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AI Prompt Library

Browse a curated catalog of prompt templates for writing, coding, marketing, and research. One click to copy.

Updated June 2026
25 prompts
Writing
Shorten without losing meaning
Rewrite the following text to be 30% shorter while keeping every concrete fact, number, and name. Remove adjectives, hedging, and repetition. Do not add new ideas. Return only the rewrite.

Text:
{paste here}
Writing
Expand a bullet into a paragraph
Turn this single bullet into one tight paragraph (3–5 sentences). Keep the voice matter-of-fact. No intro phrases like 'Here is…'

Bullet:
- {paste here}
Writing
Email: say no politely
Write a 4-sentence email declining the request below. Be warm, specific about why not, and offer one concrete alternative.

Situation:
{paste here}
Writing
Rewrite for clarity
Rewrite this paragraph so a smart reader outside the field can follow it. Define the first use of each specialized term in 5 words or fewer. Keep sentences short.

Text:
{paste here}
Writing
Blog post outline
Create an H1, three H2 sections, and 2-3 H3 bullets per section for a blog post about: {topic}. Audience: {reader}. Angle: {angle}. Each H3 should hint at a specific example, not a generic subheading.
Coding
Explain this diff
Explain this git diff. For each changed hunk: (1) what the change does in plain English, (2) why someone might make this change, (3) one thing that could go wrong.

```diff
{paste diff}
```
Coding
Unit test generator
Write unit tests (framework: {jest/vitest/pytest}) for the function below. Cover: happy path, empty input, boundary values, error conditions. Each test should have a descriptive name.

```
{paste function}
```
Coding
Error message → fix
Here is an error message and the smallest snippet of code where it happens. Explain the root cause in 2–3 sentences, then show the corrected snippet with only the needed changes.

Error:
{paste}

Code:
```
{paste}
```
Coding
Regex builder
Write a regex that matches {describe}. Include: (1) the regex itself, (2) a one-line explanation, (3) three matching examples and three non-matching examples.
Coding
Refactor for readability
Refactor this function for readability, not performance. Name things well, remove nested conditionals, and keep behavior identical. Output only the refactored code plus a 2-line summary of what changed.

```
{paste}
```
Marketing
Headlines, 10 variations
Write 10 headlines for: {product or article}. Mix these styles: direct benefit, curiosity gap, contrarian, numbered, how-to, and social proof. No clickbait. Each under 70 characters.
Marketing
Cold email (warm tone)
Write a 90-word cold email. Recipient: {role at company}. Hook: {their recent thing}. Offer: {what I bring}. Ask: one 15-minute call. No 'hope this finds you well'. First line must name something specific and true about them.
Marketing
Landing page hero
Write 3 hero-section variants for the landing page of {product}. Each variant: 1 headline (≤10 words), 1 subhead (≤25 words), 1 CTA button text (≤3 words). Avoid hype words.
Marketing
Social post from article
Turn this article into: (a) 1 LinkedIn post (~150 words, first-person, one concrete example), (b) 1 Twitter/X thread of 5–7 tweets. No emojis unless absolutely needed.

Article:
{paste}
Research
5-minute primer
I have 5 minutes to understand {topic}. Explain: (1) what problem this solves, (2) the main approaches and how they differ, (3) the sharpest open question. Assume I'm smart but have no background in this field.
Research
Compare X vs Y
Compare {X} and {Y} across: typical use cases, cost, learning curve, ceiling of capability, and one-thing-each-is-bad-at. Return a markdown table. No hedging — pick a clear winner per row when one exists.
Research
Steelman the opposing view
I believe: {my position}. Steelman the strongest counter-position. Present 3 arguments a thoughtful critic would make, and for each: one piece of evidence and one concession I should make if I still disagree.
Career
Resume bullet rewrite
Rewrite this resume bullet using the format 'Action verb + what + measurable impact'. Remove buzzwords. Keep under 20 words.

Bullet:
{paste}
Career
Interview answer scaffold
I'm prepping for the question: '{question}'. Draft a 90-second STAR-format answer based on this situation: {context}. End with the lesson learned in one sentence.
Career
Salary negotiation script
Write a negotiation response. Offer I got: {offer}. My target: {target}. My leverage: {reason}. Keep it warm, firm, and under 100 words. End with a clear ask, not a question.
Learning
Explain it like I'm 12
Explain {concept} as if I'm 12. One analogy, one real-world example, and one common misconception — in that order. Max 150 words.
Learning
Flashcards from notes
Turn the notes below into 10 Anki-style Q/A flashcards. Make each question specific enough that guessing is impossible. Front: question. Back: answer + one-line 'why it matters'.

Notes:
{paste}
Learning
Socratic tutor mode
Act as a Socratic tutor on {topic}. Don't explain directly — ask me questions one at a time to guide me toward understanding. Start with the most basic one. Wait for my answer before moving on.
Meetings
Meeting notes → action items
From these raw notes, extract: (1) decisions made, (2) action items in the format 'Owner — action — due date', (3) open questions with nobody assigned. Skip small talk.

Notes:
{paste}
Meetings
Agenda for a hard conversation
Help me build an agenda for a 20-minute conversation with {person}. The hard topic: {topic}. Give me: (1) opening line, (2) 3 questions to understand their side, (3) the one truth I need to say, (4) a good exit line.
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What it does

Browse a curated catalog of prompt templates for writing, coding, marketing, and research. One click to copy. Production AI usage typically costs 3-5x what initial estimates suggest because of output-token weighting and prompt-cache misses.

Token counting matters: input vs output tokens, system-prompt overhead, RAG context all affect bills. The gap between “rough estimate” and “defensible number” is exactly where good tooling earns its keep — the math is reproducible, but knowing which inputs matter and what the result means is half the work.

Prompt caching (OpenAI: 50% off cached tokens; Anthropic: 90% off) is the single biggest cost optimization for chatty workloads. A common pitfall: treating model output as authoritative without verification. Treat the tool’s output as a starting point and validate against authoritative sources for any consequential decision.

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How to use it

  1. Open the tool and review the interface.
  2. Enter or paste your input.
  3. Configure any relevant options.
  4. Run the tool and review the output.
  5. Iterate or refine based on the result.

When to use this tool

  • Comparing API costs vs self-hosting for high-volume workloads.
  • Production cost forecasting based on traffic projections.
  • Prompt-engineering optimization to reduce token consumption.
  • Vendor selection between OpenAI, Anthropic, Google, and open-source.

When not to use it

  • When the workload is unique enough that public benchmarks don&rsquo;t apply.
  • For non-frontier image, video, or audio model pricing (those use per-asset billing).
  • When you have negotiated enterprise pricing not reflected in public rate cards.
  • For hyper-bursty traffic where peak load determines architecture, not average.

Common use cases

  • A ML engineers optimizing inference costs working through ai prompt library for a real decision.
  • A developers building LLM features working through ai prompt library for a real decision.
  • A researchers comparing model quality working through ai prompt library for a real decision.
  • A enterprise teams managing AI budgets working through ai prompt library for a real decision.

Frequently asked questions

How does this compare to GPT-4o or Claude Opus 4?
GPT-4o, Claude Opus 4, and Gemini 2.5 Pro are roughly comparable on quality for general tasks; their pricing differs by 30-50% so test on your specific workload before locking in.
What hidden costs am I missing?
Output tokens (3-5x input cost), rate-limit retry overhead (20-40% extra), failed-request charges, and the engineering time to maintain the integration. Budget 1.5-2x the headline rate.
How does self-hosting change the math?
Self-hosting Llama 3.3 70B on AWS p4d ($32/hr) costs ~$16/M tokens at full utilization. DeepSeek V3 API is $0.30/M tokens. Self-hosting wins only at 1B+ tokens/month consistent.
Should I switch to a smaller model?
Probably yes, after testing. Mini / Haiku tier handles 60-70% of production tasks adequately at 5-10x lower cost. Test on your specific workload, then route only failures to the larger model.
What about prompt caching and batch discounts?
Prompt caching saves 50-90% on cached input tokens (OpenAI: 50%; Anthropic: up to 90% with 5-minute cache). Batch API: 50% off async jobs. Combined, can drop bills 70-80% for cache-friendly workloads.
Is this calculation accurate at scale?
Public-rate-card calculators are accurate within 10-15% for typical workloads. Variance comes from prompt-cache hit rates, batch-API usage, and rate-limit retry overhead.

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