Agent skill · marketing growth · kostja94
canonical-tag
When the user wants to configure canonical URLs, fix duplicate content, or consolidate URL signals. Also use when the user mentions "canonical," "canonical URL," "duplicate content," "duplicate content fix," "preferred URL," or "URL consolidation." For GSC duplicates, use google-search-console.
Why this skill is useful
Provides specific implementation patterns and methods for configuring canonical URLs, which the AI may not reliably generate on its own.
What it needs
About 2k tokens when loaded. Last updated 2026-06-09. 860 stars on the source repository.
What this skill does
SEO Technical: Canonical Guides canonical tag configuration to consolidate duplicate content and declare preferred URLs. When invoking: On first use, if helpful, open with 1–2 sentences on what this skill covers and why it matters, then provide the main output. On subsequent use or when the user asks to skip, go directly to the main output. Scope (Technical SEO) Duplicate site versions: HTTPS vs HTTP; www vs non-www; trailing slash (/page vs /page/) — choose one, 301 redirect others Duplicate content: Canonical tags; consolidate and 301 to preferred URL HTTPS: SSL/TLS; secure connection; ranking signal since 2014 Initial Assessment Check for project context first: If .claude/project-context.md or .cursor/project-context.md exists, read it for site URL and language structure. Identify: 1. Site URL: Base domain 2. Duplicate scenarios: Multi-language, query params, pagination, alternate URLs 3. Framework: Next.js, React, static, etc. Canonicalization Methods (Choose by Scenario) Method When Strength -------- ------ ---------- 301 redirect Preferred; server can redirect Strongest — permanent redirect Canonical tag Cannot redirect (e.g. params, pagination) Strong — HTML signal robots.txt Block non-canonical paths Weak — advisory only Use 301 for HTTP→HTTPS, www variants, trailing slash. Use canonical for params, pagination, UTM. HTTPS & Security HTTPS is a ranking signal (Google, 2014). Users and crawlers should access only the HTTPS version. Requirement Action ------------- -------- SSL/TLS certificate Install valid certificate; use Let's Encrypt for free 301 redirect HTTP → HTTPS; all HTTP requests redirect to HTTPS Mixed content No HTTP resources on HTTPS pages; fix mixed content warnings HSTS Optional; Strict-Transport-Security header for repeat visitors WWW vs non-WWW: Choose one preferred version; 301 redirect the other. See canonical rules above. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills kostja94/canonical