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Prompt Template Builder

Prompt Template Builder

Write reusable prompts with {{variables}}, fill them in, and copy the compiled result — saved locally in your browser

    Template Editor

    Description: General code review · Model: claude-sonnet-5

    Try a sample:

    Template catalog

    Your library

    Versioned JSON

    Saved templates appear here and persist in your browser across visits.

    Hard-coding prompts into code or scattering them across notebooks makes them hard to reuse and version. The Prompt Template Builder is a lightweight, browser-based prompt manager: write a template once using {{variable}} placeholders, and the tool detects every variable and renders an input for each. Fill them in and the compiled prompt updates live — then copy it straight into Claude, ChatGPT or your application. Templates can carry optional YAML-like frontmatter (a description, which model they are tuned for) and your whole library is saved to your browser's local storage, so you can save, reload, duplicate and delete prompts without an account or a server. There is no model behind this tool and no API key is ever needed — it only compiles text. Pair it with the Context Assembler to drop a whole codebase into a template variable.

    Examples

    A parameterised code-review prompt

    Template:
Review the following {{language}} code against {{standard}} best practices.
Return issues grouped by severity.

Variables detected: language, standard

Compiled (language=Python, standard=PEP 8):
Review the following Python code against PEP 8 best practices.
Return issues grouped by severity.

    Every {{variable}} becomes an input; the compiled prompt fills them in live.

    Frontmatter for metadata

    ---
description: General code review
optimized_for: claude-sonnet-5
---
Review this {{language}} code…

    A leading --- block holds metadata (description, target model). The body below it is the template.

    Reuse across sessions

    💾 Library (saved in your browser)
  • code-review
  • explain-like-im-five
  • refactor-for-readability

    Saved templates persist across visits in local storage — no account, no server.

    About this tool

    Build reusable prompt templates with {{variables}}, auto-fill values and copy the compiled prompt. Save a local library. Free and client-side — no AI calls. Prompt Template Builder runs in the browser on DevTools. There is no signup, and your input stays on this device unless the tool explicitly performs a live network lookup.

    What this tool does not do

    • Prompt Template Builder is a free in-browser utility, not a hosted API. It does not keep server-side history and is not a substitute for production verification in your own stack.

    How do I use this tool?

    1. How do I use Prompt Template Builder?

      Open Prompt Template Builder, enter or paste your input, and copy the result. The page works without an account.

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