blog-seo-check

blog-seo-check is a skill for Claude Code from Infrasity-Labs/dev-gtm-claude-skills. It costs 131 tokens per session (2,155 once invoked), scanned A, original, MIT.

A checklist tool that checks a completed blog post for search-engine requirements. SEO means improving a page so search engines can understand and rank it.

In plain words
What is it for?
Use it to validate title tags, meta descriptions, heading structure, keywords, internal and external links, canonical URLs, Open Graph tags, and Twitter Card tags.
Why use it?
It catches publishing problems in titles, descriptions, headings, links, canonical URLs, and social-sharing metadata before the article goes live.

Skill for Claude Code

Written for Claude Code: argument-hint in frontmatter.

Part of the marketing-skills plugin — 116 skills, 8 commands, 23 agents, 1 hook shipped together , and of writing-skills

Good fit Use it to validate title tags, meta descriptions, heading structure, keywords, internal and external links, canonical URLs, Open Graph tags, and Twitter Card tags.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/infrasity-labs/dev-gtm-claude-skills/blog-seo-check
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add Infrasity-Labs/dev-gtm-claude-skills --skill blog-seo-check
Clone the repo
git clone --depth 1 https://github.com/Infrasity-Labs/dev-gtm-claude-skills

Made for: Claude Code.

Or install marketing-skills, the plugin that ships this one along with the rest of its 116 skills, 8 commands, 23 agents, 1 hook.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for blog-seo-check

README.md
[![agentmods](https://agentmods.dev/badge/skills/infrasity-labs/dev-gtm-claude-skills/blog-seo-check/github.svg)](https://agentmods.dev/skills/infrasity-labs/dev-gtm-claude-skills/blog-seo-check)
Your own site
<a href="https://agentmods.dev/skills/infrasity-labs/dev-gtm-claude-skills/blog-seo-check"><img src="https://agentmods.dev/badge/skills/infrasity-labs/dev-gtm-claude-skills/blog-seo-check/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for blog-seo-check

Your own site · 80×15
<a href="https://agentmods.dev/skills/infrasity-labs/dev-gtm-claude-skills/blog-seo-check"><img src="https://agentmods.dev/badge/skills/infrasity-labs/dev-gtm-claude-skills/blog-seo-check.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 131 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,155 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 1 finding, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • medium Output Handling · line 41
    Output size or generation rate is not bounded. Unbounded output enables denial-of-service through resource exhaustion, log flooding, or context-window stuffing.
    Fix: Set explicit limits on output length, generation count, and rate. Use max_tokens and truncation to prevent unbounded output.
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00131 $0.02155
Opus 5 $0.00066 $0.01077
Sonnet 5 $0.00026 $0.00431
Haiku 4.5 $0.00013 $0.00215

Measured 9d ago against content hash 5dc0f4876560, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

blog-seo-check scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.claude/skills/blog-seo-check/SKILL.md · 218 lines

How it starts

The opening of the file, as written. The whole thing — 218 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Blog SEO Check: Post-Writing Validation

Runs a comprehensive on-page SEO validation against a completed blog post and generates a pass/fail checklist with specific fixes for each failure. Designed to run after writing - catches issues before publishing.

Workflow

Step 1: Read Content

Read the target file and extract:

  • Frontmatter - title, description, date, lastUpdated, author, tags, canonical, og:image, slug/URL
  • Heading structure - H1, H2, H3 hierarchy with full text
  • Links - All internal and external links with anchor text
  • Meta tags - OG tags, Twitter Card tags, canonical URL
  • Body content - Full text for keyword and structural analysis

If the user provides a URL instead of a file path, use WebFetch to retrieve the page and extract the relevant elements.

Step 2: Title Tag Validation

Check Pass Criteria
Character count 40-60 characters (no truncation in SERPs)
Keyword placement Primary keyword in first half of title
Power word Contains at least one power word (e.g., Guide, Best, How, Why, Essential, Proven, Complete)
Truncation risk No critical meaning lost if truncated at 60 chars
Uniqueness Not generic - specific to the content

Step 3: Meta Description

Check Pass Criteria
Character count 150-160 characters
Statistic included Contains at least one specific number or data point
Value proposition Ends with clear reader benefit or value proposition
Keyword presence Primary keyword appears naturally (not stuffed)
No keyword stuffing Keyword appears at most once
Call to action Implies action (learn, discover, find out, see)

Step 4: Heading Hierarchy

Check Pass Criteria
Single H1 Exactly one H1 tag (the title)
No skipped levels H1 -> H2 -> H3, never H1 -> H3 or H2 -> H4
Keyword in headings Primary keyword in 2-3 headings (natural, not forced)
Question format 60-70% of H2 headings are questions
H2 count 6-8 H2 sections for a standard blog post
Heading length Each heading under 70 characters

Read the full file on GitHub · 218 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 9d ago First seen · 218 lines · 131 tokens per session scan A 5dc0f4876560

Subscribe to this mod's changes

blog-seo-check is a skill published in the GitHub repository Infrasity-Labs/dev-gtm-claude-skills (124 stars, last pushed 2mo ago), licensed MIT. It adds 131 tokens to every session and 2,155 once invoked, about $0.0007 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

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