Technical Seo

Technical SEO

Audit fundamental technical SEO factors that affect crawlability and indexability.

1. Canonical URL

| Check | Status | |---|---| | ` missing | ⚠️ WARN "Add canonical to prevent duplicate content" | | Canonical present but empty href` | ❌ FAIL | | Canonical points to a different domain | ⚠️ WARN "Cross-domain canonical — verify this is intentional" | | Canonical is relative (not absolute URL) | ⚠️ WARN "Use absolute URLs for canonical tags" | | Canonical present and valid | ✅ PASS | | Multiple canonical tags | ❌ FAIL "Only one canonical allowed per page" | | Canonical is self-referencing | ✅ PASS (best practice) |

2. Robots meta

| Check | Status | |---|---| | ` | ⚠️ WARN "Page will not appear in search results" | | | ⚠️ WARN "Links on this page will not be followed" | | | ⚠️ WARN "Page excluded from search entirely" | | or absent | ✅ PASS "Page is indexable" | | ` present | ✅ PASS — report its content |

3. Robots.txt references

Check if the page references or is affected by robots.txt:

• Look for `` directives
• If analysing a full site, check robots.txt at site root for:
• Disallow rules that block the current page
• Sitemap directive pointing to sitemap location
• Crawl-delay directives (may slow indexing)

4. Sitemap references

| Check | Status | |---|---| | `` present | ✅ PASS | | No sitemap reference found | ⚠️ WARN "Consider adding sitemap reference" |

If sitemap URL is available, verify:

• Valid XML format
• Contains the current page URL
• No URLs returning 4xx/5xx status codes

5. URL structure

Analyse the page URL (from ` or `):

| Check | Status | |---|---| | URL contains uppercase letters | ⚠️ WARN "Use lowercase-only URLs" | | URL contains underscores | ⚠️ WARN "Use hyphens instead of underscores" | | URL contains special characters or spaces (encoded %20) | ⚠️ WARN "Simplify URL structure" | | URL exceeds 100 characters | ⚠️ WARN "Keep URLs concise" | | URL has double slashes (//path) | ❌ FAIL "Fix double slashes" | | URL has trailing slash inconsistency | ⚠️ WARN "Be consistent with trailing slashes" | | Clean, descriptive, lowercase with hyphens | ✅ PASS |

6. HTTP status hints

| Check | Status | |---|---| | ` present | ⚠️ WARN "Use 301 redirects instead of meta refresh" | | Page contains window.location` redirect in inline script | ⚠️ WARN "JS redirects are not SEO-friendly" |

7. Indexability checklist

| Check | Status | |---|---| | Has ` tag | Required for indexing | | Has | Required for SERP snippets | | Has unique content (not empty ) | Required | | Not blocked by noindex` | Required | | Has canonical URL | Recommended | | Is HTTPS (check canonical/og:url) | ⚠️ WARN if HTTP |

8. Pagination

| Check | Status | |---|---| | ` / ` present | ✅ PASS "Pagination properly marked" | | Paginated content without prev/next | ⚠️ WARN "Add for multi-page content" |

9. Duplicate content signals

| Check | Status | |---|---| | Same `` as canonical page but different URL | ⚠️ WARN | | No canonical + URL has query parameters | ⚠️ WARN "URL parameters may create duplicate pages" | | Multiple pages with identical meta description | ⚠️ WARN |

Edge cases

• Next.js app router generates canonical tags automatically via the metadata export — audit the rendered HTML output
• robots.txt may not be accessible if auditing a single HTML file — note this limitation and skip robots.txt checks
• Pages behind authentication (login walls) may intentionally use noindex — flag as ⚠️ WARN but note context
• Single-page applications with client-side routing may have a single canonical URL for all "pages" — flag as ⚠️ WARN
• Staging/preview environments often have noindex — distinguish between intentional and accidental noindex when possible
• Pages with rel="prev" / rel="next" are deprecated by Google (since 2019) but still supported by Bing — note as informational, not FAIL

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: thisisAhsanIqbal
• Source: thisisAhsanIqbal/nextjs-seo-audit
• License: MIT
• Homepage: https://nextjs-seo-skill.vercel.app/

Install and usage instructions live in the source repository linked above.