SEO Onpage Skill for Claude

On-Page SEO

Optimize a single page for search relevance, click-through, and crawler comprehension. Stack-agnostic. Works on any CMS, framework, or static site.

When to use

• Auditing or optimizing a single page (homepage, product page, article, landing page)
• Writing or reviewing title tags and meta descriptions
• Fixing header structure or content hierarchy
• Reviewing internal links from or to a page
• Improving a page's CTR from search results

When NOT to use

• Site-wide crawl, indexing, or speed issues (use seo-technical)
• Keyword research or intent mapping (use seo-keyword)
• Competitor SERP analysis (use seo-competitor)
• Auditing many pages at once for prune/merge decisions (use seo-content-audit)

Required inputs

• The page URL or the draft content if pre-launch
• The primary target query (one phrase the page should rank for)
• The page's role in the site (commercial, informational, navigational)

If the target query is unknown, run seo-keyword first or ask the user to name one.

The framework: 8 dimensions

A complete on-page audit covers eight dimensions. Score each as Pass, Needs work, or Fail. Note the specific fix.

1. Title tag

• One unique title per URL across the site
• Roughly 50 to 60 characters (longer gets truncated in SERPs)
• Primary query near the front
• Brand at the end if it earns inclusion
• Distinct from the H1 (often very similar, but should not be identical word-for-word)

2. Meta description

• One unique description per URL
• Roughly 150 to 160 characters
• Restates the value proposition, not the title
• Includes a soft CTA where natural
• Treats the description as ad copy that earns the click

3. Header structure

• Exactly one H1 per page
• H1 contains or paraphrases the primary query
• H2 sections cover the major sub-topics
• H3+ used only when an H2 has genuine sub-points
• No skipped levels (no H2 followed by H4)
• Headers describe sections accurately enough that a reader could navigate by them alone

4. Body content

• Opens with the primary user intent answered in the first paragraph
• Covers the topic comprehensively (define your competition's depth, then match or exceed it)
• Includes related entities and supporting concepts naturally
• Avoids keyword stuffing (write for the reader, not the bot)
• Reading level matches the audience (run a readability check)
• Paragraphs short enough to scan on mobile (3 to 5 lines)

5. Internal links

• At least 2 to 3 outbound internal links to closely related pages
• At least 2 to 3 inbound internal links from related pages
• Anchor text is descriptive, not "click here" or "learn more"
• Links to canonical URLs, not redirects
• No broken internal links

6. Images and media

• Every meaningful image has descriptive alt text (skip alt for purely decorative images)
• File names are descriptive ("blue-running-shoe.jpg" not "IMG_4032.jpg")
• Modern format used where supported (WebP, AVIF)
• Lazy loading on below-the-fold images
• Width and height attributes set to prevent layout shift

7. URL slug

• Lowercase, hyphen-separated
• Includes the primary query naturally (no stuffing)
• Short (under 60 characters where possible)
• No dates unless the page is genuinely time-bound
• No session IDs, tracking parameters, or random hashes
• Matches the site's URL pattern conventions

8. On-page schema

• Appropriate Schema.org type for the content (Article, Product, FAQPage, HowTo, Recipe, etc.)
• Required properties filled (review Schema.org docs for the type)
• Validates in Google's Rich Results Test or equivalent
• Matches what is visible on the page (do not lie to crawlers)
• Author and publisher schema linked correctly for content pages

Workflow

• Confirm the target query. If unclear, ask. Do not optimize without one.
• Render the page. View it as a user would. Read the content top to bottom.
• View the rendered HTML. Inspect the actual served markup, not just the visual page. Check <title>, <meta>, headers, and schema in the source.
• Run the 8-dimension framework. Score each, note specific fixes.
• Prioritize. Group fixes into Critical (broken or missing), Important (suboptimal), and Nice-to-have (polish).
• Write the report. Use the template in references/audit-template.md.
• Offer to draft fixes. If the user wants, draft the new title, meta, headers, or copy directly.

Failure patterns

When you spot one of these, push back before delivering.

• "Make it more SEO." Vague. Ask for the target query and what's broken first.
• "Add the keyword 5 times in the body." Keyword density is not a real ranking signal. Prioritize relevance and topical depth instead.
• Optimizing a page that is not crawlable or indexable. Check seo-technical first. No on-page work helps a noindexed page.
• Optimizing a page with no clear user intent. A page that does not serve a real query will not rank no matter how well-tagged it is.
• Targeting the same query as another page on the site. This is cannibalization. Use seo-content-audit to decide which page should rank.

Output format

Default output is a markdown audit at seo-audit-[page-slug].md in the project root. Structure:

• Page summary (URL, target query, role)
• Score across 8 dimensions
• Critical fixes
• Important fixes
• Nice-to-have polish
• Drafted replacements (if requested)

Keep audits under 1500 words. If a page needs more detail, link to deeper appendices.

Reference files

• references/audit-template.md - Fillable audit template, copy and use.
• references/onpage-checklist.md - Quick-reference checklist for the 8 dimensions.
• references/title-and-meta-patterns.md - Patterns for writing strong titles and meta descriptions.