Building a Prompt Library

Learning objectives

• Distinguish a Skill from a plain saved prompt and identify which each task warrants.
• Catalog the core Reddit-marketing prompt types worth saving from Stage 4 onward.
• Version and store a prompt library alongside your Skills folder.
• Apply a graduation rule for promoting a saved prompt into a full Skill.
• Retire prompts a Skill has already superseded rather than letting duplicates accumulate.

Prerequisites: Lessons 6.2.1-6.2.2.

Core concepts

Not every reusable Claude task deserves a full Skill. A Skill costs you frontmatter discipline, a folder, testing for reliable triggering, and ongoing maintenance, worth it for a task you run daily, like intent scoring. A saved prompt with {{variables}}, stored in a plain prompts/ folder or directly in your Project, is enough for tasks you run weekly or less, where the overhead of a formal skill isn't earned yet. The prompt library is the lightweight rung directly below Skills in this stage's toolkit, not a competing system.

Look back at what Stage 4 already asked you to build: an intent-classifier prompt, a reply-ratio checker, and a DM-personalization prompt. Those are your prompt library's founding entries, not new work, the job in this lesson is centralizing them, versioning them, and pointing them at the shared reddit-context/ files from Lesson 6.2.2 instead of the ad hoc paste-in language they started as. Real marketer builds documented in MKT1's newsletter survey of Claude Code workflows confirm this is exactly how practitioners actually operate: a handful of well-tested prompts, reused constantly, refined slowly, long before any of them become a formal automation.

A workable graduation rule: if you find yourself running the same prompt, with only the pasted variable content changing, three or more times in a single week, it has earned Skill status, build the SKILL.md, retire the loose prompt, and update anything that referenced it. Digital Applied's synthesis of Skills-plus-MCP marketing automation documents this exact maturation curve (verify their specific speed-gain figures independently, since they are vendor-reported), and it maps cleanly onto this course's own progression: Lesson 6.1.2's few-shot intent prompt became Lesson 6.2.1's reddit-intent-scorer skill precisely because it crossed that three-times-a-week threshold.

prompts/
├── reddit-launch-post-drafter.md    # weekly or less, stays a prompt
├── weekly-digest-synthesizer.md     # once a week, stays a prompt
└── ARCHIVED-intent-classifier.md    # superseded by reddit-intent-scorer skill

Keep an ARCHIVED subfolder rather than deleting superseded prompts outright, they document your team's history of what worked, and occasionally a retired prompt's phrasing is worth reusing inside a new skill's instructions body.

Video lessons

Supporting reading

• anthropics/prompt-eng-interactive-tutorial (GitHub) (https://github.com/anthropics/prompt-eng-interactive-tutorial), revisit as the source material for any prompt library entry that needs sharpening.
• What 4 Gen Marketers Are Building with Claude Code, MKT1 Newsletter (https://newsletter.mkt1.co/p/real-marketers-claude-code-builds), evidence of what a real, working marketer's prompt-and-skill library actually contains.
• Claude Skills + MCP: Marketing Automation Guide 2025, Digital Applied (https://www.digitalapplied.com/blog/claude-skills-mcp-marketing-automation-guide), the prompt-to-skill graduation pattern this lesson's three-times-a-week rule is drawn from.

Exercise

Audit your Stage 4 Claude-workflow prompts. Move each into prompts/ with {{variables}} and a pointer to the relevant reddit-context/ file. Flag any that already meet the three-times-a-week graduation rule.

Assignment

Submit your prompt library folder listing plus a one-paragraph graduation decision: which prompt (if any) you are promoting to a Skill this week, and why it crossed the threshold.

Claude workflow

• Skill idea: a "library-auditor" skill that reads your prompts/ folder and weekly-digests/ usage log together and recommends graduations automatically.
• Automation: a monthly archive sweep that moves any prompt unused in 60 days into an ARCHIVED/ subfolder for review, never a silent delete.

Expected outcomes

• Centralized prompts/ folder with all Stage 4 workflow prompts migrated and versioned.
• At least one prompt correctly identified for graduation to Skill status, with reasoning.
• Can explain the Skill-vs-prompt cost/benefit distinction without notes.