Grammar Wise Custom Web Search is a Firefox add-on designed to improve users' writing skills and streamline their web searches. This subscription-based tool offers a variety of writing assistance features, including a dictionary, thesaurus, spell-checker, and grammar checker. It enables users to quickly access word definitions, synonyms, and antonyms, while also helping to identify and correct common spelling and grammatical errors. The tool is integrated into the browser, allowing users to enhance their written communication effortlessly.

In addition to its writing assistance capabilities, Grammar Wise Custom Web Search allows users to perform custom web searches directly from their browser. With Yahoo! as the default search provider, users can easily find information across various categories like news, weather, images, and videos. The intuitive toolbar icon provides quick access to all features, making it a valuable resource for anyone looking to improve their writing and search efficiency.