ig-carousel

Carousels are the highest-dwell format on the grid, because a swipe is an interaction and a scroll is not. They also get a second chance: Instagram can show a carousel again starting from a later slide to someone who did not engage the first time, so slide two has to stand on its own as well.

The format rewards one idea broken into steps. It punishes a caption cut into pieces.

When to use it instead of a Reel

Use a carousel when the idea has sequence and needs to be re-read: steps, a framework with parts, a before and after, a list worth screenshotting. Use a Reel when the idea has motion, a face, or a payoff that has to be seen happening.

If the idea is one claim, it is neither. Hand it to /ig-reel and say so.

Structure

6 to 10 slides. The cap is 20 and 20 is almost always a book nobody finishes. Under 5 and the swipe never starts.

1         COVER     the hook. 6 words or fewer, at a size that is legible in
                    the grid at thumbnail. One line of promise under it.
2         THE STAKE why this matters, in one sentence. This slide is also a
                    second cover, so it cannot be setup.
3 to N    ONE IDEA PER SLIDE. A headline of 3 to 7 words, at most 25 words
                    under it. If a slide needs a paragraph, it is two slides.
N+1       RECAP     the whole thing as a list. This is the screenshot slide.
LAST      CTA       one action. Save, comment a keyword, or follow. One.

Slide copy rules

• The cover is 80% of the result. Six words. Big. Nothing on the deck saves a cover nobody swipes.
• Design for the grid crop. The profile grid crops to a portrait rectangle that is taller than it is wide, and the exact ratio has moved more than once. Build at 1080x1350 and keep the cover text well inside the middle, clear of the outer 120 pixels on every side, and the crop stops mattering.
• Number the slides (3/8). Completion goes up when people can see the end.
• No slide is a paragraph. If it cannot be said in 25 words, split it.
• The recap slide is the one people screenshot and send. Sends are the strongest signal you can earn. Make it standalone and readable with no context.
• The handle on every slide, small, bottom corner. Screenshots travel without you.
• Alt text on the cover at minimum. It is read by screen readers and by Instagram.

Building the files

Instagram wants 1080x1350 (4:5), JPEG or PNG, up to 20 items. Build it as HTML and print each slide:

# one <section> per slide, 1080x1350, page-break-after: always
# then Chrome headless --print-to-pdf, or any HTML-to-image you already use

Write the HTML with width:1080px; height:1350px, a single accent colour, and type no smaller than 32px, because this is read on a phone at a third of its real size. If the project has a brand skill or a design system, use it and do not invent a palette.

Output

The slide-by-slide copy first, as a numbered list the user can read in ten seconds and edit before anything is rendered. Then the caption, which for a carousel is Job B in /ig-caption: the caption is doing work here, because the cover has already used its six words.

Run both through /ig-human. Build the files only after the user approves the copy.

CAROUSEL  ·  8 slides

1  COVER   THE $18,000 CLAUSE
           One line I now put in every contract.
2  STAKE   I approved the work. They asked for the money back nine days later.
3          WHAT IT SAYS
           Payment on delivery, not on approval.
...
7  RECAP   All four lines, in order.
8  CTA     Comment CONTRACT and I will send the full clause.

Caption: Job B, hook in line 1, one ask, 3 tags.

Nothing is uploaded by this skill. Once the copy is approved and the files are rendered, there are two ways out:

• PostZen connected (the createPost and createMediaPresign tools are in this session): offer /ig-publish with postType: "carousel". It uploads each slide, in order, and the caption rides along as content. Three things to know before offering it: the API takes 2 to 10 items, so a deck past 10 is a manual post; export the slides as JPEG, because PostZen does not convert PNG for Instagram; and the API does not carry alt text or photo tags on carousels, so alt text on the cover is added in the app afterwards. The user confirms the full post there before anything goes out.
• Not connected: the user posts it by hand, as before.