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.
npx skills add lionkiii/claude-seo-skills --skill seo-gsc-content-decaygit clone --depth 1 https://github.com/lionkiii/claude-seo-skillsWrote 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.
[](https://agentmods.dev/skills/lionkiii/claude-seo-skills/seo-gsc-content-decay)<a href="https://agentmods.dev/skills/lionkiii/claude-seo-skills/seo-gsc-content-decay"><img src="https://agentmods.dev/badge/skills/lionkiii/claude-seo-skills/seo-gsc-content-decay/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.
<a href="https://agentmods.dev/skills/lionkiii/claude-seo-skills/seo-gsc-content-decay"><img src="https://agentmods.dev/badge/skills/lionkiii/claude-seo-skills/seo-gsc-content-decay.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00082 | $0.01350 |
| Opus 5 | $0.00041 | $0.00675 |
| Sonnet 5 | $0.00016 | $0.00270 |
| Haiku 4.5 | $0.00008 | $0.00135 |
Grade A, and why
seo-gsc-content-decay 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 12d 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.
How it starts
The opening of the file, as written. The whole thing — 135 lines — stays where its author put it; the contents beside it link to each section on GitHub.
GSC Content Decay — 90-Day Decline Detection
@skills/seo/references/mcp-degradation.md @skills/seo/references/gsc-api-reference.md
Identifies pages experiencing true content decay: both clicks AND impressions declining over a 90-day comparison period. Filters out seasonal variation by requiring both metrics to decline simultaneously.
MCP Check
Before calling any GSC tool, verify the MCP is connected:
- Use ToolSearch with query
+google-search-console - If tools returned — note the actual tool name prefix, proceed to Inputs
- If no tools returned — display the GSC MCP error template from
references/mcp-degradation.mdand stop:
## Google Search Console MCP Not Available
The `/seo gsc content-decay` command requires the GSC MCP, which is not currently connected.
**What you can do:**
- Use `/seo technical <url>` for crawlability and indexability analysis (no live data)
- Use `/seo audit <url>` for a full static SEO audit
**To connect GSC MCP:**
- Install and configure a Google Search Console MCP server (see README for setup)
- Add it to ~/.claude/mcp.json at user scope (NOT project scope)
- Verify GSC property access before running commands (domain vs URL prefix format)
- See references/gsc-api-reference.md for property format details
Inputs
site: The GSC property URL. Accept both formats:- Domain property:
sc-domain:example.com - URL prefix:
https://example.comorhttps://www.example.com - If user provides a bare domain (no prefix), call
list_sitesto identify the correct property format registered in GSC.
- Domain property:
Date Calculation
Use Bash to calculate 90-day comparison windows (GSC has ~3 day delay):
currentEnd=$(date -v-3d +%Y-%m-%d)
currentStart=$(date -v-93d +%Y-%m-%d)
previousEnd=$(date -v-93d +%Y-%m-%d)
previousStart=$(date -v-183d +%Y-%m-%d)
echo "Current: $currentStart to $currentEnd | Previous: $previousStart to $previousEnd"
Execution
Call compare_performance with 90-day window:
siteUrl: the site propertycurrentStartDate: currentStartcurrentEndDate: currentEndpreviousStartDate: previousStartpreviousEndDate: previousEnddimension:"page"limit: 1000
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.
- 12d ago First seen · 135 lines · 82 tokens per session scan A 38a2209b2038
seo-gsc-content-decay is a skill published in the GitHub repository lionkiii/claude-seo-skills (20 stars, last pushed 3mo ago), licensed MIT. It adds 82 tokens to every session and 1,350 once invoked, about $0.0004 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 2026-08-30.
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