| name | x-article |
| description | Convert a posthog.com blog or newsletter post into a markdown file formatted for posting as an X (Twitter) Article. Strips frontmatter, promotes the title to an H1, remaps headings to X's two heading levels (subheadings + bold), downloads all post images into a numbered folder, and appends a subscribe CTA for newsletters. Use when the user wants to copy a post from contents/blog/ or contents/newsletter/ into X Article format. |
Format a post for an X Article
X Articles only support two heading levels ("heading" and "subheading") plus bold text, and images must be uploaded one at a time. This skill produces a clean markdown file and a folder of ordered images so the user can copy/paste text and drag images in order.
The user will provide a post — a slug, a filename, or a path under contents/blog/ or contents/newsletter/: $ARGUMENTS
Step 1: Locate the source
Find the source file under contents/blog/ or contents/newsletter/ (extension may be .md or .mdx). If the argument is ambiguous or matches multiple files, ask which one. Note whether it came from blog or newsletter — the CTA in Step 4 only applies to newsletters.
Read the full file.
Step 2: Set up the output
Derive {slug} from the source filename (without extension). Create the output folder x-articles/{slug}/ (relative to repo root) and an images/ subfolder inside it.
Step 3: Write x-articles/{slug}/article.md
Transform the source body into the article file:
-
Remove the frontmatter (everything between the opening and closing ---).
-
Remove MDX import lines and any other JSX/component noise that won't render as plain text (e.g. <NewsletterForm />, <ProductComparisonTable .../>, wrapping <div>s). If a component can't be represented as text, drop it. Images inside components are still handled in Step 4.
-
Title → H1. Take the title from the frontmatter and put it as a single # Title at the very top of the file.
-
Remap headings (because X collapses everything to two levels):
## → #
### → ##
#### Heading → **Heading** (bold paragraph, heading text only)
- Leave
#####+ as bold too.
-
Keep all body text, links, lists, blockquotes, code blocks, and footnotes verbatim. X has no relative-link context, so prefix any relative links (e.g. /blog/..., /feature-flags) with https://posthog.com.
-
Replace each image with a numbered marker. Walk the body top to bottom and replace every image (see Step 4 for what counts as an image) with a line like:
[IMAGE 1: alt text]
Numbered in document order starting at 1. This tells the user which downloaded image goes where.
Step 4: Download the images
Collect every image URL in document order. Images appear as:
- Markdown:

- Components:
imageLight="https://res.cloudinary.com/..." (and imageDark= — prefer imageLight; skip the dark duplicate)
- Raw
<img src="...">
Cloudinary URLs may contain transformation segments between /upload/ and the filename (e.g. /upload/q_auto,f_auto/file.jpg or /upload/w_1600,c_limit,q_auto,f_auto/file.jpg). Download the URL as-is — the transformations are harmless.
Do not download the featuredImage from frontmatter unless it also appears in the body.
For each image in order, save it to x-articles/{slug}/images/{n}.{ext} where {n} matches the [IMAGE n: ...] marker and {ext} is the original extension from the URL (jpg, png, gif, webp). Download with:
curl -sSL -o "x-articles/{slug}/images/{n}.{ext}" "{url}"
Run the downloads and verify each file is non-empty (a failed Cloudinary fetch returns a tiny error body). Report any that failed.
Step 5: Newsletter CTA
If — and only if — the source was a newsletter, append this to the very bottom of article.md:
> [Subscribe to Product for Engineers](https://newsletter.posthog.com/subscribe), our newsletter, to get more writing like this.
Step 6: Report
Tell the user:
- The output path
x-articles/{slug}/article.md
- How many images were downloaded (and where), and flag any failures
- A reminder that
[IMAGE n: ...] markers in the text show where each numbered image goes