The Auto Definition Link plugin for Obsidian automates the process of creating links to blocks within your vault. It offers two main modes: Suggestion Mode, where users can select link suggestions, and Auto Link Mode, which automatically converts block IDs into links after pressing a valid key. The plugin makes it easy to maintain consistent linking without worrying about capitalization or plurality. It only scans markdown files in the same folder as the current document, ensuring focused linking within specific areas. Both modes can be toggled on or off in the settings, allowing users to customize their experience.