> For the complete documentation index, see [llms.txt](https://docs.preva1l.info/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.preva1l.info/fadah/setup/category-filtering-and-blacklists.md). # Category Filtering & Blacklists Category filters and blacklists use the same system internally.\ Strings check for booleans (true or false) and are parsed using javascript.\ You can use any javascript methods that are for comparison and you can use the following placeholders: `%lore%` `%name%` `%amount%` `%material%` Some examples would be:\ `%lore%.includes("Mythical Item")` would match true if the items lore has "Mythical Item" anywhere in it.\ You can also use logical operators (such as && and ||) for example: `%name% == "Custom Item" && %amount% >= 3` would match if the name is "Custom Item" and there is 3 items in the stack. ### Additional Hooks Some hooks are also added for more filtering options.\ Currently there is; EcoItems. #### EcoItems `%ecoitems_id%` --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.preva1l.info/fadah/setup/category-filtering-and-blacklists.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.