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prompt-engineering

prompt-engineering is a skill for Claude Code, Codex from jshearin01/agent-skills. It costs 139 tokens per session (1,988 once invoked), scanned A, original, no licence file.

A guide for writing and improving instructions for language models such as GPT, Claude, Gemini, or Llama. It covers creating, refining, checking, shortening, and optimizing prompts.

In plain words
What is it for?
Writing new prompts, improving existing ones, auditing prompt quality, and adapting instructions for different language models.
Why use it?
It helps make model instructions clearer and more reliable. It can also reduce unnecessary wording while preserving the intended result.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

not rated 17repo 5mo ago A scan 139 tokens no licence

Good fit Writing new prompts, improving existing ones, auditing prompt quality, and adapting instructions for different language models.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/jshearin01/agent-skills/prompt-engineering
View source ↗ jshearin01/agent-skills
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add jshearin01/agent-skills --skill prompt-engineering
Clone the repo
git clone --depth 1 https://github.com/jshearin01/agent-skills

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for prompt-engineering

README.md
[![agentmods](https://agentmods.dev/badge/skills/jshearin01/agent-skills/prompt-engineering/github.svg)](https://agentmods.dev/skills/jshearin01/agent-skills/prompt-engineering)
Your own site
<a href="https://agentmods.dev/skills/jshearin01/agent-skills/prompt-engineering"><img src="https://agentmods.dev/badge/skills/jshearin01/agent-skills/prompt-engineering/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for prompt-engineering

Your own site · 80×15
<a href="https://agentmods.dev/skills/jshearin01/agent-skills/prompt-engineering"><img src="https://agentmods.dev/badge/skills/jshearin01/agent-skills/prompt-engineering.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 139 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,988 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00139 $0.01988
Opus 5.5 $0.00056 $0.00795
Sonnet 5.5 $0.00028 $0.00398
Haiku 4.5 $0.00014 $0.00199

Measured 2mo ago against content hash 946d13eea7f7, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

prompt-engineering scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Asks the agent to reveal its instructionslowSystem prompt leakage

Directions to print, repeat or translate the system prompt extract configuration the operator did not intend to expose.

### Extraction / Structured Output Prompt

Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.

prompt-engineering/SKILL.md · 210 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2mo ago First seen · 210 lines · 139 tokens per session scan A 946d13eea7f7

Subscribe to this mod's changes

prompt-engineering is a skill published in the GitHub repository jshearin01/agent-skills (17 stars, last pushed 5mo ago), with no licence file. It adds 139 tokens to every session and 1,988 once invoked, about $0.0006 per session on Opus 5.5. A static security scan graded it A with 1 finding (asks the agent to reveal its instructions). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Data and AIPrompting
Related

prompt-engineering compared with skills from other repositories

prompt-engineering next to 6 skills from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
prompt-engineeringjshearin01/agent-skillsSkill175mo agononeA139Claude Code, Codex
llm-app-patternsdavila7/claude-code-templatesSkill33kyesterdayMITA54Claude Code, Codex
prompt-engineerJeffallan/claude-skillsSkill12k7d agoMITA93Claude Code
prompt-optimizationlangwatch/langwatchSkill5.0kyesterdayApache-2.0A105Claude Code, Codex
omh-model-optimizationrlaope/oh-my-hermesSkill5.2kyesterdayMITA84Claude Code, Codex
ideogram4digitalsamba/claude-code-video-toolkitSkill2.5kyesterdayMITA99Claude Code
prompt-library-for-startupsaws/agent-toolkit-for-awsSkill3.4kyesterdayApache-2.0A228Claude Code