prompt-engineering-skill: Instructions file for Gemini CLI

GEMINI.md

prompt-engineering-skill GEMINI.md is an instructions file for Gemini CLI from PhAlves23/prompt-engineering-skill. It costs 1,067 tokens per session, scanned A, original, MIT.

Instructions for a Gemini CLI extension that improves draft prompts for coding and other tasks. It rewrites the prompt for clarity and structure instead of carrying out the task described by the prompt.

In plain words
What is it for?
Reviewing and rewriting prompts, preserving variables, choosing an appropriate structure, and recording the important changes made.
Why use it?
They help turn vague or overloaded requests into instructions that an AI model can follow more consistently.

Instructions file for Gemini CLI

Written for Gemini CLI: the file is GEMINI.md. Also seen: mentions Gemini CLI.

This is PhAlves23/prompt-engineering-skill's own configuration. It tells Gemini CLI how to work on prompt-engineering-skill itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything prompt-engineering-skill configures →

Reuse

Borrowing it

Nothing to install: this file belongs to PhAlves23/prompt-engineering-skill. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/PhAlves23/prompt-engineering-skill/main/GEMINI.md
Clone the repo
git clone --depth 1 https://github.com/PhAlves23/prompt-engineering-skill

Made for: Gemini CLI.

Wrote this? Show the measurements

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Per session 1,067 This file is loaded in full into every session.
When invoked 1,067 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original 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 $0.01067 $0.01067
Opus 5.5 $0.00427 $0.00427
Sonnet 5.5 $0.00213 $0.00213
Haiku 4.5 $0.00107 $0.00107

Measured 1mo ago against content hash fb98370c7636, 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-skill GEMINI.md scanned grade A with 0 findings 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 1mo 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.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

GEMINI.md · 77 lines

How it starts

The opening of the file, as written. The whole thing — 77 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Prompt Engineering — Gemini context

Loaded by the Gemini CLI extension (see gemini-extension.json). To use it, ask: "improve this prompt", "optimize this prompt", or paste a draft and ask to make it better.

Prompt Engineering

Turn a raw draft into a production-grade prompt. Improve the prompt, don't run it — return a rewritten version + a short changelog. Only execute the task the prompt describes if the user explicitly asks.

Operating principle

  • Calibrate effort to complexity. Simple prompt → lean structural rewrite. Complex prompt (reasoning, classification, generation with criteria, agentic) → full structure. Don't over-engineer.
  • If the draft is already good, say so and do the minimum. Don't invent changes to justify a rewrite.
  • Default target model is Claude 4.x. If the user names another (GPT/o-series, Gemini), adjust accordingly (reasoning models do NOT want "think step by step").
  • Preserve every {{variable}} from the original. Convert negative instructions into positive ones. Add motivation to non-obvious instructions.

Workflow

  1. Diagnose — real intent, task type, target model, audience, output format, constraints, dynamic variables, draft weaknesses.
  2. Select techniques — only those that add value (see decision table).
  3. Rewrite in the canonical structure.
  4. Self-review — could a colleague with no context run this without doubt? Fix what fails.
  5. Deliver — optimized prompt + changelog.

Canonical structure (omit sections that don't add value)

  1. Role/persona — one line: who the model is + domain.
  2. Task + objective — what to produce + success criterion (outcome-oriented).
  3. Context + motivation — background + why it matters.
  4. Data/inputs — in XML tags. Long-context (20k+ tokens): long data at the TOP, question at the END (+up to 30% quality).
  5. Instructions — numbered when order matters, positive, explicit scope ("apply to ALL sections, not just the first").
  6. Reasoning — <thinking> block for analytical tasks; NOT for reasoning models.
  7. Examples (few-shot) — 3–5 diverse, in <example> tags. Strongest lever for format/tone.
  8. Output contract — exact format (JSON schema, XML, "result only, no preamble"). Say what to do, not what to avoid.

Read the full file on GitHub · 77 lines

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. 1mo ago First seen · 77 lines · 1,067 tokens per session scan A fb98370c7636

Subscribe to this mod's changes

prompt-engineering-skill GEMINI.md is an instructions file published in the GitHub repository PhAlves23/prompt-engineering-skill (12 stars, last pushed 4mo ago), licensed MIT. It adds 1,067 tokens to every session, about $0.0043 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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