--- title: "Learn - SEO, GEO & AEO issue guides - Serpwise" description: "Practical guides to the technical SEO, GEO, AEO, crawler, structured data, and performance issues that hold sites back." url: "https://serpwise.ai/learn/" source: "https://serpwise.ai/learn/" --- Learn # Diagnose blockers. Ship fixes. A practical library for the SEO, GEO, AEO, crawler access, structured data, and performance problems Serpwise audits and helps deploy at the edge. [Run free audit](/audit/) [Browse guides](#guides) Issue library ## Use Learn as the diagnostic layer before the execution layer. Each guide explains what breaks, how to detect it, and what usually needs to change. The goal is not more theory. The goal is knowing which fixes are worth shipping. 26 Guides 8 Critical issues 11 Issue areas Start here ## The issues that most often hide a site from crawlers and answer engines. These are the problems that turn good content into a weak search surface: blocked bots, client-side rendering gaps, bad status codes, and missing source signals. [01 \ Critical AI & Bot Visibility \ **AI bots are blocked from your site** \ A robots.txt or WAF rule can limit AI training, search inclusion, or on-demand retrieval. Audit each crawler separately before changing access. \ Read guide →](/learn/ai-bots-blocked/) [02 \ Critical AI & Bot Visibility \ **JavaScript rendering failures for crawlers** \ Find JavaScript rendering failures that hide content from crawlers, including hydration errors, delayed sections, client-side routing, and soft 404 patterns. \ Read guide →](/learn/javascript-rendering-failures/) [03 \ Critical Crawling & Indexing \ **Pages returning HTTP errors** \ 404, 410, 451, 500, 503 each tell a crawler something different. Pick the right code, find the patterns, fix the source - don't paper over with redirects. \ Read guide →](/learn/pages-with-http-errors/) ### AI & Bot Visibility 3 guides [Critical \ **AI bots are blocked from your site** \ A robots.txt or WAF rule can limit AI training, search inclusion, or on-demand retrieval. Audit each crawler separately before changing access. \ Read guide →](/learn/ai-bots-blocked/) [Critical \ **AI bots see different content than your visitors** \ Do not assume every crawler will render client-side JavaScript. Compare the raw response with the rendered page and keep primary content in the HTML. \ Read guide →](/learn/ai-bots-see-different-content/) [Critical \ **JavaScript rendering failures for crawlers** \ Find JavaScript rendering failures that hide content from crawlers, including hydration errors, delayed sections, client-side routing, and soft 404 patterns. \ Read guide →](/learn/javascript-rendering-failures/) ### Crawling & Indexing 5 guides [Critical \ **Broken internal links** \ Internal 404s interrupt navigation and send crawlers to dead URLs. Find the linking source, choose redirect or removal, and fix the template pattern. \ Read guide →](/learn/broken-internal-links/) [Critical \ **Pages returning HTTP errors** \ 404, 410, 451, 500, 503 each tell a crawler something different. Pick the right code, find the patterns, fix the source - don't paper over with redirects. \ Read guide →](/learn/pages-with-http-errors/) [Critical \ **robots.txt mistakes beyond AI bots** \ Blocking JS/CSS kills rendering. \`Disallow: /\` deindexes the site. robots.txt is not regex, not enforcement, and not the right tool to hide secrets. \ Read guide →](/learn/robots-txt-mistakes/) [Warning \ **Slow page response times** \ Slow TTFB delays every later rendering milestone and can reduce crawl efficiency at scale. Separate network time from origin work before choosing a fix. \ Read guide →](/learn/slow-page-response-times/) [Warning \ **XML sitemap hygiene issues** \ Stale URLs, oversized files, lying lastmod dates, and sitemaps listing non-indexable URLs all degrade the signal. How to keep a sitemap that Google trusts. \ Read guide →](/learn/sitemap-xml-issues/) ### Page Metadata 5 guides [Warning \ **Duplicate title tags** \ Identical titles across pages are almost always a template bug. Find the source, template a unique title per page, don't paper over with noindex. \ Read guide →](/learn/duplicate-title-tags/) [Warning \ **Missing title tag** \ Without a title element, search engines may generate a title from page text. Learn how to detect missing titles and write a clear, descriptive replacement. \ Read guide →](/learn/missing-title-tag/) [Warning \ **Title tag too long** \ Search results may shorten long page titles or generate a different title link. Keep titles concise, descriptive, distinctive, and useful on any device. \ Read guide →](/learn/title-tag-too-long/) [Info \ **Missing H1 heading** \ The H1 heading names a page's primary topic for readers, assistive technology, and search engines. Learn how to audit and fix missing or unclear headings. \ Read guide →](/learn/missing-h1-heading/) [Info \ **Missing meta description** \ Google may use a meta description when it explains a page better than visible content. Write a concise, specific summary for people, not an algorithm. \ Read guide →](/learn/missing-meta-description/) ### Structured Data 2 guides [Warning \ **Invalid structured data** \ Invalid JSON-LD costs rich-result eligibility and can quietly trip quality signals. Read the validator, fix required properties, re-test. \ Read guide →](/learn/invalid-structured-data/) [Info \ **Missing structured data** \ Structured data gives search systems explicit facts about a page. Use supported schema types accurately and never treat markup as a ranking guarantee. \ Read guide →](/learn/missing-structured-data/) ### Performance & Core Web Vitals 3 guides [Warning \ **Cumulative Layout Shift (CLS)** \ Learn how CLS measures unexpected layout movement, how to diagnose unstable elements, and how reserved space, image dimensions, and font metrics reduce shifts. \ Read guide →](/learn/cumulative-layout-shift/) [Warning \ **Interaction to Next Paint (INP)** \ INP replaced FID as a Core Web Vital in March 2024. It measures the worst observed interaction delay, not the first. How to find long tasks and fix them. \ Read guide →](/learn/interaction-to-next-paint/) [Warning \ **Largest Contentful Paint (LCP)** \ Learn how to identify the Largest Contentful Paint element, measure field performance, and fix the server, resource, rendering, and discovery delays behind slow LCP. \ Read guide →](/learn/largest-contentful-paint/) ### Canonicalization 2 guides [Warning \ **Cross-domain canonical tag** \ A cross-domain canonical nominates another URL as the preferred version. It can be intentional for syndication, but often reveals a migration or template bug. \ Read guide →](/learn/cross-domain-canonical-tag/) [Warning \ **Missing canonical tag** \ Without an explicit canonical, Google picks one - often the URL with tracking params, a paginated variant, or a duplicate. Add a self-referential canonical. \ Read guide →](/learn/missing-canonical-tag/) ### International & Mobile 2 guides [Critical \ **Mobile and desktop content parity** \ Audit mobile and desktop content parity so Google can find the same primary content, metadata, structured data, images, and internal links on both versions. \ Read guide →](/learn/mobile-desktop-content-parity/) [Warning \ **Hreflang mistakes that break international targeting** \ Missing return tags, mismatched language codes, region-without-language, and other hreflang implementation bugs that quietly break geo-targeted indexing. \ Read guide →](/learn/hreflang-mistakes/) ### Site Architecture 1 guides [Info \ **Orphan pages with no internal links** \ Pages with no internal links are hard to discover and receive no internal authority. They quietly accumulate over years and waste content investment. \ Read guide →](/learn/orphan-pages-no-inlinks/) ### Security & HTTPS 1 guides [Critical \ **Mixed content on HTTPS pages** \ Insecure HTTP resources on HTTPS pages get blocked by browsers, break rendering, and signal a security misconfiguration to crawlers. How to find and fix them. \ Read guide →](/learn/mixed-content-on-https/) ### Images & Media 1 guides [Info \ **Image SEO: formats, sizing, lazy-loading, alt text** \ Modern image practice for SEO: WebP/AVIF, responsive srcset, native lazy-loading, alt text that earns image search traffic, and the byte budgets that matter. \ Read guide →](/learn/image-seo/) ### DNS & Hosting 1 guides [Info \ **Shopify shows Invalid DNS behind an edge proxy** \ Understand why Shopify can show an Invalid DNS warning when a storefront runs through an edge proxy, how to verify the route, and which records not to change. \ Read guide →](/learn/shopify-invalid-dns-warning/) From diagnosis to deployment ## Find the issue. Ship the fix. Use Learn to understand the problem, then run Serpwise against your own site to see what can be approved and deployed. [Run free audit](/audit/) [Book a demo](/demo/)