what this repo knows — every node a real file, every edge a declaration in its frontmatter
37 files in the brain repo
schemaVersion: 1 id: nextjs-app-shell-convention type: convention domain: routing-app-shell title: Next.js App Router shell — a single client-rendered page under a thin RSC layout summary: The whole app is one route; layout.tsx is the only server component (fonts + metadata), and everything from page.tsx down is "use client" because the coagent hooks need the browser links: [provider-nesting-contract, copilotkit-runtime-route-convention, design-system-convention] cites: - src/app/layout.tsx:22 :: RootLayout - src/app/layout.tsx:6 :: localFont - src/app/page.tsx:1 :: "use client" - src/app/Main.tsx:8 :: Main - src/app/globals.css:15 :: @layer base description: "The whole app is one route; layout.tsx is the only server component (fonts + metadata), and everything from page.tsx down is 'use client' because the coagent hooks need the browser" tags: [routing-app-shell] timestamp: 2026-07-26T22:44:42.840Z
This is a single-route Next.js 15 App Router app — there are no nested route segments,
no [params], no additional page.tsx files. Orientation:
layout.tsx is the only real Server Component. It sets metadata (layout.tsx:17-20
— now the real product title, no longer the create-next-app scaffold), loads the two
local Geist fonts via next/font/local (layout.tsx:6-15), imports global CSS +
@copilotkit/react-ui/styles.css, and renders {children} inside <body>
(layout.tsx:22-35). Keep it server-side; don't add "use client" here.page.tsx opens the client boundary with "use client" at the top (page.tsx:1).
Everything below it — Main, ResearchCanvas, the dialogs, the model selector — is
client-rendered. This is deliberate and unavoidable: CopilotKit's useCoAgent/
useCopilotAction hooks and the model-selector context need browser state (URL params,
live streaming). Do not try to make these RSC. Corollary: most files under
src/components/ carry no "use client" directive yet are still client components —
the boundary was opened here, once. See
the design-system convention.page.tsx also owns provider composition — see
the provider nesting contract. Main.tsx is
the layout frame (header + split pane: ResearchCanvas left, CopilotChat right), seeds
the coagent initialState from the shared createInitialAgentState factory
(Main.tsx:10-13), and registers chat suggestions via useCopilotChatSuggestions
(Main.tsx:15-17).@/ → src/ (see components.json aliases: @/components, @/lib,
@/components/ui). Import via aliases, not relative paths.src/app/globals.css (:15 @layer base holds the design tokens). Body font is
overridden to Arial there despite the Geist font vars being wired in layout — a known
quirk, not a convention to copy.