Gemini Default Model Setter

Automatically selects a specific model and its Thinking Level for Gemini upon page load, URL change, or tab return. The target patterns and script state can be easily configured via the extension menu.

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Author

p65536

Daily installs

Total installs

Ratings

1 0 0

Version

1.1.0

Created

2026-05-14

Updated

2026-05-21

Size

39 KB

License

MIT

Applies to

google.com

Overview

Gemini Default Model Setter (GDMS) is a helper script designed for AI power users. It automatically forces Google Gemini to use your preferred specific model (e.g., "Flash" or "Pro") upon page load, URL change, or tab return.

Stop manually selecting your preferred model every time you start a new conversation. This script ensures you always start with your target model, while still preserving your freedom to manually switch to a different model (like "Flash" for quicker tasks) during the chat.

Key Features

Automatic Selection: Instantly selects your specified target model and its Thinking Level when starting a new chat or opening an existing history thread.
Regex Targeting: Easily configure both your target model and its Thinking Level using case-insensitive Regular Expressions (e.g., Pro for model, Extended or Deep Think for thinking level) via an intuitive settings modal.
Multilingual Support: Since the model names are captured via user-defined Regular Expressions, the script is inherently compatible with all Gemini interface languages without any extra setup.
Preserves Manual Control: Sets the initial state but allows you to seamlessly switch models or thinking levels manually if you need a different setup mid-task.
Auto-Check on Re-focus: An optional fail-safe feature that re-verifies and sets your target configurations when returning to the Gemini tab (useful for background loads or idle sessions).

Screenshots & Integration

Settings Modal

Perfect Match: Works seamlessly with AI UX Customizer to enhance the overall visual interface and navigation of your AI chats.

Getting Started & Usage Guide

Initial Setup: Click your userscript manager extension icon (e.g., Tampermonkey) while on the Gemini page. Click "⚙️ Set Target Model Name" or "⚙️ Set Thinking Model Name" to open the settings modal. Input your desired model pattern (e.g., Pro) and optionally configure the target thinking level (e.g., Extended). Leave the thinking level blank if you do not want the script to modify or interfere with the model's current thinking level setting.
Past Chat History: When you click a past chat thread from the sidebar, the script will automatically switch it to your target model, allowing you to seamlessly continue past brainstorming with your highest-tier model.
About "Auto-Check on Re-focus":
- Default is OFF.
- When turned ON, the script checks the model and thinking level every time you switch back to the Gemini tab. This is great for idle tabs, but note: if you manually changed the model or customized the thinking level and then switched browser tabs, returning to Gemini will automatically reset them back to your target configurations. Keep this OFF if you frequently use manual switching alongside heavy tab-switching.

Tested Environment

This script is primarily developed and tested on Firefox with Tampermonkey.
It is also confirmed to work on Chromium-based browsers, but testing on these platforms is less extensive.

More info

Full Guide & Details on GitHub:

AI UX Customizer

This script is open-source and licensed under the MIT License.