SEO Drift Monitor

Protect your SEO work from being broken by page changes. Baseline a page, detect regressions, get fix recommendations.

Commands

Command	Description
`/seo-drift baseline <url>`	Capture a "known good" snapshot of all SEO-critical elements
`/seo-drift check <url>`	Compare current state against the most recent baseline
`/seo-drift history <url>`	Show all baselines and checks for a URL

Baseline Workflow

When the user runs /seo-drift baseline <url>:

Run the baseline capture script:

python3 ~/.claude/skills/seo-drift/scripts/baseline.py "<url>"

Parse the JSON output and present a formatted summary:

Baseline saved for [domain] (ID: [id])

Title: [title]
H1: [h1 text] ([h1_count] total)
Schema: [schema_count] blocks ([schema_types])
Canonical: [canonical]
Robots: [robots or "none"]
OG Tags: [og_tags count]
CWV: [score]/100 (LCP: [lcp]s, FCP: [fcp]s, CLS: [cls])

If the script returns an error, display it and suggest fixes.

Optional flags:

Add --skip-cwv to skip the PageSpeed Insights API call (faster)

Check Workflow

When the user runs /seo-drift check <url>:

Run the check script:

python3 ~/.claude/skills/seo-drift/scripts/check.py "<url>"

Parse the JSON output. If there's an error about no baseline, tell the user to run /seo-drift baseline <url> first.

Present diffs grouped by severity:

Drift Check for [domain]
Baseline: [baseline_date] | Checked: [checked_at]

CRITICAL ([count]):
- [element]: [before] -> [after]
  Fix: [recommendation]

WARNING ([count]):
- [element]: [before] -> [after]
  Fix: [recommendation]

INFO ([count]):
- [element]: [before] -> [after]

Report: [report_path]

For CRITICAL and WARNING diffs, cross-reference the appropriate claude-seo skill:
- Schema issues -> recommend /seo-schema to regenerate
- CWV regressions -> recommend /seo-technical for diagnosis
- Content/heading issues -> recommend /seo-page for analysis
- Meta tag issues -> recommend /seo-page for review
If a report was generated, tell the user they can open it in a browser.

History Workflow

When the user runs /seo-drift history <url>:

Run:

python3 ~/.claude/skills/seo-drift/scripts/history.py "<url>"

Replace <url> with the actual URL.

Present as a timeline:

History for [domain]:

Baselines:
#[id]  [date]  Title: "[title]"  Schema: [count] blocks  CWV: [score]/100
#[id]  [date]  Title: "[title]"  Schema: [count] blocks  CWV: [score]/100

Checks:
#[id]  [date] vs baseline #[baseline_id]  [critical]C [warning]W [info]I

Severity Classification

Change	Severity	Why It Matters
Schema block removed	CRITICAL	Removes rich snippets from SERPs
Canonical changed/removed	CRITICAL	Can cause deindexing or duplicate content
robots noindex added	CRITICAL	Removes page from Google entirely
H1 removed or changed	CRITICAL	Primary ranking signal for the page
Title removed	CRITICAL	Most important on-page SEO element
Status code -> 4xx/5xx	CRITICAL	Page is inaccessible
Title text changed	WARNING	May affect click-through rate
Description changed	WARNING	Affects SERP snippet appearance
CWV regression >20%	WARNING	Core Web Vitals affect rankings
OG tags removed	WARNING	Affects social media sharing
Schema content modified	WARNING	May invalidate rich results
H2/H3 structure changed	INFO	Minor structural change
Content hash changed	INFO	Page text was updated

Data Storage

Database: ~/.claude/seo-drift/baselines.db (SQLite)
Reports: ~/.claude/seo-drift/reports/

Dependencies

This skill requires:

Python 3.10+
requests (for HTTP fetching)
beautifulsoup4 (for HTML parsing)
curl (for PageSpeed Insights API)

Install: pip install requests beautifulsoup4

Integration with claude-seo

This skill extends the claude-seo ecosystem by adding a defensive monitoring layer. While other seo-* skills optimize pages, seo-drift protects what's already optimized:

Uses seo/scripts/fetch_page.py for HTTP fetching with SSRF prevention
Uses seo/scripts/parse_html.py for SEO element extraction
Recommends seo-schema, seo-technical, and seo-page skills for fixing detected issues

seo-drift