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 schema-fix-writergit 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/schema-fix-writer)<a href="https://agentmods.dev/skills/marketingskills/seo/schema-fix-writer"><img src="https://agentmods.dev/badge/skills/marketingskills/seo/schema-fix-writer/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/schema-fix-writer"><img src="https://agentmods.dev/badge/skills/marketingskills/seo/schema-fix-writer.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 | $0.00040 | $0.00280 |
| Opus 5 | $0.00020 | $0.00140 |
| Sonnet 5 | $0.00008 | $0.00056 |
| Haiku 4.5 | $0.00004 | $0.00028 |
Grade A, and why
schema-fix-writer 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 11d 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
Schema Fix Writer
Overview
Given a page URL and its content, analyze what schema types would be appropriate and propose specific JSON-LD or microdata changes. Uses the page type (article, product, FAQ, how-to, local business, etc.) and current SERP features to determine the best schema strategy.
Inputs
- Page URL and optionally its rendered content
- Current schema (if any) — paste from source or tool output
- Page type or topic
Workflow
- Determine the page type from content analysis.
- Check the page's current schema markup for errors or missing fields.
- Research the target SERP for rich result types present.
- Propose schema changes:
- Add missing schema type for the page type
- Fix validation errors in existing schema
- Add relevant properties (review, FAQ, how-to steps, etc.)
- Remove deceptive or irrelevant markup
- Write the JSON-LD or microdata snippet.
- Include testing instructions (Schema.org validator, Rich Results Test).
Output
Schema recommendation with proposed markup, validation notes, and SERP eligibility impact.
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.
- 11d ago First seen · 34 lines · 40 tokens per session scan A 356d3f06caa6
schema-fix-writer is a skill published in the GitHub repository marketingskills/seo (3 stars, last pushed 1mo ago), licensed MIT. It adds 40 tokens to every session and 280 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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