docs: add authentication requirements

Author: Jamkris

README.ko.md

@@ -15,15 +15,24 @@
 
 2분 안에 설정을 완료하세요:
 
-### 사전 요구 사항 (Prerequisites)
-
-최신 공식 Gemini CLI가 설치되어 있는지 확인하세요:
-
-```bash
 npm install -g @google/gemini-cli@latest
+
 # 또는
+
 npm update -g @google/gemini-cli
-```
+
+````
+
+### 인증 설정 (필수)
+
+Gemini CLI를 사용하려면 API 키가 필요합니다.
+
+1.  [Google AI Studio](https://aistudio.google.com/)에서 API 키를 발급받으세요.
+2.  환경 변수로 설정합니다:
+
+```bash
+export GEMINI_API_KEY="여기에_API_키를_입력하세요"
+````
 
 ### 옵션 1: Gemini CLI를 통한 설치 (권장)
 

README.md

@@ -15,12 +15,25 @@ This extension provides production-ready agents, skills, hooks, commands, rules,
 
 Get up and running in under 2 minutes:
 
-### Prerequisites
+npm install -g @google/gemini-cli@latest
+
+````
+
+### Authentication (Required)
+
+The Gemini CLI requires an API key to function.
 
-Ensure you have the latest official Gemini CLI installed:
+1.  Get your API key from [Google AI Studio](https://aistudio.google.com/).
+2.  Set it as an environment variable:
 
 ```bash
-npm install -g @google/gemini-cli@latest
+export GEMINI_API_KEY="your_api_key_here"
+````
+
+Or configure it using the CLI (if supported by your version):
+
+```bash
+gemini config set apiKey "your_api_key_here"
 ```
 
 ### Option 1: Install via Gemini CLI (Recommended)