update readme and add requirements.txt

README.md

@@ -16,6 +16,18 @@ skills-claude/
         └── *.py / *.sh
 ```
 
+## Prerequisites
+
+- `unzip` — required by `decompress-skills.sh` to extract `.skill` archives
+  ```bash
+  sudo apt install unzip   # Debian/Ubuntu/WSL
+  brew install unzip       # macOS
+  ```
+- Python 3 + `PyYAML` — required by skill scripts
+  ```bash
+  pip install -r requirements.txt
+  ```
+
 ## How to install skills on Claude.ai
 
 ### 1. Generate .zip files

requirements.txt

@@ -0,0 +1 @@
+PyYAML