AI & Prompts

Prompt Generator & Optimizer

Turn a rough idea into a structured system prompt.

System prompt
# Role
You are a senior technical writer.

# Objective
Your task is to turn release notes into a customer-facing changelog.

# Context
Audience is technical admins. Product is a developer tooling platform.

# Constraints
- Never invent features
- Keep each entry under 30 words
- Use the present tense
- Ask a clarifying question if a required input is missing.
- If you are uncertain, say so rather than guessing.

# Tone
Neutral and precise

# Output format
Respond in Markdown. Output only the result — no preamble, no explanation of your process.

The Prompt Pack — 20 Templates That Earn Their Tokens

20 production-tested system + user prompt pairs, bolt-on modifiers and an evaluation method.

One email, no spam, unsubscribe any time.

About this tool

Effective system prompts are structured, not clever. This builder assembles your idea into the sections that reliably improve model output: role, objective, context, explicit constraints, and a specified output format.

What makes a good system prompt

Give the model a specific role, one clear objective, the context it cannot infer, hard constraints stated positively, and an exact output format. Ambiguity is where hallucination enters.

Iterating on prompts

Change one variable at a time and test against a fixed set of inputs. Prompts that work on one model often need retuning on another, so version them alongside your code.

How to use Prompt Generator & Optimizer

  1. 1

    Open Prompt Generator & Optimizer

    Everything runs on this page — there is nothing to install and no account required to use the free features.

  2. 2

    Add your input

    Paste or enter your values in the panel above. The tool updates as you type, so you can iterate quickly.

  3. 3

    Review the output

    Check the result, copy it with one click, and adjust the options until it matches what your system expects.

  4. 4

    Take it further

    Use the ai & prompts tips below to make the result production-ready, then unlock the gated extras via the form above.

Best practices

  • Measure before you optimise — capture real token counts and latency from production traffic.
  • Version prompts like code, with a changelog and evaluation set behind each change.
  • Default to the smallest model that passes your eval, and escalate selectively.
  • Set hard spend limits at the provider before you scale traffic.

Why Prompt Generator & Optimizer matters

LLM cost and quality are decided by details most teams never measure: token volume, prompt structure and model choice.

Without a number in front of you, budgets get set by hope and margins disappear as usage grows.

Related free & paid tools

Tool nameTypeKey featuresLink
OpenAI Prompt Engineering guideFreeCanonical techniques with worked examplesVisit
LangSmithOfferPaidPrompt versioning, evals and regression testingVisit
PromptLayerOfferFreemiumPrompt registry with A/B testing and historyVisit
promptfooFreeOpen-source prompt evaluation in CIVisit

Links marked Offer may be partner links. They cost you nothing extra and never affect which tools we recommend.

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Frequently asked questions

References