diff --git a/README.md b/README.md
index 9b589c0..a1034d7 100644
--- a/README.md
+++ b/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
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 0000000..5500f00
--- /dev/null
+++ b/requirements.txt
@@ -0,0 +1 @@
+PyYAML