Where: the sparkles icon (AI captions) in the corner of a caption box in the post editor.
How it works#
AI captions is the AI for writing, built into the post editor. Tell it what the post is about and it writes a caption in the tone, length and language you choose, with hashtags if you want them. Or let it rework what you've written: rephrase it, shorten it, make it punchier or fix the spelling and grammar. You read the result, then press Apply to put it in your post.
It's unlimited on the plans sold today and it doesn't use AI actions. It's separate from Hero_Agent, which plans and saves whole posts for you: Hero_Agent and your connected AI tools run on monthly credits instead, because every task uses AI that costs money each time. See AI actions.
Write a new caption#
- In the post editor, click the sparkles icon (AI captions) in the corner of the caption box. With an empty box, it opens on New Caption.
- Optional: pick a network under Templates, then click a ready-made prompt to copy it into Prompt. Replace the placeholder, such as {{ topic }}, with your subject.
- Write or finish the Prompt, for example "Announce our autumn sale: 20% off all candles until Sunday, free shipping over $50".
- Choose Tone, Creativity, Words, Hashtags and Language if you like (table below).
- Press Generate. The caption types itself in on the View/Edit tab.
- Edit it in the box, or use the rewrite buttons.
- Press Apply. The caption replaces what was in the box.
| Option | Choices | What it changes |
|---|---|---|
| Templates | Facebook, Instagram, LinkedIn, Google Business, X, Pinterest, YouTube, TikTok | Ready-made prompts for that network |
| Tone | Polite, Witty, Enthusiastic, Informational, Funny, Formal, Informal, Humorous, Serious, Optimistic, Motivating, Respectful, Assertive, Conversational, Casual, Professional, Smart, Nostalgic, Straightforward, Confident, Friendly | How it sounds |
| Creativity | Economic, Average, Good, Premium | From the most predictable wording to the most creative |
| Words | 25, 50, 100, 150, 200, 250, 500 | About how long it is |
| Hashtags | 1, 2, 3, 5, 10, 15, 20, 30 | How many hashtags it adds |
| Language | 84 languages | The language it writes in |
Every option can stay blank. If your browser is set to one of 15 widely used languages, Language starts on it; otherwise it starts on English. Left blank, it writes in the language of your prompt.
Rewrite what you have#
- Click AI captions in a box that already has text. It opens on View/Edit.
- Press Rephrase, Make shorter, Make punchier or Fix spelling and grammar. To rewrite into another language, pick it under Language first.
- Each result is kept as a numbered version. Click the numbers to compare them.
- Press Apply to use the version on screen, or Cancel to keep your original.
You can edit the text in the box before pressing a rewrite button: the rewrite starts from your edited text. Tone, Creativity, Words and Hashtags apply to new captions only.
Where you'll find it#
| Place | Fields |
|---|---|
| Post editor, All tab and network tabs | Caption, First Comment, YouTube Description, TikTok Title, Reddit Text |
| Automations | The Custom Caption field, when an automation's caption is set to Custom |
| Caption Library | The caption box when you create or edit a saved caption |
It isn't on the YouTube and Pinterest Title boxes, the Reddit Caption box, or link fields.
Tips#
- Check the length. AI captions doesn't keep to each network's character limit. Watch the character counter (for example 120/2,200 on Instagram) and use Make shorter if you're over.
- Put the facts in the prompt. AI captions writes from your prompt and the options you choose. It doesn't read your brand voice or the facts Hero_Agent has saved, so include prices, dates and links yourself.
- Apply replaces the whole box. To keep part of your text, edit the result before you apply it.
- Nothing is posted. Apply only fills in the field. You still schedule or publish the post as usual.
Limits#
| Plan | AI captions a month |
|---|---|
| Plans sold today (Growth, Pro, Agency), scheduler plans, Lifetime Starter, Growth and Agency, and the free trial | Unlimited |
| Some older lifetime deals | 3 |
- Each press of Generate or a rewrite button counts as one.
- AI captions are counted for each person, per calendar month (UTC).
- They never use Hero_Agent's actions or Hero_Photo's credits.
On heropost.ai/pricing, every plan includes "Unlimited AI captions & hashtags".
On a phone#
The AI captions window fills the screen on phones and small tablets. On very narrow screens the Templates panel is hidden: write your own prompt instead.
If it doesn't work#
| What you see | What it means | What to do |
|---|---|---|
| "Something went wrong" | The caption couldn't be written this time. | Press Generate again. If it keeps happening, contact support with the time and what you typed. |
| Time to Level up! with "Upgrade to get unlimited access and unlock more features." | Your older lifetime deal includes 3 AI captions a month, and they're used. | Press Upgrade to see the plans, or wait for the 1st of next month. |
| Generate stays gray | The Prompt is empty. | Type a prompt or pick a template. |
| Apply stays gray | It's still writing, you're on the New tab, or the box is empty. | Wait for the text to finish, then apply it from View/Edit. |
| The caption is too long for the network | The AI doesn't count characters for you. | Press Make shorter, then check the counter. |
| No sparkles icon on a field | That field doesn't have the AI writing tools. | Write it by hand, or use AI captions on the caption box and copy the text. |
Questions#
Does AI captions use my AI actions?
No. It's the AI for writing included in your plan. Actions are only for Hero_Agent and connected AI tools.
Which languages can it write in?
84, chosen under Language. It can also rewrite a caption into another language from the View/Edit tab.
Can my connected AI tool use AI captions?
No. AI captions works in the Heropost app. ChatGPT, Claude and other connected tools write the copy themselves, then save it to Heropost.
Does it know my brand?
Not automatically: it writes from your prompt and options. For posts written from your brand voice and saved facts, ask Hero_Agent, or put the key points in your prompt.
Can I get my original caption back after applying?
Cancel before applying keeps your original. After Apply, the field holds the new text; open AI captions again and you'll start from that text.