> ## Documentation Index
> Fetch the complete documentation index at: https://promostar.app/help/llms.txt
> Use this file to discover all available pages before exploring further.

# How to use PromoStar to check that a post fits a subreddit

> The Promo Planner composer shows what's working in a subreddit: Insights, rule highlights, flair choices, and Safety Lens badges when you pick media.

Open the composer for a subreddit and read **Insights**, the title hints, the flair choices, and the badges on your media. They show how the sub tends to run before you write.

## Steps

1. Open the composer for a sub from **Promo Planner**. The sub name shows at the top, as **r/** and the name.
2. Under **Post type**, pick **Media**, **Text**, or **Link**. The type changes the field you fill in: **Pick media**, **Write your post…**, or **Link URL**.
3. For media, click **Pick media**. The picker opens with a line that says which format leads in the sub's recent top posts. Each file can carry a badge:
   * **Posted here recently**: you marked this file posted to this sub in the last 30 days.
   * **Different format**: the sub's top posts mostly use another format.
   * **Safety Lens**: the sub reads as SFW and the file is marked NSFW.
   * **Not scored**: Safety Lens has not scanned the file.
4. Check **Title**. The line under it gives the typical title length and common tags. Open **This week** for recent top titles. A **Primarily bait titles** chip means most recent top titles there lean on bait hooks.
5. Check **Flair (optional)**. When the sub's flair list is available you get a dropdown. Otherwise you get chips from recent posts and a box to type your own.
6. Read **Insights**. The observations are marked **AI-assisted observations**. Rule lines sit under **Automated highlights**, and **Checked** shows the date PromoStar last read the rules. Click **View full rules on Reddit** to read the sub's own rules.

<Info>
  Insights read the sub's public rules and recent top posts. They do not check your title or your post against the rules, and they miss unwritten norms. The four badges above are advice, and you can still pick the file.
</Info>

## Good to know

* A sub with too few recent posts shows a note instead of observations. A sub with no rules on hand shows that rule highlights are not available yet.
* Flair choices from recent posts may be incomplete. Choose the matching flair on Reddit.

## Where processing happens

PromoStar's server fetches each sub's public rules and recent posts from Reddit. The PromoStar app writes the observations with a language model reached through OpenRouter, a third-party service. The model receives only stats and titles from the sub's public posts. It never receives your media, your account, or your drafts. Rule highlights come from the sub's public rules. Safety Lens badges use scores PromoStar already stored.

## Related

* [Pick a subreddit and a time](/help/promo-planner/pick-a-subreddit-and-a-time)
* [Read a Safety Lens score](/help/media-library/safety-lens)


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