An AI reply generator writes a draft reply to a post on X so that you do not start from an empty box. Some are Chrome extensions that add a button to each post. Some are websites where you paste the post. A few are bots that post on their own. They are not the same thing, and the differences matter more than the feature lists suggest.
This is a plain guide to how these tools work and what to look at before you put one in your browser.
How an AI reply generator works
The steps are the same in almost every tool:
- You point it at a post, usually by clicking a button the extension added to that post.
- The tool takes the text of the post, and sometimes a little context such as who wrote it.
- It sends that text to a large language model with instructions about tone, length and style.
- The model returns one or more drafts.
- The draft is shown to you, copied to your clipboard or typed into the reply box.
Everything that makes one tool better than another happens in step 3. The instructions decide whether you get "Great insight, thanks for sharing!" or a reply that picks up a real detail from the post and sounds like a person.
Assistants and bots are different things
It helps to sort these tools into two kinds.
An assistant drafts. You read the draft, change it and press Reply. Nothing goes out without you.
A bot posts. It decides what to answer and sends the reply itself, often to many posts, sometimes around the clock.
The first is a writing aid, in the same family as spell check and autocomplete. The second is automation of an account, which X has rules about and which readers dislike. If you care about your account and your name, you want an assistant. We go through the reasons in is it safe to use AI for replies on X.
Seven things to check before you install one
1. Does it ever post for you?
Look for a clear statement that it does not. The draft should wait in the reply box, or on your clipboard, until you act.
2. Does it want your own API key?
Some tools ask you to paste an OpenAI key. That means a second account to manage, a bill that depends on how much you click, and a secret stored in your browser. Tools that run the model on their own server need no key from you.
3. What can it read?
A reply tool needs to read the post you clicked. It does not need your direct messages, your followers or every site you visit. Check which sites the extension runs on and what its privacy policy says it reads. Our safety check for X extensions shows where to find this.
4. Can it learn your voice?
Generic drafts are the main complaint about these tools. Look for a place to describe how you write, a default tone and length, and control over emojis and hashtags. Without those, every draft will sound like the average of the internet.
5. Does it handle your language?
If you reply in more than one language, check that the tool can match the language of the post, not only write in English.
6. What does it cost, and what is a "credit"?
Pricing pages count different things. Find out what uses up your allowance. In some tools every new draft does. In others, one request returns several drafts and looking at the next one is free. That changes the real price a great deal.
7. Who makes it?
A named company, a privacy policy you can read, and a way to reach a person are the minimum. An extension with none of the three is asking for a lot of trust.
What AI is good at in replies, and what it is not
Language models are good at structure and speed. They will find an angle on a post in a second, keep it to two sentences and match a tone you name.
They are weak in three places:
- They do not know what you know. A model has not run your company or tried the thing the post describes. The most valuable replies come from experience, and that part you add.
- They drift to the middle. Left alone, a model writes safe, agreeable, slightly formal text. Good tools push against this, and a description of your voice pushes further.
- They can be wrong. If a draft states a fact, check it before your name goes on it.
The practical conclusion: use the draft for the first 80 percent, and spend your ten seconds on the part only you can supply.
How XAICG answers the seven questions
XAICG is our own tool, so read this as the maker's description.
- It never posts. Drafts are typed into X's reply box and wait there, and a copy-only mode keeps them off the page.
- It needs no API key. The writing happens on our server.
- It reads the one post you click. The server does not store that post or the draft.
- You describe a persona once, and set tone, length, language and emoji.
- It writes in English, in the post's own language, or in one of 17 others.
- It is free for 5 comments a day. One request returns several drafts, and stepping through them does not use another comment. Paid plans start at $0.99 a month.
- It is made by Unique Labs, with a privacy policy, a support page and a contact page.
Whichever tool you choose, apply the same test after a week: are your replies still ones you would have been happy to write yourself? If yes, the tool is doing its job.