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character-prompt-fortifier-for-gemini3

character-prompt-fortifier-for-gemini3 is a skill for Claude Code from gpsnmeajp/ai-character-checker. It costs 51 tokens per session (8,934 once invoked), scanned A, original, CC0-1.0.

A prompt-writing skill for making AI characters more consistent when used with Gemini 3, Google's reasoning-focused AI model. It rebuilds character prompts using twelve techniques plus adjustments for Gemini 3.

In plain words
What is it for?
Use it to rewrite AI character prompts specifically for Gemini 3. It is intended for Gemini 3 versions 3.0 and 3.1, not as a general cross-model solution.
Why use it?
It addresses problems such as the character changing behavior across turns, confidently inventing information, or ignoring fictional settings that conflict with real-world knowledge.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the ai-character-checker plugin — 20 skills shipped together

not rated 6repo 7mo ago A scan 51 tokens original CC0-1.0

Good fit Use it to rewrite AI character prompts specifically for Gemini 3. It is intended for Gemini 3 versions 3.0 and 3.1, not as a general cross-model solution.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/gpsnmeajp/ai-character-checker/character-prompt-fortifier-for-gemini3
View source ↗ gpsnmeajp/ai-character-checker
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 gpsnmeajp/ai-character-checker --skill character-prompt-fortifier-for-gemini3
Clone the repo
git clone --depth 1 https://github.com/gpsnmeajp/ai-character-checker

Made for: Claude Code.

Or install ai-character-checker, the plugin that ships this one along with the rest of its 20 skills.

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 character-prompt-fortifier-for-gemini3

README.md
[![agentmods](https://agentmods.dev/badge/skills/gpsnmeajp/ai-character-checker/character-prompt-fortifier-for-gemini3/github.svg)](https://agentmods.dev/skills/gpsnmeajp/ai-character-checker/character-prompt-fortifier-for-gemini3)
Your own site
<a href="https://agentmods.dev/skills/gpsnmeajp/ai-character-checker/character-prompt-fortifier-for-gemini3"><img src="https://agentmods.dev/badge/skills/gpsnmeajp/ai-character-checker/character-prompt-fortifier-for-gemini3/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.

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Your own site · 80×15
<a href="https://agentmods.dev/skills/gpsnmeajp/ai-character-checker/character-prompt-fortifier-for-gemini3"><img src="https://agentmods.dev/badge/skills/gpsnmeajp/ai-character-checker/character-prompt-fortifier-for-gemini3.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 51 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 8,934 The whole file, excluding the scripts and references it only reads on demand.
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 $0.00051 $0.08934
Opus 5.5 $0.00020 $0.03574
Sonnet 5.5 $0.00010 $0.01787
Haiku 4.5 $0.00005 $0.00893

Measured 2mo ago against content hash 7d95e37f1e7d, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

character-prompt-fortifier-for-gemini3 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 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.

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.

skills/character-prompt-fortifier-for-gemini3/SKILL.md · 484 lines

How it starts

The opening of the file, as written. The whole thing — 484 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Character Prompt Fortifier for Gemini 3

— AIキャラクタープロンプト Gemini 3向け崩壊耐性強化スキル

概要

このスキルは、AIキャラクタープロンプトを 12の強化技法 + Gemini 3固有の最適化 で再構成し、 Gemini 3（3.0/3.1）で最高の安定性と性能 を引き出すプロンプトに変換する。

character-prompt-fortifier との関係

本スキルは character-prompt-fortifier の Gemini 3特化版 である。 12の強化技法（一人称自述形式、制約の内在化、理由付け等）の理論的基盤は共通だが、 Gemini 3の特性に合わせた適応を全面的に組み込んでいる。

項目 character-prompt-fortifier 本スキル
対象モデル SLMから推論モデルまで汎用 Gemini 3（3.0/3.1）専用
技法 12技法 12技法 + Gemini 3適応レイヤー
追従性対策 技法10で基本対策 Gemini 3の強い追従性に対する重点強化
幻覚対策 限界分離で間接対処 明示的な「不明」脱出路 + Split-Step設計
反事実的前提 汎用的な存在論的分離 「設定を絶対的ルールとして扱え」の強い宣言
構造 XML+Markdown 同一（ただしフォーマット混在を厳格に禁止）
パラメータ 汎用推奨 temperature=1.0、thinking level推奨

汎用的なクロスモデル耐性が必要な場合は、元の character-prompt-fortifier を使用すること。

なぜGemini 3専用版が必要か

Gemini 3は「reasoning model」として設計されており、以下の特性が汎用版とは異なる対応を要求する:

  1. 追従性が極めて強い — ユーザーの期待に合わせて意見を曲げ、マルチターンで急速にエスカレート。技法10を大幅強化する必要がある
  2. 幻覚を自信満々に生成する — 「知らない」と言うのを避ける傾向。「わからないことはわからないと言う」を信念に組み込む必要がある
  3. 反事実的前提を維持できない — 訓練データの世界知識に固執し、設定と現実が矛盾すると設定を無視。存在論的分離で強い宣言が必要
  4. 過度に複雑なプロンプトを過剰分析する — 装飾的文言を深読みし意図しない解釈をする。自述は直接的・簡潔に
  5. 手動CoTが逆効果 — reasoning modelなので「ステップバイステップで」は冗長。thinking levelに委ねる

既存スキルとの関係

スキル アプローチ 本スキルとの関係
character-prompt-fortifier 汎用クロスモデル強化（12技法） 本スキルの基盤。Gemini 3固有の適応を追加した特化版
gemini3-prompt-optimizer 汎用プロンプトのGemini 3最適化 Gemini 3の特性知識・アンチパターン知識の源泉。本スキルはその知見をキャラクター強化に統合
ai-character-fixer 診断結果に基づく個別修正 内容修正（fixer）と形式変換（本スキル）は相互補完
ai-fault-mode-deflector 故障モード内部対策設計 3手法（転化・ズラし・誘導線）を一人称自述形式に自然統合
ai-character-stability 制御工学的安定性診断 強化前後のSM値を比較すると効果を定量確認できる
ai-character-6-type-checker 6軸統合簡易診断 強化後に自動実行（Phase 6）し改善を定量確認
romantization-chain-detector 連鎖型故障モード脆弱性検出 12技法で6種のチェーンへの構造的耐性を間接的に組み込む

理論的位置づけに関する注意

本スキルが前提とする診断理論・強化技法体系は作者独自の仮説的モデルであり、学術的に実証されたものではない。工学的用語は概念の借用であり、元の定義と異なる場合がある。出力結果はあくまで参考情報として扱うこと。この旨をユーザーへの出力に含めること。

Read the full file on GitHub · 484 lines

Files

What ships with it

3 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 · 484 lines · 51 tokens per session scan A 7d95e37f1e7d

Subscribe to this mod's changes

character-prompt-fortifier-for-gemini3 is a skill published in the GitHub repository gpsnmeajp/ai-character-checker (6 stars, last pushed 7mo ago), licensed CC0-1.0. It adds 51 tokens to every session and 8,934 once invoked, about $0.0002 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.

Data and AIPrompting
Related

character-prompt-fortifier-for-gemini3 compared with skills from other repositories

character-prompt-fortifier-for-gemini3 next to 6 skills from other repositories
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character-prompt-fortifier-for-gemini3gpsnmeajp/ai-character-checkerSkill67mo agoCC0-1.0A51Claude Code
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prompt-engineerJeffallan/claude-skillsSkill12k7d agoMITA93Claude Code
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