Missing SEO and social sharing basics
Even a great product is hard to find without the basics of search engine and social media metadata. A missing sitemap keeps you out of Google. A missing OG image makes every shared link look broken.
#What goes wrong
AI scaffolds rarely add a sitemap, robots.txt, Open Graph image, theme color, web app manifest, or Apple touch icon by default. The app works, but every share looks like a generic placeholder, and search engines have to guess what your site is about.
#Why it matters
Without an OG image, your link previews on Twitter, Slack, Discord, and LinkedIn look unprofessional. Without a favicon, your tab is a generic globe. Without a sitemap, indexing is slower and less reliable. None of these break the app, but together they cost real signup conversions.
#How Heimdall checks for this
Heimdall verifies the presence of robots.txt, a sitemap (file or dynamic route), favicons across desktop and Apple, a web app manifest, a theme color, and either an OG image file or an opengraph-image route. Each missing piece is reported with a fix prompt that knows about Next.js App Router conventions.
#How to fix it
In Next.js App Router, add app/robots.ts, app/sitemap.ts, app/icon.png, app/apple-icon.png, app/manifest.ts, and app/opengraph-image.tsx. Set a themeColor in your root layout. Each file is just a few lines and unlocks the full set of metadata signals.
Frequently asked questions
Do I need both icon.png and apple-icon.png?
Can I skip the OG image?
What is the right theme color?
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