Modelcade: A Fun Model and Reasoning Capability Selector for ChatGPT

Modelcade is a Chrome browser extension. Addressing the complexity of ChatGPT's model selection experience, it restructures the model selection process via a magnetic interaction interface, supporting switches between models like Sol, Terra, Luna, and different reasoning intensities, making operations intuitive and fun. This extension is developed and maintained by x1f4r, released on GitHub on July 12, 2026, with a tech stack of JavaScript and Chrome Extension Manifest V3.

OpenAI adjusted ChatGPT's model naming system between 2025-2026 (from GPT-4o etc. to Sol/Terra/Luna), and expanded reasoning intensity into a continuous spectrum, increasing users' cognitive burden. Modelcade solves three key pain points:

1. Dispersed options: Native interface's model selection and reasoning intensity settings are distributed across different menu levels
2. Lack of intuitive comparison: Users find it hard to quickly identify differences between models and capability levels
3. Insufficient interaction feedback: The native selector has plain visual feedback The design goal is to simplify operations and enhance experience enjoyment.

Dual Layout Modes

• Compact Mode: Enabled by default; Chat interface displays capability levels on a horizontal track, Work interface uses a wheel to select models + vertical track to show reasoning intensity
• Full Mode: Retains the native path and removes invalid options

Magnetic Interaction

Selection controls automatically snap to valid options to prevent misoperations; supports direction key navigation, Enter confirmation, and Escape to close

Work Interface Details

• Models: Sol (amber-orange-gold gradient), Terra (ocean blue/vegetation green/cloud white), Luna (dark gray to light gray)
• Reasoning intensity: 5 levels (Low/Med/High/X-High/Max); Ultra mode is an independent toggle switch (mechanical sound effects + animation)
• Fast mode: Click the selected dot to switch between Standard/Fast

Chat Interface Details

Continuous capability spectrum (Instant→Med→High→X-High→Pro); the diagonal transition between 5.5 and Sol reflects the uniqueness of Instant; the selected part is filled with color.

• DOM Bridging: Manipulates DOM via content scripts to trigger native controls, reducing dependency on React architecture
• Visual Snapshot: Freezes the snapshot of the trigger button and delegates native operations
• Real-time Capability Discovery: Detects available options each time the selector is opened; falls back to native if fewer than two options are available
• Local State Management: Stores obfuscated settings (enabled status, layout preferences, etc.) with no sensitive information
• Shortcuts: macOS Control-Shift-M to quickly toggle the extension

Privacy Measures

• Runs only on the chatgpt.com domain
• Does not use OpenAI API keys or initiate network requests
• Does not read cookies or conversation content
• Stored data is obfuscated with no account identification information

Installation Steps

1. Open chrome://extensions and enable Developer Mode
2. Load the unpacked extension folder
3. Refresh the ChatGPT page to use

Design Details

• Liquid deformation effect: Stretching/sticky animation when the selection dot moves
• Precise geometric alignment: Gradient track round caps match the outer diameter of the dots
• Color sampling: Active labels and halos use the color of the selected position
• Animation choreography: Panel entry occurs only once; Ultra effect is not triggered repeatedly

Limitations

• Depends on the native interface structure; updates are required if ChatGPT is restructured
• Only supports the web version, not mobile/API
• Limited to Chrome browser

Future Directions

• Launch on Chrome Web Store
• Add custom themes
• Support preference export/import
• Add usage statistics function

Modelcade combines functionality and aesthetics, optimizing the high-frequency interaction of ChatGPT model selection. Magnetic interaction, color system, and smooth animations together enhance the experience. For heavy users who frequently switch models and reasoning intensities, Modelcade is worth trying.