Update cli-usage.md

Author: AndrewClements84

docs/cli-usage.md

@@ -28,6 +28,18 @@ Validate a prompt for completeness and token safety.
 promptstream validate --template "./examples/summary.txt" --var topic=AI
 ```
 
+---
+
+## 📊 Analyze
+
+The **`analyze`** command estimates token usage and cost for a given prompt.
+
+```bash
+promptstream analyze --template "<path or text>" [--var key=value ...] [--model <modelId>] [--output json|table]
+```
+
+---
+
 Outputs:
 ```
 ✅ Valid prompt (37 tokens)