Asking the AI to "improve my prompt" and using a prompt checker sound like the same thing, but they fix different problems. The rewrite polishes what you already wrote. The checker tells you what you left out before it costs you an answer. If you’ve tried the first and been unimpressed, the second is probably what you actually wanted.
What "improve my prompt" actually does
When you ask a model to rewrite your prompt, it works only with the words already on screen. It can make them smoother, longer, more formal. What it can’t do is add the context it never had — your real audience, the constraint you didn’t mention, the format you actually need. It frequently returns something that reads more confident without being more specific.
It also costs a round-trip. You type, wait for the rewrite, read it, then send the rewrite and wait again. For a quick task that’s two extra waits to fix a prompt you could have fixed in one line.
What a prompt checker does differently
A prompt checker reads your draft before you send and points at the gaps — no output format, no audience, a request buried under setup, sensitive data you probably didn’t mean to paste. It’s a diff against a good prompt, not a rewrite of a vague one. You stay the author; it just makes the missing pieces visible while they’re still cheap to add.
The distinction that matters: a rewrite optimizes wording, a checker surfaces omissions. Most weak prompts fail on omissions, which is why polishing them rarely helps much.
| Ask the AI to rewrite | Prompt checker (e.g. BeforePrompt) | |
|---|---|---|
| When it runs | After you send | Before you send, as you type |
| What it can use | Only the words you typed | Your draft + what a strong prompt needs |
| Main effect | Smoother wording | Fewer missing pieces |
| Round-trips added | One (or more) | None |
| Catches pasted secrets | No | Yes, locally in the browser |
Where the checker approach falls short (honestly)
A checker won’t write the prompt for you. It tells you the format is missing; you still decide what format you want. It flags that context is thin; it can’t invent the context only you know. If you want the machine to do the thinking, the rewrite is closer to that — it just tends to produce confident mush.
And a local checker is a habit tool. It works because it nudges you at the right moment, every time. If you ignore the nudge, it does nothing — same as a spell-checker you never look at.
Which should you use?
If your prompts come back smooth but generic, you don’t have a wording problem — you have an omissions problem, and a pre-send check helps more than a rewrite. If you genuinely want the model to draft the instruction from a rough idea, the rewrite is fine; just expect to add the specifics yourself afterward.
BeforePrompt is the checker version, built for people who already know how to prompt and just skip the parts under time pressure. It runs locally in the browser, so the check itself never sends your draft anywhere — your text only leaves your machine if you deliberately click a cloud rewrite. That’s the honest trade: it won’t think for you, but it’ll stop you shipping the vague first draft.