Seo migration check

Skill lionkiii/claude-seo-skills/skills/seo-migration-check

Validate SEO preservation during site migrations. Checks redirect chains (301 vs 302, hop count), canonical consistency, title/meta preservation, HTTP status codes, content similarity, and schema preservation. Accepts single URL pair or CSV file of URL pairs. Use when user says "migration check", "site migration", "redirect audit", "URL mapping", "domain change", "relaunch", "site move".From its SKILL.md

Install

npx -y skills add lionkiii/claude-seo-skills --skill seo-migration-check

Assembled from the repository path, not quoted from the project. Check it against their README if it does not work.

One thing to look at

20 stars20 stars. Stars are a popularity signal and not a quality one, but at this level it is likely that nobody has read this closely except its author, and you would be relying on your own review.

SKILL.md

4.2 KB, 971 tokens by cl100k_base, as published. Nobody here has run it

Site Migration SEO Validator

Validates redirect chains, canonical tags, metadata, and content preservation during site migrations.

Inputs

Either:

old and new: Two URLs for a single-page check (e.g., https://old.com/page https://new.com/page)
file: Path to CSV/text file with URL pairs, one per line: old_url,new_url

If file provided: Read it and process each line. Skip blank lines and lines starting with #. For large files (>50 URL pairs), process first 50 and note truncation.

Execution

For each URL pair, run checks a-f:

Check a: Redirect Chain Validation

Fetch old URL with WebFetch and follow redirects (track each hop):

Record redirect type: 301 (permanent), 302 (temporary), 307, 308
Count redirect hops
Record final destination URL

Evaluate:

Final destination matches expected new URL: PASS — mismatch: FAIL
Redirect type is 301: PASS — 302/307: WARN (temporary redirects pass less link equity)
Hop count 1: PASS — hop count 2: WARN — hop count >2: FAIL (redirect chain too long)
Direct 200 on old URL (no redirect): FAIL (old page still live, not redirected)

Check b: Canonical Consistency

Fetch new URL, extract <link rel="canonical" href="..."> from <head>.

Canonical matches new URL exactly: PASS
Canonical missing: WARN (Google will infer, but explicit is better)
Canonical points to old URL: FAIL (critical — tells Google old is authoritative)
Canonical points to third URL: WARN

Check c: Title and Meta Preservation

Compare title and meta description between old URL (before redirect) and new URL. Note: old URL may already redirect, so if old URL is not directly fetchable, skip comparison and note.

If comparable:

Title: Extract both. Compare word overlap.
- 70% word overlap: PASS
- 40-70% overlap: WARN (may be intentional change)
- <40% overlap: WARN with note ("significant title change — verify this was intentional")
Meta description: Extract both.
- Present on both: PASS
- Missing on new URL: WARN
- Both missing: NOTE

Check d: HTTP Status

Verify new URL returns 200 OK:

200: PASS
301/302 (new URL also redirects): WARN with destination
404: FAIL
500/5xx: FAIL

Check e: Content Similarity

If both old and new pages are fetchable, compare word counts:

New page word count >= 80% of old: PASS
New page word count 50-80% of old: WARN (possible content reduction)
New page word count < 50% of old: FAIL (significant content loss) If old URL not directly fetchable (already redirects): skip and note.

Check f: Schema Preservation

Extract @type values from JSON-LD blocks on both pages.

Same schema types present: PASS
Schema types reduced: WARN (lost structured data)
Key schema missing on new (e.g., Product, Article, LocalBusiness): WARN
No schema on either: NOTE (not a regression)

Overall Per-URL Result

FAIL: any check is FAIL WARN: no FAILs but any check is WARN PASS: all checks PASS or NOTE

Output Format

## Migration Validation: [old URL] → [new URL]
(or: ## Migration Validation: [N] URL pairs from [filename])

### Summary

| Status | Count |
|--------|-------|
| PASS | N |
| WARN | N |
| FAIL | N |
| Total | N |

### Per-URL Results

| Old URL | New URL | Redirect | Canonical | Title | Meta | Status Code | Schema | Overall |
|---|---|---|---|---|---|---|---|---|
| /old | /new | 301✓ | PASS | PASS | WARN | 200 | PASS | WARN |

### Failed Items Detail

For each FAIL result, expanded information:

**[old URL] → [new URL]**
- Redirect: [issue description]
- Canonical: [issue description]
- [etc.]
- Recommended fix: [specific action]

### Recommendations

[Prioritized list of actions based on failures and warnings]

## Data Sources

- Live URL fetching via WebFetch
- Redirect chain analysis (following HTTP headers)

What ships with it

Read from the repository

Just SKILL.md. No reference files, no scripts.