The catalogue

All 46 checks, and what each can do.

Plenty of tools claim they fix everything. That’s how sites break. Every check declares up front whether it can write the fix, or whether it can only tell you what’s wrong.

46checks in total
30write a real fix
43need no external key
9categories

Filter the list

Search by name, or narrow by category and what the check is able to do.

#CheckCategoryCapability
1Permalink StructureTechnicalFixable
2Robots.txtTechnicalFixable
3XML SitemapTechnicalAdvisory
4Canonical TagsTechnicalFixable
5Not Indexed Pages Search ConsoleTechnicalFixable
6Page TitlesContentFixable
7Meta DescriptionsContentFixable
8Thin ContentContentAdvisory
9Low CTR Pages Search ConsoleContentAdvisory
10Declining Keywords Search ConsoleContentAdvisory
11High Bounce Rate Pages AnalyticsContentAdvisory
12Low Engagement Pages AnalyticsContentAdvisory
13Broken Internal LinksLinksFixable
14Internal Pages That RedirectLinksAdvisory
15External Link AttributesLinksFixable
16Broken Backlinks Data keyLinksAdvisory
17Domain Authority Data keyLinksAdvisory
18Toxic Backlinks Data keyLinksAdvisory
19Image Alt TextImagesFixable
20Oversized ImagesImagesFixable
21Next-Gen Image FormatImagesAdvisory
22WordPress Version ExposedSecurityFixable
23Security HeadersSecurityFixable
24Mixed ContentSecurityFixable
25404 Attack-Pattern FirewallSecurityFixable
26Product Schema WooStructured dataFixable
27Product Review Schema WooStructured dataFixable
28Product Schema Missing Fields WooStructured dataFixable
29Organization SchemaStructured dataFixable
30Article SchemaStructured dataFixable
31LocalBusiness SchemaStructured dataSnippet
32Breadcrumb SchemaStructured dataFixable
33Caching HeadersPerformanceAdvisory
34Core Web Vitals PageSpeedPerformanceAdvisory
35Hreflang TagsInternationalFixable
36FAQ Schema OpportunityAI readinessFixable
37AI Direct-Answer FormattingAI readinessFixable
38Author Authority (E-E-A-T)AI readinessFixable
39Speakable SchemaAI readinessDormant
40HowTo SchemaAI readinessDormant
41AI Content StructureAI readinessFixable
42llms.txt for AI CrawlersAI readinessFixable
43Cited External SourcesAI readinessFixable
44Supporting StatisticsAI readinessFixable
45Expert QuotationAI readinessFixable
46Content FreshnessAI readinessFixable
What the labels mean

Three honest categories

The distinction matters. A tool that pretends everything is auto-fixable is a tool that will eventually write something it shouldn’t.

Fixable — 30 checks

The plugin writes the change itself. You still preview it and approve it first, and every write stores a rollback record before it runs. Some are deterministic, some are AI-assisted.

Advisory — 14 checks

The problem is real but the fix needs judgement, server access or a human decision. You get the finding, the affected pages and clear guidance — not a button that guesses.

Dormant — 2 checks

Speakable and HowTo schema shipped, then Google retired the rich results they fed. The code stays for the day that changes, but it doesn’t run and doesn’t inflate the count.

Keys and coverage

Most of this works with nothing connected

43 of the 46 checks run on a bare install. The rest read data only Google or a backlink provider can give you, and they’re marked as such in the table above.

  • No key at all — 43 checks, including every deterministic fix
  • Search Console & Analytics — adds indexation, click-through, decline and engagement checks
  • A backlink data key — adds the three link-authority checks
  • An Anthropic key — unlocks the AI-written fixes across content and AI readiness
seo-merlin — issues by category
Screenshot slot 12Issues list, grouped by category
1600 × 1040 recommended

Run all 46 on your own site. Free.

Scanning and reporting are never limited on the free tier. You’ll see exactly which of these fire on your pages before you spend anything.

WordPress 6.5+ · PHP 8.1+ · Works with your existing SEO plugin