Repeats are asked once
Use {brand} four times and the fill sheet shows one field for it. Your answer goes into all four places.
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PROMPT TEMPLATE VARIABLES
PromptVault
Prompt variables
A prompt with blanks in it stops being a one-off.
Wrap a word in curly braces and it becomes a slot. PromptVault asks for the slots when you copy, drops your answers in, and hands you the finished text — while the prompt you saved stays exactly as you wrote it.
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What a variable is doing in a prompt
Most of a good prompt does not change. The constraints, the output format, the tone instruction, the bit where you told it not to write an introduction — that is the part that took three attempts to get right, and it is the same every time you use it. What changes is one or two nouns. A variable is simply a way of marking which is which.
The alternative is one of two bad habits. Retyping the prompt from memory loses precisely the structure that made it work, because structure is the part you do not remember. Editing the saved copy in place is worse: last week's brief is gone the moment you overwrite it, and you find out when you need it back. Templating keeps the invariant fixed and lets the variable part be variable.
PromptVault marks a slot with curly braces and a name — {topic}, {audience}, {tone}. It never edits the saved prompt when you use it. Copying is a read; the filled text exists only on your clipboard.
ONE PROMPT, TWO STATES
Blog Post Outline, straight out of the built-in library
This one ships inside the app. Three blanks, one prompt, a different brief every time you reach for it.
Write a detailed blog post outline about {topic} for an audience of {audience}. Include an attention-grabbing intro, 5 main H2 sections with 2-3 H3 subsections each, key points to cover under each, and a conclusion with a clear call-to-action. Tone: {tone}.
- topic rescheduling a booking without losing the deposit
- audience small salon owners
- tone calm and practical
Write a detailed blog post outline about rescheduling a booking without losing the deposit for an audience of small salon owners. Include an attention-grabbing intro, 5 main H2 sections with 2-3 H3 subsections each, key points to cover under each, and a conclusion with a clear call-to-action. Tone: calm and practical.
Paste it wherever you were going to type it. PromptVault does not talk to any AI service, and is not connected to or endorsed by one.
What counts as a variable, exactly
The parser is deliberately narrow, which is what stops it eating braces you meant literally. A name may contain letters, digits, underscores, hyphens and spaces, and nothing else.
| Written in the prompt | Read as |
|---|---|
| {topic} | A variable named topic |
| {target audience} | A variable named target audience — spaces are fine |
| {tone_of_voice} | A variable named tone_of_voice |
| {step-by-step} | A variable named step-by-step |
| { topic } | A variable named topic — the spaces around it are trimmed |
| {} | Not a variable. Left in the text as written |
| {json.output} | Not a variable — the full stop is not an allowed character |
| {"role": "user"} | Not a variable. JSON in a prompt survives untouched |
Order follows the text
Fields appear in the order the names first show up in the prompt, so filling top to bottom reads the way the prompt reads.
An empty field stays visible
Skip one and the placeholder is copied through unchanged. You paste {tone} and notice, rather than pasting a sentence with a hole in it.
JSON survives
Braces with punctuation inside are not variables, so an example payload in a coding prompt is left alone.
What happens when you tap copy
- 1 The sheet opens, if there is anything to fill. A prompt with no blanks skips straight to the clipboard, and its button says Copy Prompt rather than Fill & Copy.
- 2 One field per blank, first one already focused. The keyboard's next key moves down the list and the last field's done key submits, so a three-blank prompt is three lines of typing without touching the screen again.
- 3 The preview rewrites as you type. The finished prompt sits underneath the fields and updates on every keystroke, so you read the sentence you are about to send before you send it.
- 4 Copy Filled Prompt puts it on the clipboard. The prompt's copy count goes up by one — the detail screen shows it, which over a few weeks tells you which of your prompts you actually use.
Nothing leaves the phone at any point in that sequence. There is no account, and the app has no connection to any assistant you might paste into.
Putting them into your own prompts
You can type the braces yourself, or use the Insert variable button under the body field in the editor. It asks for a name — the hint offers topic, audience, tone — and drops the braced name in at the cursor. Underneath the field, a panel counts the variables it can see and lists them as chips, which updates as you type, so a mistyped brace shows up immediately as a missing chip rather than a surprise on the fill sheet.
Naming them so they still make sense in a month
- Name the slot, not one example of it. {audience} ages well. {small salon owners} is last Tuesday's answer stuck in the template.
- One idea per blank. Two fields you can answer in four words each beat one field that needs a sentence.
- Reuse the same names across prompts. Once topic, audience and tone mean the same thing everywhere, filling anything in your collection becomes muscle memory.
- Stop at three or four. Past that the sheet turns into a form, and a form is the thing you were trying to avoid. Only one of the 55 bundled prompts goes to five.
How the bundled prompts use them
Every one of the 55 prompts that ships with the app has at least one blank — they were written as templates rather than as examples. Counted from the library file itself:
Blanks per prompt
Names that come up most
- topic 8
- language 7
- tone 5
- goal 5
- audience 4
- code 4
- duration 4
Number of the 55 bundled prompts that use each name. Language turns up second because the coding and translation prompts all ask which one.
Questions
What is a prompt variable?
A blank inside a saved prompt. Write a name in curly braces, like {topic}, and PromptVault treats it as something to be filled in later. The prompt itself stays as it was written; each copy is one filling of it.
What can a variable be called?
Letters, digits, underscores, hyphens and spaces. So {topic}, {target audience}, {tone_of_voice} and {step-by-step} all work. Anything containing other punctuation is not read as a variable and is left in the text exactly as you typed it.
What happens if the same variable appears twice?
You are asked for it once. The fill sheet lists each name a single time, in the order the names first appear, and the value you give is substituted at every occurrence.
What if I leave a field empty?
The placeholder is left in place. An unfilled {topic} arrives on the clipboard still reading {topic}, so a blank you skipped is visible in the pasted text rather than quietly missing from it.
Does PromptVault send the filled prompt anywhere?
No. It is not connected to any AI service and has no affiliation with one. The finished text goes to your clipboard and you paste it into whichever assistant you use.
Do the built-in prompts use variables?
All 55 of them do. Fifteen have one blank, thirteen have two, twenty-one have three, five have four and one has five. Save any of them and you can rename the blanks or add your own.
Write the prompt once, fill it forever
Fifty-five templated prompts are already in there. Save one, rename its blanks, and see how much of your typing was never the interesting part.