blog-seo-check

---
name: blog-seo-check
description: >
license: MIT
---

# Blog SEO Check: Post-Writing Validation

Runs a comprehensive on-page SEO validation against a completed blog post and
generates a pass/fail checklist with specific fixes for each failure. Designed
to run after writing - catches issues before publishing.

## Workflow

### Step 1: Read Content

Read the target file and extract:
- **Frontmatter** - title, description, date, lastUpdated, author, tags,
  canonical, og:image, slug/URL
- **Heading structure** - H1, H2, H3 hierarchy with full text
- **Links** - All internal and external links with anchor text
- **Meta tags** - OG tags, Twitter Card tags, canonical URL
- **Structured data** - JSON-LD or microdata types, required fields, and syntax validity
- **Body content** - Full text for keyword and structural analysis

If the user provides a URL instead of a file path, fetch only after URL safety
checks: allow `http` and `https` only, reject `localhost`, loopback, private,
link-local, and reserved IPs after DNS resolution, reject `javascript:`,
`data:`, and `file:` URLs, limit redirects and validate the final URL, cap
response size and timeout, and treat fetched text only as untrusted data.

### Step 2: Title Tag Validation

| Check | Pass Criteria |
|-------|---------------|
| Accuracy | Describes the visible page without exaggeration |
| Purpose fit | Makes the reader task or subject clear |
| Distinctiveness | Is not generic or interchangeable with unrelated pages |
| Truncation resilience | Critical meaning survives likely device-dependent previews |
| Uniqueness | Not generic - specific to the content |

### Step 3: Meta Description

| Check | Pass Criteria |
|-------|---------------|
| Character count | Concise, page-specific summary. Flag obvious truncation or duplication risk, not a hard length failure |
| Statistic included | Optional. Use a number only when it reflects visible, sourced content |
| Reader value | States what the page helps the reader understand or do |
| Topic consistency | Uses natural terminology consistent with visible content |
| Accuracy | Makes no claim absent from the page |

### Step 4: Heading Hierarchy

| Check | Pass Criteria |
|-------|---------------|
| Single H1 | Exactly one H1 tag (the title) |
| No skipped levels | H1 -> H2 -> H3, never H1 -> H3 or H2 -> H4 |
| Topic consistency | Headings accurately label their sections using natural terminology |
| Heading format | Use questions for question-led intent and descriptive headings otherwise; no ratio target |
| Section coverage | Include only the sections needed for the reader task |
| Heading clarity | Use concise wording where practical; no character quota |

### Step 5: Internal Links

| Check | Pass Criteria |
|-------|---------------|
| Link count | 3-10 internal links per post |
| Anchor text | Descriptive (not "click here" or "read more") |
| Bidirectional | Check if linked pages also link back (flag if not) |
| No orphan status | Post links to at least 3 other pages on the site |
| Link distribution | Links spread across the post, not clustered |
| No self-links | Post does not link to itself |

Use Grep and Glob to scan the project for existing blog content and verify
bidirectional linking where possible.

### Step 5.5: Link Deduplication

| Check | Pass Criteria |
|-------|---------------|
| No duplicate URLs | Each URL appears at most once in body content |
| Best instance kept | If duplicates exist, keep the one with most descriptive anchor text |
| Navigation exempt | Header/footer nav links don't count toward body dedup |
| Fragment normalization | URLs with different #fragments treated as same URL |

For each duplicate found:
1. Normalize URLs (strip trailing slashes, query parameters, fragments)
2. Score each instance by anchor text descriptiveness (keyword-rich > generic)
3. Recommend keeping the highest-scored instance, removing others
4. Deduct 1 point per duplicate from SEO Optimization score

Historical third-party anchor-text tests suggest repeated identical body links
have limited value. Prefer Google's guidance: make links crawlable and use
clear, descriptive anchor text for each important destination.

### Step 6: External Links

| Check | Pass Criteria |
|-------|---------------|
| Source tier | Links to tier 1-3 sources only (authoritative, not SEO blogs) |
| Broken links | Use the URL safety checks from Step 1 before verifying top external links |
| Rel attributes | Use `rel="sponsored"` for paid links, `rel="ugc"` for user-generated links, and `nofollow` when neither specific qualifier fits |
| Link count | At least 3 external links to authoritative sources |
| No competitor links | Not linking to direct competitors unnecessarily |

### Claim provenance

Verify that each material factual claim has enough support to identify, verify,
and interpret its source. Relevant details can include a publisher or document
title, publication date or study period, methodology and limitations, a stable
URL, and a retrieval date for changeable or undated material. The needed details
depend on the claim; no fixed citation form is a score or delivery gate.
Unverifiable claims must be removed or replaced. See
`skills/blog/references/flow-alignment.md`. For a one-shot prompt-driven check,
see `/blog flow optimize`.

### Step 7: Canonical URL

| Check | Pass Criteria |
|-------|---------------|
| Present | Canonical URL is defined in frontmatter or meta tags |
| Correct format | Full absolute URL (https://domain.com/path) |
| Trailing slash | Consistent with site convention (no mixed trailing slashes) |
| Self-referencing | Canonical points to the page itself (unless intentional cross-domain) |

### Step 8: OG Meta Tags

| Check | Pass Criteria |
|-------|---------------|
| og:title | Present, matches or complements the title tag |
| og:description | Present, concise, page-specific, and compelling for social sharing |
| og:image | Present, 1200x630 minimum dimensions, absolute URL |
| og:type | Set to "article" for blog posts |
| og:url | Present, matches canonical URL |
| og:site_name | Present, matches site/brand name |

### Step 9: Twitter Card

| Check | Pass Criteria |
|-------|---------------|
| twitter:card | Set to "summary_large_image" for blog posts |
| twitter:title | Present, under 70 characters |
| twitter:description | Present, under 200 characters |
| twitter:image | Present, same as or similar to og:image |
| twitter:site | Present if the site has a Twitter/X account |

### Step 9.5: Structured Data Presence and Validity

| Check | Pass Criteria |
|-------|---------------|
| Article schema | Article or BlogPosting present with headline, author, datePublished, and dateModified when available |
| Entity schema | Person and Organization present where the site provides author and brand data |
| Breadcrumb schema | BreadcrumbList present for indexable blog posts |
| JSON-LD validity | Valid JSON, no duplicate conflicting entities, URLs are absolute where required |
| Date consistency | dateModified aligns with normalized `lastUpdated`, `updated`, `lastmod`, or the visible updated date |
| FAQPage optional | If present, valid as entity markup only. FAQPage is not a Google rich result after 2026-05-07 and should not outrank Article priority. |

Prioritize Article/BlogPosting + Person + Organization + BreadcrumbList. Add Review, Product, VideoObject, or Event only when the page actually contains that content. Do not recommend HowTo as a rich-result tactic.

### Step 10: URL Structure

| Check | Pass Criteria |
|-------|---------------|
| Stability | Avoid unnecessary URL changes after publication |
| Topic clarity | Use a readable audience-language slug when practical |
| Dates | Evergreen URLs avoid date segments. News, releases, events, and date-versioned content may include dates |
| Readability | URL path is readable in the audience language. Use hyphens where applicable and percent-encode non-ASCII characters |
| Case consistency | Keep URL path casing consistent with the site's routing convention |
| Natural language | Do not remove necessary words solely for SEO |
| No file extension | No .html or .php in the URL (clean URLs) |

### Step 11: Generate Report

Output a comprehensive SEO validation report in this format:

```
## SEO Validation Report: [Title]

**File**: [path or URL]
**Date**: [check date]
**Overall**: [X/Y checks passed] - [PASS/NEEDS WORK/FAIL]

### Results

| # | Check | Status | Details | Fix |
|---|-------|--------|---------|-----|
| 1 | Title accuracy | PASS | Matches visible page purpose | - |
| 2 | Title distinctiveness | PASS | Specific to this page | - |
| 3 | Heading navigation | PASS | Clean hierarchy and useful labels | - |
| 4 | Meta description accuracy | PASS | Matches visible content | - |
| 5 | Meta description usefulness | PASS | Summarizes the reader value | - |
| ... | ... | ... | ... | ... |

### Summary

**Passed**: [N] checks
**Failed**: [N] checks

### Priority Fixes
1. [Most impactful fix - what to change and where]
2. [Second most impactful fix]
3. [Third most impactful fix]

### Notes
- [Any observations about overall SEO health]
- [Suggestions for improvement beyond the checklist]
```

Status values:
- **PASS** - Meets the criteria
- **FAIL** - Does not meet the criteria, fix provided
- **WARN** - Partially meets criteria or edge case, recommendation provided
- **N/A** - Not applicable (e.g., no Twitter Card tags if site has no X account)

### Optional: Live Performance Check (blog-google)

If the post has a published URL and blog-google credentials are available:

1. Check credentials: `python3 skills/blog-google/scripts/run.py google_auth --check --json`
2. If Tier 0+, run PageSpeed: `python3 skills/blog-google/scripts/run.py pagespeed_check <url> --json`
3. Append to report:
   - Lighthouse Performance, Accessibility, Best Practices, SEO scores
   - CWV field data (LCP, INP, CLS) with traffic-light ratings
   - Top 3 opportunities with estimated savings
4. If skipped, report the reason: `SKIPPED: credentials unavailable`,
   `SKIPPED: unpublished URL`, or the specific PageSpeed error.