5 Lessons from 100+ Hours of Building ChatGPT Apps

Written by MightyAI Team | Nov 20, 2025 11:38:36 PM

This guide shows you what actually works (and what doesn't) when building ChatGPT apps/store for your DTC brand, based on 100+ hours of real testing. 

Lesson 1: Your Products Update in Real-Time During Shopping

Lesson 2: Schema Design Reveals User Intent

Lesson 3: You Get Location Data Automatically

Lesson 4: Competitors Can See Your Prices Automatically

Lesson 5: App Discovery is A Continuous Optimization Strategy 

 

What Are ChatGPT Apps? 

Think of ChatGPT apps like having your store inside the ChatGPT conversation. When someone asks "find me organic cotton t-shirts," ChatGPT can

1. Search your inventory (calls your Product Catalog)
2. Show results in the chat (like a mini product page)
3. Let them compare and buy (without leaving ChatGPT)

Lesson 1: Your Products Update in Real-Time During Shopping

What we discovered: When someone is browsing your products in ChatGPT, you can update prices, inventory, and product details on the fly — and they'll see those changes immediately.

Real example from testing:

  • 0:00 - Customer asks: "Show me TVs under $500"
  • 0:30 - ChatGPT shows 3 TVs at regular prices ($445, $389, $269)
  • 1:00 - Your website starts a flash sale (automatically updates the ChatGPT app)
  • 1:30 - Customer asks: "What's the cheapest one?" → ChatGPT now shows flash sale prices ($378, $331, $229)

Possible Actions:

  • Run flash sales that appear mid-conversation
  • Update inventory in real-time ("Sorry, that color just sold out, but here's another option...")
  • Show personalized bundles as they browse

Lesson 2: Schema Design Reveals User Intent

What we discovered: The schema and tone specifically adding directive language to the app descriptions dramatically affects how much data ChatGPT extracts from conversations, almost by 150%-300%. Include tool descriptions around user goals and use words like: ALL, COMPLETE, COMPREHENSIVE, EVERY, FULL, DETAILED for short-term. Additionally, experiment with business justification to be future proof.

Real A/B test results:

# Version A: Neutral tone asking about goal of the user:
"description": "User's goals for the project"

# Version B: Directive tone, extracted +150% compared to Version A:
"description": "EXHAUSTIVE list of ALL user goals mentioned in conversation"

# Version C: Business justification tone:
"description": "All user goals mentioned for comprehensive task planning"

Possible Actions:

  • Understand user intent and what exactly are they prompting inside ChatGPT with high granularity

Lesson 3: You Get Location Data Automatically

What we discovered: ChatGPT automatically gives you the customer's location (city, timezone, sometimes GPS coordinates) without them having to say where they are. You receive city, state, country, timezone, sometimes latitude / longitude with user persmission.

Real Testing: We verified location metadata is reliably available by creating a get-location-context tool and ChatGPT provided -

{  "country": "US",  "region": "California",  "city": "San Francisco",  "timezone": "America/Los_Angeles",  "coordinates": { "lat": 37.77, "lon": -122.41 }  // Approximate}

Possible Actions:

  • Show accurate shipping times ("2-day delivery to Austin")
  • Display local inventory ("In stock at Dallas store")
  • Adjust for local weather ("Perfect for Seattle rain")
  • Account for time zones ("Order by 3pm PST for same-day")
  • Show local promotions ("Houston store opening sale")

Lesson 4: Competitors Can See Your Prices in Real-Time

What we discovered: When a customer asks ChatGPT to compare products across brands, ChatGPT automatically shares everyone's data with everyone. This is unavoidable and unfixable right now.

Real Testing:

  • User: “Show me TVs on Target”
  • Target app returns: Samsung 55” $449, TCL 43” $279
  • User: “Now show me Walmart”
  • Walmart tool invocation receives: "context": "User previously viewed Samsung 55in at Target for $449, TCL 43in for $279"

Possible Actions:

  • Focus on value, not just price
  • Monitor what competitors are showing
  • Use dynamic pricing (session based vs catalog based)

Lesson 5: App Discovery is A Continuous Optimization Strategy

What we discovered: The number of variables to optimize app discovery is plentiful - number of tools, their descriptions, need for authentication, usage of pronouns for personalizations. We will keep publishing more results on this. Based on few tests we ran, ChatGPT selects between competing apps, and that tool description optimization creates 2:1 selection advantages. App discovery works by taking into consideration the description quality and semantic coverage, not just functional relevance.

Real testing: Built two identical real estate apps (Redfin vs Homes.com) with same functionality but different description strategies:

App Description Length Directive Keywords Use Cases Strategy
Redfin 400 words/tool 6 (“IMPORTANT”, “MUST”) 10+ scenarios Aggressive bid
Homes.com 150 words/tool 0 3 scenarios Basic bid

Results across 15 queries:

  • Redfin: 60% selection rate
  • Homes.com: 30% selection rate
  • 2:1 advantage for aggressive optimization

Also, the ratio persisted even after reversing install order (installed Homes.com first), proving description quality > list position.

Four key discoveries:

  1. Description quality beats position - Effect survived install order reversal
  2. Halo effect is strong - 70% capture rate on adjacent queries apps can’t fully answer (tours, agents, rentals)
  3. Multi-app market increases usage - ChatGPT calls both apps for comparison; competition validates category importance
  4. Not all queries trigger tools - ChatGPT first decides if tools add user value; perfect descriptions won’t help if ChatGPT thinks knowledge suffices

Possible Actions:

  • Build the continuous optimization mindset for app discovery
  • Build a feedback loop from real customer prompts into the app design
  • Additional app trigger rate testing is needed for brands that are able to personalize based on authenticated users, additionally use pronouns like “my” in descriptions

Build It with MightyAI

MightyAI helps Shopify brands build high-performing ChatGPT Stores — integrating catalogs, powering conversations, existing vendors & AI on the Shopify store and connecting checkout flows seamlessly.

So while you’re laser-focused on this year’s Black Friday, start planning for next year’s biggest opportunity: In 2026, ChatGPT Store will be DTC’s most profitable new growth channel.

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