Chapter 13: Building a Prompt Library: Governance + Quality Bar

Series: LLM Development Guide

Chapter 13 of 15

Previous: Chapter 12: Templates + Checklists: The Copy/Paste Kit

Next: Chapter 14: Worked Example: Creating a Helm Chart From a Reference Chart

What you’ll be able to do

You’ll be able to build a prompt library that doesn’t turn into a junk drawer:

• Organize prompts by task type.
• Define a consistent prompt entry format.
• Set a contribution and maintenance policy.

TL;DR

• A prompt library is a shared collection of prompts proven in real usage.
• Require prereqs, recommended model tier, expected output, and common failure fixes.
• Assign maintainers.
• Version prompts with a changelog.

Table of contents

• Library structure
• Prompt entry template
• Contribution guidelines
• Governance
• Verification

Library structure

A simple layout that scales:

prompt-library/
  README.md
  CONTRIBUTING.md
  planning/
  implementation/
  testing/
  review/
  debugging/

Keep it boring. Avoid inventing new categories every week.

Prompt entry template

Require a consistent format so prompts are reusable:

# <Task Name>

## When to use

## Prerequisites
- 

## Recommended model tier

## The prompt

## Customization points

## Expected output

## Common issues and fixes

## Examples

## Changelog
- YYYY-MM-DD: <what changed>

Contribution guidelines

Set a quality bar:

• A prompt must have been used successfully multiple times.
• It must specify required reference files.
• It must include verification.
• It must include common failure modes and fixes.

A contribution checklist:

• Used successfully 3+ times.
• Another person can run it with the listed prereqs.
• Changelog updated.

Governance

If nobody owns it, it rots.

Assign 1 to 2 maintainers to:

• Review new prompts.
• De-duplicate similar prompts.
• Archive prompts that no longer work.
• Run a quarterly cleanup.

Verification

Bootstrap the skeleton:

mkdir -p prompt-library/{planning,implementation,testing,review,debugging}

touch prompt-library/README.md

touch prompt-library/CONTRIBUTING.md

cat > prompt-library/planning/new-task.md <<'MD'
# New Task Planning

## When to use

## Prerequisites

## Recommended model tier

## The prompt

## Verification
MD

Expected result:

• You have a real place to put prompts that worked, with enough structure to keep it maintainable.

Continue -> Chapter 14: Worked Example: Creating a Helm Chart From a Reference Chart