yuin/goldmark is a Markdown parser written in Go that converts Markdown into structured output such as HTML while supporting CommonMark and custom syntax extensions. Developers use it to process, analyze, and generate Markdown in Go applications and tools. The catalogue add-ons provide agent instructions and integrations for working with the parser.
Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/yuin/goldmarknpx agentmods add skills/yuin/goldmark/migrate-goldmark-app-v1-to-v2Wrote 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/yuin/goldmark/migrate-goldmark-app-v1-to-v2)<a href="https://agentmods.dev/skills/yuin/goldmark/migrate-goldmark-app-v1-to-v2"><img src="https://agentmods.dev/badge/skills/yuin/goldmark/migrate-goldmark-app-v1-to-v2/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/yuin/goldmark/migrate-goldmark-app-v1-to-v2"><img src="https://agentmods.dev/badge/skills/yuin/goldmark/migrate-goldmark-app-v1-to-v2.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00025 | $0.01095 |
| Opus 5 | $0.00013 | $0.00548 |
| Sonnet 5 | $0.00005 | $0.00219 |
| Haiku 4.5 | $0.00003 | $0.00110 |
Grade A, and why
migrate-goldmark-app-v1-to-v2 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 — 90 lines — stays where its author put it; the contents beside it link to each section on GitHub.
migrate-goldmark-app-v1-to-v2
Description
This skill helps you migrate a goldmark (https://github.com/yuin/goldmark) extension from version 1 to version 2. It provides guidance on the changes needed to update your project to be compatible with the new version of goldmark.
Knowledges
- CommonMark key points : List of key points of CommonMark spec that you should be aware of when implementing a goldmark extension.
- Breaking changes in v2 : List of breaking changes in goldmark v2 that you should be aware of when migrating your extension from v1 to v2.
Migration steps
Overview of the migration process
- Create a migration plan for the application.
- MUST ask human to confirm that the migration plan is acceptable before proceeding with the migration.
- MUST ask human to how to test the application after migration before proceeding with the migration.
- e.g. : "How do you want to test the application after migration? Do you have any test cases or examples that you want to use for testing?"
- Execute the migration plan to update the application code to be compatible with goldmark v2.
- Update the test cases to ensure that the application works as expected with goldmark v2.
- Test the application with goldmark v2 to ensure that it works as expected. If there are any issues, fix them and re-test until the application works as expected.
- Update the documentation to reflect any changes made during the migration process.
Create a migration plan
Task
- Make sure you have read and understood the Breaking changes in v2 document.
- Make sure you have read and understood the How to create an extension document.
- You create a ./features/goldmark-migration-plan.md file that contains a migration plan for the extension.
Extension
- If the application contains own extensions, you can use
/migrate-goldmark-extension-v1-to-v2skill to migrate the extensions. - If the application contains third-party extensions, you need to check if the extensions provide v2 compatible version. - If not, STOP the migration.
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 · 90 lines · 25 tokens per session scan A c040b497bd87
migrate-goldmark-app-v1-to-v2 is a skill published in the GitHub repository yuin/goldmark (5,008 stars, last pushed yesterday), licensed MIT. It adds 25 tokens to every session and 1,095 once invoked, about $0.0001 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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