Results

You don't need to be a tech expert to get the most out of Lafai. This guide explains everything in plain language.

What is a Prompt?

Think of a prompt like placing an order at a restaurant. When you tell the waiter what you want, how you want it cooked, and what you're allergic to — that's a prompt. It's simply a set of instructions.

A prompt is the instruction you give the AI so it knows what to look for and how to answer.

Without a prompt, the AI wouldn't know if you want a quick summary, a deep dive into every ingredient, or an analysis of pet food.

Why Does Lafai Use Prompts?

Lafai uses advanced AI (Google Gemini) to analyze your food. The AI is incredibly powerful, but it needs clear instructions to give you the right answer.

Different people have different needs. A parent checking snacks for their kids needs different information than someone tracking sodium for heart health. The same if you are a runner, pet owner, or simply wanting to lose some weight.

The prompt is what makes Lafai's analysis personal and relevant to you.

The Built-In Prompts — Ready to Use

Lafai comes with 7 carefully designed prompts so you can start scanning immediately.

🔬 General Ingredient Check — The all-rounder. Gives you a full breakdown of ingredients, nutrition, and whether the product is a good fit for you.
⚡ Quick Score — In a hurry? Get a green/amber/red traffic-light score and one key takeaway.
🧪 Additive Safety Check — Worried about E-numbers, preservatives, or artificial colors? This one digs into additives specifically.
🍽️ Meal Completeness — Is this enough for lunch? Find out if a product is a complete meal or what to pair it with.
📖 Ingredient Deep Dive — Explains every single ingredient in simple words — what it is, why it's there, and if it's safe.
🍎 Unlabeled Food Analysis — No label? No problem. Point your camera at a fruit, a cooked meal, or any food and get an analysis.
🐾 Pet Food Analysis — Scan your pet's food to check ingredient quality and safety for cats, dogs, and other animals.

How to Create Your Own Prompt

You don't need any technical knowledge. If you can describe what you want to know about a food product, you can write a prompt.

Step 1: Open the Prompts tab in the app
Step 2: Tap the + button to create a new prompt
Step 3: Give your prompt a name (e.g., "My Low-Sugar Check")
Step 4: Write what you want the AI to look for (in your own words, in any language)
Step 5: Save and start scanning!

Tips for writing good prompts:

Be specific: "Tell me about sugar and sodium levels" works better than "Analyze this".
Ask for what matters to you: "Is this suitable for someone with high blood pressure?"
Use your language: You can write in any language — the AI will respond in the same language.

Examples of Custom Prompts

Prompts can be as simple or as complex as you need them to be. A complex prompt gives the AI a specific structure and format to follow, similar to our built-in prompts. Below are two examples of complex custom prompts:

📋 Restaurant Menu Analysis

"Analyze these menu images and for each dish from the menu, list the following: 1. 📊 Key nutritional data estimated from each item's name (calories, fat, sodium, sugar, protein, fiber) 2. 🚦 A score for each item on the menu: GREEN (very suitable), YELLOW (ok in moderation), RED (limit consumption) 3. 📝 An explanatory sentence 4. 👤 A sentence about how the product fits the user's lifestyle profile"

🌱 Vegan Ingredient Scan

"I'm vegan. Please analyze the product and explain every single ingredient in simple words: 1. 🌿 What it is and if it's 100% plant-based 2. 🕵️ Why it is there 3. ⚠️ Flag any hidden animal-derived ingredients (e.g., casein, whey, gelatin, carmine) Also note if it's certified vegan."

Short Prompts & Lifestyle Profile

You can also create short, simple prompts. These can be used as stand-alone prompts, integrated into another complex prompt, or even pasted directly into your Lifestyle Profile in the app:

👶 Baby Food Check

"I'm shopping for my baby (12 months old). Check if this food is age-appropriate. Flag any added sugars, salt, honey, or allergens. Tell me if the portion size is suitable for a toddler. I agree this is just for my own quick reference info, and for any serious concern I will contact a suitable professional."

💪 Gym & Protein Focus

"I go to the gym 4 times a week. I need high protein, low sugar products. Tell me the protein-to-calorie ratio and whether this is a good post-workout snack."

🫀 Heart-Healthy Check

"I have high blood pressure. Focus on sodium, saturated fat, and cholesterol levels. Flag anything that exceeds recommended daily limits for heart health. I agree this is just for my own quick reference info, and for any serious concern I will contact a suitable professional."

How to Copy and Adapt an Existing Prompt

Copy a built-in prompt: Built-in prompts cannot be edited directly (they're maintained by the app), but you can use them as inspiration to create a new one with your own twist.
Duplicate a custom prompt: Tap on any prompt → copy its text → create a new prompt → paste and modify to fit your needs.
Adapting tips: Change the focus area, add your personal dietary restrictions, switch the language, or combine ideas from multiple prompts.