| name | instagram-post |
| description | Write Instagram content — Reels, carousels, single feed cards, and Stories — as production-ready specs with card-by-card text, the visible first line, caption, alt text and hashtags. Use when the user says 'Instagram post,' 'Instagram Reel,' 'IG carousel,' 'Instagram carousel,' 'instagram caption,' 'IG Stories,' 'Instagram alt text,' or otherwise names Instagram as the channel. Instagram only: if the user says 'carousel,' 'slide-by-slide,' 'feed post,' 'Stories' or 'Reel' without naming a platform, ask which platform first — route LinkedIn/X/Facebook carousels, document posts and any cross-platform posting plan to `social`, TikTok to tiktok-script, Shorts to youtube-shorts. A Reel is not a TikTok and not a Short. Covers which format to pick, the carousel card architecture, why sends (not saves) are the ranking currency, alt text as a first-class deliverable, and link handling when caption URLs do not click. |
| metadata | {"version":"1.1.0"} |
Instagram
The currency is the send, not the save. This is the most commonly mis-stated fact about the platform, and it is worth getting right before anything else.
Adam Mosseri stated on his own Instagram in January 2025, and has restated since, that Instagram runs two ranking regimes — connected reach (your followers) and unconnected reach (everyone else) — and that for both, the top three signals are watch time, likes, and sends. His nuance: likes matter slightly more than sends for connected content; sends matter slightly more than likes for unconnected content; watch time is the most important for both.
So if the goal is reaching people who do not follow you — which is the goal for a small account — the question to ask of every post is: would somebody DM this to one specific person? Not "would somebody like this", and not "would somebody save this". A save is a private bookmark; a send is a small act of social risk on your behalf, and it is the strongest thing a stranger's feed can tell the ranking system about you.
Mosseri's second point matters as much: judge engagement rate, not raw reach — of the people who saw it, how many acted. A post shown to fewer people that converts a higher share of them is the better post, and reach alone will tell you the opposite.
Saves still matter, and content with re-read value is still the right instinct for a small brand. But optimise the shareable version of that instinct: the card someone forwards to a friend who has the problem.
Numbers and platform statements in this file were verified 2026-08-26. Ranking guidance moves; re-check before betting a quarter on it.
Read first
If .agents/brand-context.md exists, read it — the claim ledger, prohibited-language list and
channel CTA policy. If it does not, do not stop: derive what you need from the codebase as you
draft, and run claim-check on the finished draft, which builds the ledger properly.
Pick the format first
| Format | Use it when | What it earns |
|---|
| Carousel | The idea has 4–6 discrete steps or a before/after comparison | Sends and saves — the format people forward |
| Reel | The idea needs motion, or the proof is something happening | Reach, via watch time |
| Single card | One sentence carries the whole post | Follows, when it is a position rather than a tip |
| Story | Ephemeral, conversational, or a poll | Nothing durable — use for the audience you already have |
A common and correct pattern: Reels bring people in, carousels make them stay. Alternate.
The deliverable
- **Segment:** who this is aimed at
- **Gate:** SHIP / NEEDS-ASSET / HELD-<reason>
- **Asset:** exact spec — 4:5 is 1080×1350, Reel is 1080×1920
- **CTA:** the link policy for this post (often: none)
**First line (pre-"more"):** the one sentence visible before the caption truncates
**Card text:** numbered, title + subtitle per card
**Caption:** the essay
**Alt text:** a real description
**Hashtags:** 3–5
The gate matters as much as the copy. An Instagram post that announces a change cannot go out while the change is only planned — check the live site, not a preview build, and if only part of the change shipped, cut the caption down to the part that did.
Carousel architecture
Five to six cards. Each card is a title plus one subtitle line — a card that needs a paragraph is a caption in disguise.
The shape that works for an explanatory carousel:
- The claim, stated flat. No wind-up.
Three observations. Max.
- The specifics. The numbers, the constraint, where it comes from.
- The turn. Why this is not the obvious thing the reader assumed —
This isn't minimalism.
- The proof. A real screenshot, a real diff, a real comparison. Not an illustration of proof.
- The rule. The one line worth screenshotting:
If you can't check it against the frame, it isn't a clue.
- The close. Brand line, boundary statement, no CTA.
Card 4 is where most carousels fail. A generated image of a thing is not evidence of the thing — if the card is claiming a fact about your product, it should be a screenshot of your product.
Design consistency does more work here than design quality: one ground colour, one accent, one border treatment, held across every carousel, so a returning viewer recognises the account before they read a word.
The visible first line
Instagram truncates at roughly 125 characters. Write that line deliberately and put it in the spec, because it is the only caption most people read.
It should be the claim, not a hook and not a greeting:
There is a hard cap of three observations per reading.
Not "Ever wondered how many observations we show?"
The caption
Longer than TikTok's, and doing different work: the caption is where the account develops a voice people follow. Four to six short paragraphs.
- Open with the claim (the same line as above).
- Give the specifics with their source.
- Then the interesting part: why. The decision, the constraint, the thing you rejected. This is what carousel savers came back for.
- Land the rule.
- Sign it. One name, consistently, across every post and every other channel.
Instagram tolerates — rewards, even — a genuinely reflective register that TikTok would scroll past. Use it. This is the channel where "here is a decision we made and the reasoning behind it" outperforms a tip.
Alt text is a deliverable, not an accessibility checkbox
Write it for someone who cannot see the image and describe what is actually there, including the design, then the text on the cards. It is also the only machine-readable description of a carousel that exists, which makes it the layer that determines whether the post is retrievable at all.
A six-card carousel in cream, cocoa brown, butter yellow and mint, with thick outlines and hard
drop shadows. The cards read: "Three observations. Max."; "Title: 3 words. Detail: 10 words."; …
Links
Caption URLs are not clickable. The link lives in the bio, and the caption says "Link in bio" only when there is a link worth clicking and attribution is actually deployed.
If attribution is not working, do not use tracked URLs anywhere. A tracked link that nothing reads produces a false sense of measurement. Run plain bio links and read native insights until an end-to-end attribution test passes.
When you do run tracked bio links, hold one URL for the whole run. Swapping in a post-specific URL misattributes every later click from the older post. Native post analytics already distinguish the posts; the bio link measures the cohort.
Reels
A Reel is not a Reel-shaped TikTok. Same aspect ratio, different audience posture:
- Slightly more polished. TikTok rewards raw; Instagram rewards considered. Not corporate — considered.
- Watch time is the top-weighted signal, so the hook still has to land, but the payoff matters more here than on TikTok: a viewer who stays to the end is worth more than one who was startled into two seconds.
- Write for the rewatch. Reels loop. A video that ends where it began earns a second view for free.
- Captions on screen, always. Most viewing is silent.
- The Reel's caption still does the essay job above; do not let the video carry the whole argument.
Length, measured rather than asserted. Socialinsider's 2026 study of ~140K business-account Reels (Jan–Jun 2026) puts reach rate by duration at:
| Duration | Reach rate |
|---|
| under 30s | 5.20% |
| 30–60s | 5.60% |
| 60–90s | 5.30% |
| 90–120s | 4.30% |
| over 120s | 3.50% |
Reach falls monotonically past 60 seconds. 30–60s is the measured optimum — a genuine finding, and the opposite of the "go longer in 2026" advice circulating without a primary source behind it.
For context on the attention budget you are actually spending: Metricool's 2026 Instagram study (24.4M posts, 375K accounts) measures average watch time per Reel at 8.5 seconds — up 118% year over year, and still eight and a half seconds. Design the first eight accordingly.
Stories
For the audience you already have. Polls and question stickers are the one place a direct ask is not bait, because Stories are conversational by design. Use them to collect the exact words people use for their problem — that vocabulary is the raw material for every other channel in this pack.
Nothing durable lives in Stories. Do not put a claim there that is not also somewhere permanent.
What not to do
- Engagement bait. "Which one are you", "comment below", "tag a friend". Suppressed, and it makes the comment section worse.
- Cross-posting the TikTok file with the TikTok caption. The watermark alone is enough to suppress it; the caption mismatch does the rest.
- Text-heavy cards. If a card needs more than a title and a line, it is two cards.
- A carousel where card 4 is an illustration of proof rather than proof.
- Skipping alt text. It is the only machine-readable layer the post has.
- Inconsistent signature. If Instagram is signed by "the team" and another channel by one person, someone following both notices.
Related skills
- tiktok-script — the same idea, authored for a cold scroll instead of a feed.
- youtube-shorts — the same idea, authored for a search query.
- claim-check — run on caption, card text, and alt text together.
- social (upstream) — any other platform, and cross-platform posting plans. The link mechanics, aspect ratios and hashtag guidance here are Instagram-only; LinkedIn, Facebook and X all have clickable in-post links.
- image (upstream) — generating and optimising the card assets themselves.
