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 marketingskills/seo --skill content-decay-monitor-setupgit clone --depth 1 https://github.com/marketingskills/seoWrote 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/marketingskills/seo/content-decay-monitor-setup)<a href="https://agentmods.dev/skills/marketingskills/seo/content-decay-monitor-setup"><img src="https://agentmods.dev/badge/skills/marketingskills/seo/content-decay-monitor-setup/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/marketingskills/seo/content-decay-monitor-setup"><img src="https://agentmods.dev/badge/skills/marketingskills/seo/content-decay-monitor-setup.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 | $0.00041 | $0.00255 |
| Opus 5 | $0.00020 | $0.00128 |
| Sonnet 5 | $0.00008 | $0.00051 |
| Haiku 4.5 | $0.00004 | $0.00026 |
Grade A, and why
content-decay-monitor-setup 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.
What it actually says
Content Decay Monitor Setup
Overview
Configure a recurring monitor that checks a list of pages or topics for organic performance changes. The monitor runs on a schedule (weekly/monthly) and alerts when performance drops below a threshold.
Inputs
- List of URLs or topics to monitor
- Monitoring frequency (weekly, biweekly, monthly)
- Alert threshold (e.g., 15% click decline, 20% impression drop)
- Optional: GSC property or GA4 property
Workflow
- Define the monitor scope: pages, topics, or both.
- Set baseline performance from current GSC/GA4 data.
- Configure the check frequency and alert threshold.
- Store the monitor configuration in a local file or agent config.
- On each check cycle: fetch current data, compare to baseline, flag pages below threshold.
- Route alerts to the user (with traffic-decay-detector for deeper analysis).
Output
Monitor configuration file and recurring check instructions for the agent runtime.
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 · 31 lines · 41 tokens per session scan A 1572e3e93653
content-decay-monitor-setup is a skill published in the GitHub repository marketingskills/seo (3 stars, last pushed 1mo ago), licensed MIT. It adds 41 tokens to every session and 255 once invoked, about $0.0002 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 2026-08-31.
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