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🔧Prompt Improver

Most people type a prompt the way they would type a Google query: short, casual, and missing half the information the model needs to do the job. The result is generic output, hedged paragraphs, and three rounds of follow-up clarifications before anything useful appears. The FixTools AI Prompt. Improver fixes that gap. Paste your draft prompt and the tool rewrites it with the four ingredients that consistently produce better responses across ChatGPT, Claude, Gemini, Cursor, and every other current model: a clear role for the assistant to adopt, a concrete task with measurable scope, explicit constraints that rule out the common failure modes, and an exact output format so the response slots straight into your workflow. The free tier handles prompts up to 800 characters, which covers most everyday questions, while the paid tier extends to 6,000 characters for long system prompts, multi-step agent instructions, and detailed creative briefs. Nothing is stored after rewriting.

Adds role, task, constraints, and output format to any draft prompt
Free up to 800 characters, paid up to 6,000 for system prompts and agent instructions
Works for ChatGPT, Claude, Gemini, Cursor, Copilot, Midjourney, and. Stable. Diffusion
Returns the rewritten prompt only, with no commentary or filler to delete
0 chars

Anatomy of a weak prompt versus a sharp one

A weak prompt looks like this: "write me an email to my landlord about the broken heating." It is grammatically fine, the intent is obvious to a human reader, and it produces an answer in two seconds. The answer, however, is almost always disappointing. The model will write a polite, generic, four-paragraph email that sounds like every other complaint letter on the internet, opening with "I hope this email finds you well" and closing with "I look forward to your prompt response." It will guess that the heating has been broken for some unspecified time, invent a reasonable but fictional context, and produce something you then have to rewrite anyway. The reason is not that the model is bad at writing emails. The reason is that you have given it no information about your tone, your relationship with the landlord, how serious the situation is, what you have already tried, what outcome you want, or how long the message should be. The model is filling in those blanks with the statistical average of every landlord email in its training data, which is exactly the bland output you received.

A sharp version of the same prompt looks like this: "Act as a tenant who has been polite for six months but is now frustrated. Write a 120-word email to my landlord requesting an electrician this week for a heating system that has been broken since. November 14, with two children in the flat. Tone: firm but not aggressive. Cite the implied warranty of habitability in passing without sounding like a lawyer. No greeting like 'I hope this finds you well.' End with a specific deadline of Friday. Output only the email body and subject line." That is the same underlying request, restructured to give the model the four things it needs. Role: a tenant with a specific history. Task: a 120-word email with a clear ask. Constraints: tone, what to cite, what filler to avoid, and a deadline. Output format: subject line plus body, nothing else. The response from any frontier model on this rewritten prompt is dramatically better, usually usable with minor edits, and gets there in one shot rather than four.

The. Prompt. Improver makes that rewrite mechanical. Paste your weak draft, and the tool identifies which of the four ingredients are missing and adds reasonable defaults you can edit. If you wrote "summarise this article," the improver will ask for what length, what audience, and what tone, and produce a sharpened version such as "Summarise the article in 150 words for a non-technical reader. Lead with the single most surprising claim. Use plain. English, no jargon. Output as three short paragraphs with no headings, no bullet points, no preamble." If you wrote "give me a Python function to parse a CSV," it will rewrite to specify the input shape, expected output, error handling, library constraints, and whether you want type hints. The tool is opinionated about these defaults because empty defaults are the source of weak output. Every constraint added is a constraint the model no longer has to guess at, and guessing is where mediocrity comes from.

Two patterns are worth understanding because they appear in almost every weak prompt. The first is the implicit-audience problem: people forget to tell the model who the output is for, so the model writes for an imaginary general audience that nobody actually is. "Explain quantum entanglement" produces a Wikipedia-tier paragraph that is too dense for a child and too shallow for a physicist. "Explain quantum entanglement to a curious 12-year-old who has heard of atoms but not of wave functions, in three short paragraphs, with one analogy involving everyday objects" produces something genuinely useful for that specific reader. The second is the negative-constraint problem: people specify what they want but not what they want to avoid. Saying "write a product description for a coffee grinder" leaves the model free to produce the exact marketing cliches you hate. Adding "no words like 'elevate,' 'unleash,' 'seamless,' or 'game-changer,' and no rhetorical questions" closes off the failure modes that you would otherwise have to manually delete. Sharp prompts are not longer for the sake of being longer; they are longer because they have eliminated the ambiguities that make a model hedge.

How to use Prompt Improver

  1. 1

    Paste your draft prompt

    Open the Prompt. Improver and paste the prompt you were about to send to ChatGPT, Claude, Gemini, or another assistant. It does not need to be polished; the rougher the draft, the more the tool has to work with The free tier accepts up to 800 characters of input, which is enough for most everyday questions, requests, and short instructions. If your draft is longer, the paid tier lifts the ceiling to 6,000 characters for full system prompts, agent specifications, and long creative briefs.

  2. 2

    Pick the target model family

    Select whether the rewrite is intended for a chat model like ChatGPT or Claude, a coding model like. Cursor or. Copilot, or an image model like. Midjourney or. Stable. Diffusion. The four ingredients are the same across families, but the conventions differ. Chat models respond well to explicit role instructions and tone constraints. Coding models prefer input and output schemas with type information. Image models want comma-separated descriptors with weights rather than full sentences. The improver applies the right conventions automatically.

  3. 3

    Add any non-negotiable constraints

    Use the optional constraints field to lock in anything the rewrite must preserve. Common entries are word count limits, banned words or phrases, required citations, a specific persona, or an output format such as JSON or Markdown. The improver treats these as hard constraints and writes around them rather than overriding them. Leaving the field empty is fine; the tool will infer reasonable defaults from your draft.

  4. 4

    Run the rewrite

    Click. Improve. Prompt and wait two to five seconds for the rewritten version to appear. The output contains only the new prompt, with no preamble, no explanation, and no "here is your improved prompt" wrapper to delete. The tool is built this way so you can copy the result directly into your assistant of choice without manual cleanup. If you want to see what changed, toggle the diff view to highlight added constraints and reworded sections.

  5. 5

    Test it in your assistant

    Paste the rewritten prompt into ChatGPT, Claude, Gemini, Cursor, or wherever you originally planned to send it, and compare the response to what your original draft produced. In nearly every case the improved version returns output that is more specific, better formatted, and closer to what you actually wanted. If the response still misses, the diff view often reveals which constraint to tighten, and a second pass through the improver usually closes the gap.

Real-world use cases

First-time ChatGPT user who walked away disappointed

Someone who tried ChatGPT once during the hype cycle, asked it "write a blog post about productivity," and got back 800 words of cliches about morning routines and time-blocking. They concluded the tool was overrated and stopped using it. The. Prompt. Improver rewrites their draft into something like "Write an 800-word blog post for software engineers who already use time-blocking and are skeptical of productivity advice. Lead with a counterintuitive claim. Use one specific anecdote, no listicles, no headings, conversational tone, and avoid the words 'hack' and 'optimise'." The output from that prompt is the article they expected the first time, and they come back to AI tools with a different mental model.

Developer fighting with Cursor or Copilot suggestions

A backend engineer asks. Cursor to "add error handling to this function" and gets a wrapping try-except that swallows exceptions and prints them. The improver rewrites the request to "Add error handling that catches only requests.exceptions.RequestException and json.JSONDecodeError. Log the exception with logger.exception, re-raise as a custom. ServiceUnavailable error from the errors module, and do not catch generic. Exception. Preserve all existing type hints. Output only the modified function." The next suggestion respects the codebase conventions and lands in a single review pass rather than three.

Content creator improving Midjourney and Stable Diffusion prompts

A creator working on a series of illustrations keeps getting. Midjourney outputs that look like everyone else's. Midjourney outputs: hyper-saturated, symmetrical, with the same default depth-of-field. They paste "cyberpunk street market at night" into the improver and get back "cyberpunk street market at night, low-angle handheld camera, rain on wet asphalt reflecting magenta and teal neon, vendor stalls with mismatched tarpaulins, background extras in soft focus, shot on Kodak. Portra 800, slight film grain, asymmetric composition, no lens flare, no character in foreground, --ar 16:9 --stylize 250." The result is recognisably their style rather than the platform's default.

Marketer A/B testing prompt variants for ad copy

A growth marketer needs ten variants of a headline for a paid social test and wants each variant to explore a distinct emotional angle. They paste their base prompt into the improver, which rewrites it as "Generate ten headlines under 60 characters each for a B2B SaaS landing page selling expense management software. Each headline must use a different angle from this list: fear of audit, time savings, peer pressure, cost control, regulatory compliance, ease of switching, mobile convenience, finance team relief, CEO oversight, end-of-month panic. Output as a numbered list with the angle in parentheses after each headline." The variants are now testable as a clean factorial rather than ten variations on the same theme.

Pro tips

💡 Lead with the output format, not the topic

Models pay disproportionate attention to the first and last sentences of a prompt. Putting the output format up front ("Output a JSON object with fields title, summary, and tags") anchors the model on the shape of the response before it starts generating, which dramatically reduces the chance of wandering preamble. The improver always pulls format constraints to the start or the end for this reason.

💡 Use negative constraints aggressively

Telling the model what not to do is often more effective than telling it what to do. "No bullet points, no headings, no rhetorical questions, no closing summary" is more useful than "write in flowing prose." The improver builds a default negative-constraint list from the most common AI cliches, including the words "elevate," "unleash," "seamless," "delve," "tapestry," and the phrase "in today's fast-paced world."

💡 Give the model an out for uncertainty

Models hallucinate more when they are forced to produce a confident answer. Adding "If you are not sure about a specific fact, say so explicitly rather than guessing" measurably reduces fabrication in tasks involving citations, dates, and named entities. The improver adds this constraint by default to any prompt that asks for factual content.

💡 Re-run weak outputs through the improver as feedback

If a response still misses after one pass, paste both the prompt and the bad response back into the improver and describe what went wrong. The tool can read the failure mode and write a tighter prompt that closes the specific gap. This is faster than iterating in chat, where context accumulates and the model can drift further from the original intent.

Frequently asked questions

What does the prompt improver actually change?

It adds the parts a weak prompt is missing: a clear role for the AI, a specific task description, constraints on what to include or avoid, a defined output format, and tone. Vague prompts produce mediocre output because the model has to guess what you want. A sharpened prompt produces tighter, more usable results on the first try.

Will it preserve my original intent?

Yes. The rewriter keeps your goal intact and only adds structure around it. If you wanted a follow-up email, you get a prompt that produces a follow-up email. The improvements are about specificity and format, not about changing what you asked for.

Can I use the improved prompt with ChatGPT, Claude, or Gemini?

Yes. The output is platform-agnostic, structured prompts work well with any modern language model. The same prompt will produce similar quality output across Claude, GPT-4, Gemini, and Llama variants.

How long can my prompt be?

Free tier accepts inputs up to 800 characters, which covers most everyday prompts. With credits, the limit rises to 6,000 characters, enough for prompts that include extensive context or examples.

Is my pasted prompt stored or shared?

No. The prompt is sent to Anthropic Claude for the rewriting step only. We do not store it, do not log it, and do not use it for training. Each session is independent.

Can I iterate on the output?

Yes. Paste the improved prompt back into the input and run again to refine further. You can also edit by hand, the improver gives you a starting point, not a final answer.

What if I want a specific output format like JSON or markdown?

Add the format requirement to your input prompt, the improver will preserve and reinforce it. If you say you need JSON, the improved prompt will include explicit JSON formatting instructions.

Does it work for image-generation prompts (Midjourney, DALL-E)?

Yes, though the structure is different. For image prompts the improver adds subject, style, composition, lighting, and aspect ratio details, the elements that distinguish a sharp image prompt from a vague one.

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