fix: improve description

Author: nblog

skills/nano-banana-pro-openrouter/SKILL.md

@@ -1,6 +1,6 @@
 ---
 name: nano-banana-pro-openrouter
-description: 'Generate or edit images via OpenRouter with the Image model. Use for prompt-only image generation, image edits, and multi-image compositing; supports 1K/2K/4K output.'
+description: 'Generate or edit images via OpenRouter image generation models (default: google/gemini-3-pro-image-preview). Use for prompt-only image generation, image edits, and multi-image compositing; supports 1K/2K/4K output.'
 metadata:
   emoji: 🍌
   requires:
@@ -16,7 +16,7 @@ metadata:
 
 ## Overview
 
-Generate or edit images with OpenRouter using `google/gemini-3-pro-image-preview` as the default model. Support prompt-only generation, single-image edits, and multi-image composition.
+Generate or edit images with OpenRouter using `google/gemini-3-pro-image-preview` as the default model. It supports prompt-only generation, single-image edits, and multi-image composition.
 
 ### Prompt-only generation