> ## Documentation Index > Fetch the complete documentation index at: https://subtext.fullstory.com/docs/llms.txt > Use this file to discover all available pages before exploring further. # Install Subtext in a Next.js App Router Application > Add the Subtext capture snippet to your Next.js App Router project by inserting it into app/layout.tsx using the Script component. The fastest way to add Subtext to a Next.js App Router project is to drop the capture snippet into your root layout file. Because `app/layout.tsx` wraps every route in your application, the snippet loads once and records sessions across your entire site. The ` {children} ); } ``` The `id` prop on `