Canonical Tag Audit Claude Skill
This skill audits a website's rel="canonical" tags and produces an actionable report. It crawls pages and probes each canonical target to find missing canonicals, multiple conflicting canonicals, canonicals pointing at non-200, redirecting, or noindexed URLs, relative (non-absolute) canonicals, cross-host canonicals, https-to-http protocol downgrades, conflicts between the HTTP Link header and the in-page canonical, and canonicals that contain fragments.
Quick Take
Point the skill at a site root or URL list. It crawls pages, extracts every canonical signal, probes each target's status, redirect, and noindex state, runs the checks across severity tiers, and returns a prioritized report with targeted fixes.
What The Skill Checks
- Presence and uniqueness: pages missing a canonical, pages with multiple conflicting canonicals, and conflicts between the HTTP Link header canonical and the in-page tag.
- Target health: canonicals pointing at non-200, redirecting, or noindexed URLs, all of which break duplicate-content consolidation.
- Format correctness: relative (non-absolute) canonicals, cross-host canonicals, https-to-http protocol downgrades, and canonicals containing URL fragments.
How The Skill Is Packaged
The skill follows the standard Claude Agent Skill structure: a SKILL.md file with YAML frontmatter and workflow instructions, a references/ folder with the full audit check definitions and report template, and a scripts/ folder with Python scripts that crawl the site and extract canonical signals, then probe each canonical target and audit the resulting inventory. Install it with npx claude-seo-skills install canonical-tag-audit, or copy the skill folder into your Claude skills directory; Claude invokes it automatically when a request matches its description.
Skill Files
Every file in the skill is embedded below directly from the Claude-SEO-Skills repository, so you can review exactly what the skill instructs Claude to do before installing it.
SKILL.md
The skill definition: frontmatter, inputs to collect, the workflow, and the resources the skill relies on.
Audit Checks Reference (references/audit-checks.md)
Full definitions, severities, and rationale for every check across the high, medium, and low tiers.
Report Template (references/report-template.md)
The output structure the skill follows, including the sections issues are grouped into.
Canonical Extractor Script (scripts/extract_canonicals.py)
Crawls pages and extracts every rel=canonical signal, including in-page tags and HTTP Link headers.
Canonical Auditor Script (scripts/audit_canonicals.py)
Probes each canonical target for status, redirects, and noindex, then runs the audit checks and outputs the structured report data.