JLJason LeeBuild library The video companion

Fable 5.1 vs. Astra

Four builds. The same starting ideas.
See the results, then try the prompts yourself.

Download the prompt pack
By Jason LeeSeptember 2026

Each build pairs both models’ results with a copyable prompt.
Time estimates a one-shot build. API cost is in USD for recorded work, including revisions.

Kyoto city explorer

A miniature city you can explore, with landmarks, guided flights, and a saved itinerary.

Fable 5.1

Kyoto Scout
Build time (est.)
~50 min
API cost
$146.80*

*Saved record uses Opus proxy rates, not confirmed Fable pricing. Includes all three build phases.

Astra

Kyoto Atlas
Build time (est.)
~40 min
API cost
$20.22

External tools & services
Final versions: Three.js loaded from a CDN; Astra also loads an icon font and a reference photo. No API keys needed. The original Cesium brief below would need Google Maps and Cesium credentials.

The prompt

Act as an expert 3D web developer and UX specialist. I want to build a clean, single-file HTML/JS web application using **CesiumJS** integrated with **Google Photorealistic 3D Tiles** to render a high-fidelity 3D digital twin of Kyoto, Japan.

**Target User & Intent:** The primary user is a traveler planning a trip to Kyoto who wants to explore the city virtually before arriving. Their goal is to understand the layout, neighborhood placements, walking distances, and spatial relationships between key spots so they can confidently plan their itinerary.

**Requirements:**

1. Use Google Photorealistic 3D Tiles for 1:1 real-world visual accuracy of Kyoto's buildings, terrain, and landmarks.
2. Include an automated **"Flight Mode"** button that smoothly flies the camera through iconic locations to give users an instant spatial overview of the city.
3. Based on the target user's goals, design and implement the features, UI controls, filters, and interactivity (e.g., interactive POIs, neighborhood navigation, modals) that you determine would be most valuable for a tourist virtually scouting Kyoto.

Include smooth camera controls, modern UI styling, atmospheric lighting, clear setup instructions, and placeholders for `Cesium.Ion.defaultAccessToken` and the Google Maps API key. Build in localhost using an available port.

FINAL SCOPE UPDATE (overrides the Cesium / Google Tiles requirement above):
Use Three.js to recreate the actual structures as a detailed 3D miniature, rather than an embedded map. Focus on a small, navigable part of Kyoto dense with 10–20 popular attractions. Model the windows, colors, roofs, and architectural details, using an attached city-miniature reference video. Keep the traveler features and guided flights. The scope should be achievable in one build, not days of work.

Original starting brief plus a consolidated final-scope update. Local port normalized; attach a city-miniature reference video. Both final builds use Three.js.

Ski clothing store

An original ski brand, a cinematic hero, model photography, and a working demo checkout.

Fable 5.1

OSTRA
Build time (est.)
~10 min
API cost
~$4.70

Cost is a rough session estimate (±30%).

Astra

RIFT Alpine
Build time (est.)
~23 min
API cost
$11.59

External tools & services
Higgsfield for image and video generation; Three.js for Fable’s 3D section. Astra uses Sites D1 for cart/orders, with optional Stripe for real payments. Both previews use demo checkout.

The prompt

Build a fully functional e-commerce website for a ski clothing brand similar to the north face, come up with your own brand name, style, typography, colors and branding. I want the hero section to contain a video of people doing skiing or snowboarding activities, with multiple different scenes combined together. I want the site to convey high-energy and premium feel. You can use Three.js for any 3D rendering for any section as needed. For the products, come up with the product line and also the photos or videos for the models of each product. Every product needs to have a human model. You can use Higgsfield MCP to generate any images or videos.

Whisper for Mac

A voice dictation launch page with original branding, generated films, and interactive scenery.

Fable 5.1

Whisper
Build time (est.)
~35 min
API cost
$48.50

Astra

Whisper
Build time (est.)
Not recorded
API cost
Not recorded

No saved time or API-cost report found in this project.

External tools & services
Higgsfield for original artwork and Seedance 2.5 video. Cool Dock and Wispr Flow are design/feature references. Astra uses Sites D1 for early-access signups; the dictation interactions are demonstrations.

The prompt

I want to design a landing page for my Mac app. It is a voice dictation app called Whisper. It is similar to Wispr Flow. I want you to take a look at the website Cool Dock, and I want you to use that same design, typography, and feel of that website, but adapt it for my Whisper app. Come up with the app icon and any other assets that you need to match my product. If there's any walkthrough video, I want you to come up with it as well. Any type of images and animations should be created using the Higgsfield MCP connected. You have access to all the image models and, particularly, use Seedance 2.5 for any video generation. Make the website launch-ready so the copy and the image/video assets should all be generated.

https://www.dock.cool/
https://wisprflow.ai/

FINAL DESIGN NOTES:
Watch an attached screen recording of Cool Dock closely. Create original Whisper branding rather than copying Wispr Flow. Use a simple flat vector app icon and an original dictation pill. Include animated scenery and a soft cursor-following foliage reveal on the rocks: plants should appear only around the cursor and disappear as it moves away, not reveal the whole rock.

Original brief plus consolidated design follow-ups; the private recording path is removed. Attach your own Cool Dock reference recording when recreating it.

Receipt Scan

Scan a receipt, review the details, organize expenses, and export reports. Plus a companion landing page.

Fable 5.1

Receipt Scan
Build time (est.)
~36 min
API cost
$86.86

Astra

Receipt Scan
Build time (est.)
~1 hr 35 min
API cost
$59.80

External tools & services
Supabase for authentication, database, storage, and server functions; Anthropic API for receipt extraction; Expo / EAS for mobile previews and builds; Higgsfield for branding. Supply your own credentials securely.

The prompt

https://apps.apple.com/au/app/receipt-scanner-easy-expense/id1528787066

I want you to build a iOS mobile app similar to the app in the URL above. Call it Receipt Scan. I want you to have the basic feature of scanning a receipt and categorizing everything from merchant amounts, tax, etc. match the features of the app to the receipt scanner app I also want you to use Supabase as the database. I want to use react native to build the app and use expo eas build for me to test the app. I will be using Open AI, api key for the AI functionality of scanning the receipt. Ask me when you get to that point. Populate the app with some dummy data but when I test the app, I should be able to scan a physical receipt and the information should be organized in the app where I can manage the app. I also want you to build the app screenshots to submit to the App Store design this so it matches the branding. I want you to come up with the color theme typography and app icon. I want the icon to be a flat vector style. Use your image generation tool to generate any images and after that I want you to build a simple landing page to promote the app. I will give you a freedom to design this learning page find the best practices in how a landing page for a software or a mobile app should look like what sections you need and impress me with what you build. I thought you finish. I should be able to just download the app from my on my iOS device to test it up. Ask me questions if unclear about anything. This is an end to end build, so make it as complete as possible.

FINAL SCOPE UPDATES (override earlier choices):
Use Notion-style branding and illustrations, with an original flat vector icon. Use Higgsfield for image generation. Use the Anthropic Claude API instead of OpenAI for receipt extraction, keeping its key on the server. Use Expo Go for initial iPhone testing and allow guest access without an app login. Keep the standalone EAS build as a later step. Ask for credentials securely when needed; never include real keys in the client.

Astra’s starting wording plus consolidated final-scope updates. Fable’s original brief already included Notion branding and Higgsfield; Astra received the branding direction later. Both switched to Claude and Expo Go.