diff --git a/skills/baoyu-comic/SKILL.md b/skills/baoyu-comic/SKILL.md
index 5b5ac27..e60681a 100644
--- a/skills/baoyu-comic/SKILL.md
+++ b/skills/baoyu-comic/SKILL.md
@@ -107,6 +107,7 @@ Details: [references/auto-selection.md](references/auto-selection.md)
 1. Determine this SKILL.md file's directory path as `SKILL_DIR`
 2. Script path = `${SKILL_DIR}/scripts/<script-name>.ts`
 3. Replace all `${SKILL_DIR}` in this document with the actual path
+4. Resolve `${BUN_X}` runtime: if `bun` installed → `bun`; if `npx` available → `npx -y bun`; else suggest installing bun
 
 **Script Reference**:
 | Script | Purpose |
@@ -209,7 +210,7 @@ Analyze → [Check Existing?] → [Confirm: Style + Reviews] → Storyboard →
 - **Backup rule**: If `characters/characters.png` exists, rename to `characters/characters-backup-YYYYMMDD-HHMMSS.png`
 ```bash
 # Use Reference Sheet Prompt from characters/characters.md
-npx -y bun ${SKILL_DIR}/../baoyu-image-gen/scripts/main.ts \
+${BUN_X} ${SKILL_DIR}/../baoyu-image-gen/scripts/main.ts \
   --promptfiles characters/characters.md \
   --image characters/characters.png --ar 4:3
 ```
@@ -233,7 +234,7 @@ Compress to reduce token usage when used as reference image:
 
 ```bash
 # Example: ALWAYS include --ref for consistency
-npx -y bun ${SKILL_DIR}/../baoyu-image-gen/scripts/main.ts \
+${BUN_X} ${SKILL_DIR}/../baoyu-image-gen/scripts/main.ts \
   --promptfiles prompts/01-page-xxx.md \
   --image 01-page-xxx.png --ar 3:4 \
   --ref characters/characters.png
diff --git a/skills/baoyu-comic/references/workflow.md b/skills/baoyu-comic/references/workflow.md
index 2c39526..40889fc 100644
--- a/skills/baoyu-comic/references/workflow.md
+++ b/skills/baoyu-comic/references/workflow.md
@@ -431,7 +431,7 @@ With confirmed prompts from Step 5/6:
 
 ```bash
 # Each page generation MUST include --ref
-npx -y bun ${SKILL_DIR}/../baoyu-image-gen/scripts/main.ts \
+${BUN_X} ${SKILL_DIR}/../baoyu-image-gen/scripts/main.ts \
   --promptfiles prompts/01-page-xxx.md \
   --image 01-page-xxx.png \
   --ar 3:4 \
@@ -474,7 +474,7 @@ If image generation skill supports `--sessionId`:
 After all images generated:
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/merge-to-pdf.ts <comic-dir>
+${BUN_X} ${SKILL_DIR}/scripts/merge-to-pdf.ts <comic-dir>
 ```
 
 Creates `{topic-slug}.pdf` with all pages as full-page images.
diff --git a/skills/baoyu-compress-image/SKILL.md b/skills/baoyu-compress-image/SKILL.md
index 28cd083..37234de 100644
--- a/skills/baoyu-compress-image/SKILL.md
+++ b/skills/baoyu-compress-image/SKILL.md
@@ -9,7 +9,7 @@ Compresses images using best available tool (sips → cwebp → ImageMagick →
 
 ## Script Directory
 
-Scripts in `scripts/` subdirectory. Replace `${SKILL_DIR}` with this SKILL.md's directory path.
+Scripts in `scripts/` subdirectory. `${SKILL_DIR}` = this SKILL.md's directory path. Resolve `${BUN_X}` runtime: if `bun` installed → `bun`; if `npx` available → `npx -y bun`; else suggest installing bun. Replace `${SKILL_DIR}` and `${BUN_X}` with actual values.
 
 | Script | Purpose |
 |--------|---------|
@@ -48,7 +48,7 @@ test -f "$HOME/.baoyu-skills/baoyu-compress-image/EXTEND.md" && echo "user"
 ## Usage
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/main.ts <input> [options]
+${BUN_X} ${SKILL_DIR}/scripts/main.ts <input> [options]
 ```
 
 ## Options
@@ -67,16 +67,16 @@ npx -y bun ${SKILL_DIR}/scripts/main.ts <input> [options]
 
 ```bash
 # Single file → WebP (replaces original)
-npx -y bun ${SKILL_DIR}/scripts/main.ts image.png
+${BUN_X} ${SKILL_DIR}/scripts/main.ts image.png
 
 # Keep PNG format
-npx -y bun ${SKILL_DIR}/scripts/main.ts image.png -f png --keep
+${BUN_X} ${SKILL_DIR}/scripts/main.ts image.png -f png --keep
 
 # Directory recursive
-npx -y bun ${SKILL_DIR}/scripts/main.ts ./images/ -r -q 75
+${BUN_X} ${SKILL_DIR}/scripts/main.ts ./images/ -r -q 75
 
 # JSON output
-npx -y bun ${SKILL_DIR}/scripts/main.ts image.png --json
+${BUN_X} ${SKILL_DIR}/scripts/main.ts image.png --json
 ```
 
 **Output**:
diff --git a/skills/baoyu-danger-gemini-web/SKILL.md b/skills/baoyu-danger-gemini-web/SKILL.md
index 9bab9ba..d3106fc 100644
--- a/skills/baoyu-danger-gemini-web/SKILL.md
+++ b/skills/baoyu-danger-gemini-web/SKILL.md
@@ -14,7 +14,8 @@ Text/image generation via Gemini Web API. Supports reference images and multi-tu
 **Agent Execution Instructions**:
 1. Determine this SKILL.md file's directory path as `SKILL_DIR`
 2. Script path = `${SKILL_DIR}/scripts/<script-name>.ts`
-3. Replace all `${SKILL_DIR}` in this document with the actual path
+3. Resolve `${BUN_X}` runtime: if `bun` installed → `bun`; if `npx` available → `npx -y bun`; else suggest installing bun
+4. Replace all `${SKILL_DIR}` and `${BUN_X}` in this document with actual values
 
 **Script Reference**:
 | Script | Purpose |
@@ -75,23 +76,23 @@ test -f "$HOME/.baoyu-skills/baoyu-danger-gemini-web/EXTEND.md" && echo "user"
 
 ```bash
 # Text generation
-npx -y bun ${SKILL_DIR}/scripts/main.ts "Your prompt"
-npx -y bun ${SKILL_DIR}/scripts/main.ts --prompt "Your prompt" --model gemini-3-flash
+${BUN_X} ${SKILL_DIR}/scripts/main.ts "Your prompt"
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --prompt "Your prompt" --model gemini-3-flash
 
 # Image generation
-npx -y bun ${SKILL_DIR}/scripts/main.ts --prompt "A cute cat" --image cat.png
-npx -y bun ${SKILL_DIR}/scripts/main.ts --promptfiles system.md content.md --image out.png
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --prompt "A cute cat" --image cat.png
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --promptfiles system.md content.md --image out.png
 
 # Vision input (reference images)
-npx -y bun ${SKILL_DIR}/scripts/main.ts --prompt "Describe this" --reference image.png
-npx -y bun ${SKILL_DIR}/scripts/main.ts --prompt "Create variation" --reference a.png --image out.png
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --prompt "Describe this" --reference image.png
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --prompt "Create variation" --reference a.png --image out.png
 
 # Multi-turn conversation
-npx -y bun ${SKILL_DIR}/scripts/main.ts "Remember: 42" --sessionId session-abc
-npx -y bun ${SKILL_DIR}/scripts/main.ts "What number?" --sessionId session-abc
+${BUN_X} ${SKILL_DIR}/scripts/main.ts "Remember: 42" --sessionId session-abc
+${BUN_X} ${SKILL_DIR}/scripts/main.ts "What number?" --sessionId session-abc
 
 # JSON output
-npx -y bun ${SKILL_DIR}/scripts/main.ts "Hello" --json
+${BUN_X} ${SKILL_DIR}/scripts/main.ts "Hello" --json
 ```
 
 ## Options
diff --git a/skills/baoyu-danger-x-to-markdown/SKILL.md b/skills/baoyu-danger-x-to-markdown/SKILL.md
index 157ee16..06b1e04 100644
--- a/skills/baoyu-danger-x-to-markdown/SKILL.md
+++ b/skills/baoyu-danger-x-to-markdown/SKILL.md
@@ -16,6 +16,7 @@ Scripts located in `scripts/` subdirectory.
 **Path Resolution**:
 1. `SKILL_DIR` = this SKILL.md's directory
 2. Script path = `${SKILL_DIR}/scripts/main.ts`
+3. Resolve `${BUN_X}` runtime: if `bun` installed → `bun`; if `npx` available → `npx -y bun`; else suggest installing bun
 
 ## Consent Requirement
 
@@ -135,10 +136,10 @@ Full reference: [references/config/first-time-setup.md](references/config/first-
 ## Usage
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/main.ts <url>
-npx -y bun ${SKILL_DIR}/scripts/main.ts <url> -o output.md
-npx -y bun ${SKILL_DIR}/scripts/main.ts <url> --download-media
-npx -y bun ${SKILL_DIR}/scripts/main.ts <url> --json
+${BUN_X} ${SKILL_DIR}/scripts/main.ts <url>
+${BUN_X} ${SKILL_DIR}/scripts/main.ts <url> -o output.md
+${BUN_X} ${SKILL_DIR}/scripts/main.ts <url> --download-media
+${BUN_X} ${SKILL_DIR}/scripts/main.ts <url> --json
 ```
 
 ## Options
diff --git a/skills/baoyu-format-markdown/SKILL.md b/skills/baoyu-format-markdown/SKILL.md
index 1a9aa04..f7dd61d 100644
--- a/skills/baoyu-format-markdown/SKILL.md
+++ b/skills/baoyu-format-markdown/SKILL.md
@@ -9,7 +9,7 @@ Transforms plain text or markdown files into well-structured markdown with prope
 
 ## Script Directory
 
-Scripts in `scripts/` subdirectory. Replace `${SKILL_DIR}` with this SKILL.md's directory path.
+Scripts in `scripts/` subdirectory. `${SKILL_DIR}` = this SKILL.md's directory path. Resolve `${BUN_X}` runtime: if `bun` installed → `bun`; if `npx` available → `npx -y bun`; else suggest installing bun. Replace `${SKILL_DIR}` and `${BUN_X}` with actual values.
 
 | Script | Purpose |
 |--------|---------|
@@ -210,7 +210,7 @@ Example:
 After saving, **must** run the formatting script:
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/main.ts {output-file-path} [options]
+${BUN_X} ${SKILL_DIR}/scripts/main.ts {output-file-path} [options]
 ```
 
 **Script Options:**
@@ -229,16 +229,16 @@ npx -y bun ${SKILL_DIR}/scripts/main.ts {output-file-path} [options]
 
 ```bash
 # Default: spacing + emphasis enabled, quotes disabled
-npx -y bun ${SKILL_DIR}/scripts/main.ts article.md
+${BUN_X} ${SKILL_DIR}/scripts/main.ts article.md
 
 # Enable all features including quote replacement
-npx -y bun ${SKILL_DIR}/scripts/main.ts article.md --quotes
+${BUN_X} ${SKILL_DIR}/scripts/main.ts article.md --quotes
 
 # Only fix emphasis issues, skip spacing
-npx -y bun ${SKILL_DIR}/scripts/main.ts article.md --no-spacing
+${BUN_X} ${SKILL_DIR}/scripts/main.ts article.md --no-spacing
 
 # Disable all processing except frontmatter formatting
-npx -y bun ${SKILL_DIR}/scripts/main.ts article.md --no-spacing --no-emphasis
+${BUN_X} ${SKILL_DIR}/scripts/main.ts article.md --no-spacing --no-emphasis
 ```
 
 **Script performs (based on options):**
diff --git a/skills/baoyu-image-gen/SKILL.md b/skills/baoyu-image-gen/SKILL.md
index 9bf5e88..2c9ee6e 100644
--- a/skills/baoyu-image-gen/SKILL.md
+++ b/skills/baoyu-image-gen/SKILL.md
@@ -12,6 +12,7 @@ Official API-based image generation. Supports OpenAI, Google, DashScope (阿里
 **Agent Execution**:
 1. `SKILL_DIR` = this SKILL.md file's directory
 2. Script path = `${SKILL_DIR}/scripts/main.ts`
+3. Resolve `${BUN_X}` runtime: if `bun` installed → `bun`; if `npx` available → `npx -y bun`; else suggest installing bun
 
 ## Step 0: Load Preferences ⛔ BLOCKING
 
@@ -44,34 +45,34 @@ Schema: `references/config/preferences-schema.md`
 
 ```bash
 # Basic
-npx -y bun ${SKILL_DIR}/scripts/main.ts --prompt "A cat" --image cat.png
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --prompt "A cat" --image cat.png
 
 # With aspect ratio
-npx -y bun ${SKILL_DIR}/scripts/main.ts --prompt "A landscape" --image out.png --ar 16:9
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --prompt "A landscape" --image out.png --ar 16:9
 
 # High quality
-npx -y bun ${SKILL_DIR}/scripts/main.ts --prompt "A cat" --image out.png --quality 2k
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --prompt "A cat" --image out.png --quality 2k
 
 # From prompt files
-npx -y bun ${SKILL_DIR}/scripts/main.ts --promptfiles system.md content.md --image out.png
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --promptfiles system.md content.md --image out.png
 
 # With reference images (Google multimodal or OpenAI edits)
-npx -y bun ${SKILL_DIR}/scripts/main.ts --prompt "Make blue" --image out.png --ref source.png
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --prompt "Make blue" --image out.png --ref source.png
 
 # With reference images (explicit provider/model)
-npx -y bun ${SKILL_DIR}/scripts/main.ts --prompt "Make blue" --image out.png --provider google --model gemini-3-pro-image-preview --ref source.png
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --prompt "Make blue" --image out.png --provider google --model gemini-3-pro-image-preview --ref source.png
 
 # Specific provider
-npx -y bun ${SKILL_DIR}/scripts/main.ts --prompt "A cat" --image out.png --provider openai
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --prompt "A cat" --image out.png --provider openai
 
 # DashScope (阿里通义万象)
-npx -y bun ${SKILL_DIR}/scripts/main.ts --prompt "一只可爱的猫" --image out.png --provider dashscope
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --prompt "一只可爱的猫" --image out.png --provider dashscope
 
 # Replicate (google/nano-banana-pro)
-npx -y bun ${SKILL_DIR}/scripts/main.ts --prompt "A cat" --image out.png --provider replicate
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --prompt "A cat" --image out.png --provider replicate
 
 # Replicate with specific model
-npx -y bun ${SKILL_DIR}/scripts/main.ts --prompt "A cat" --image out.png --provider replicate --model google/nano-banana
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --prompt "A cat" --image out.png --provider replicate --model google/nano-banana
 ```
 
 ## Options
@@ -136,10 +137,10 @@ Examples:
 
 ```bash
 # Use Replicate default model
-npx -y bun ${SKILL_DIR}/scripts/main.ts --prompt "A cat" --image out.png --provider replicate
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --prompt "A cat" --image out.png --provider replicate
 
 # Override model explicitly
-npx -y bun ${SKILL_DIR}/scripts/main.ts --prompt "A cat" --image out.png --provider replicate --model google/nano-banana
+${BUN_X} ${SKILL_DIR}/scripts/main.ts --prompt "A cat" --image out.png --provider replicate --model google/nano-banana
 ```
 
 ## Provider Selection
diff --git a/skills/baoyu-markdown-to-html/SKILL.md b/skills/baoyu-markdown-to-html/SKILL.md
index 304eb56..954973d 100644
--- a/skills/baoyu-markdown-to-html/SKILL.md
+++ b/skills/baoyu-markdown-to-html/SKILL.md
@@ -9,7 +9,7 @@ Converts Markdown files to beautifully styled HTML with inline CSS, optimized fo
 
 ## Script Directory
 
-**Agent Execution**: Determine this SKILL.md directory as `SKILL_DIR`, then use `${SKILL_DIR}/scripts/<name>.ts`.
+**Agent Execution**: Determine this SKILL.md directory as `SKILL_DIR`. Resolve `${BUN_X}` runtime: if `bun` installed → `bun`; if `npx` available → `npx -y bun`; else suggest installing bun. Replace `${SKILL_DIR}` and `${BUN_X}` with actual values.
 
 | Script | Purpose |
 |--------|---------|
@@ -97,7 +97,7 @@ test -f "$HOME/.baoyu-skills/baoyu-post-to-wechat/EXTEND.md" && grep -o 'default
 ### Step 2: Convert
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/main.ts <markdown_file> --theme <theme>
+${BUN_X} ${SKILL_DIR}/scripts/main.ts <markdown_file> --theme <theme>
 ```
 
 ### Step 3: Report Result
@@ -107,7 +107,7 @@ Display the output path from JSON result. If backup was created, mention it.
 ## Usage
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/main.ts <markdown_file> [options]
+${BUN_X} ${SKILL_DIR}/scripts/main.ts <markdown_file> [options]
 ```
 
 **Options:**
@@ -144,19 +144,19 @@ npx -y bun ${SKILL_DIR}/scripts/main.ts <markdown_file> [options]
 
 ```bash
 # Basic conversion (uses default theme, removes first heading)
-npx -y bun ${SKILL_DIR}/scripts/main.ts article.md
+${BUN_X} ${SKILL_DIR}/scripts/main.ts article.md
 
 # With specific theme
-npx -y bun ${SKILL_DIR}/scripts/main.ts article.md --theme grace
+${BUN_X} ${SKILL_DIR}/scripts/main.ts article.md --theme grace
 
 # Theme with custom color
-npx -y bun ${SKILL_DIR}/scripts/main.ts article.md --theme modern --color red
+${BUN_X} ${SKILL_DIR}/scripts/main.ts article.md --theme modern --color red
 
 # Keep the first heading in content
-npx -y bun ${SKILL_DIR}/scripts/main.ts article.md --keep-title
+${BUN_X} ${SKILL_DIR}/scripts/main.ts article.md --keep-title
 
 # Override title
-npx -y bun ${SKILL_DIR}/scripts/main.ts article.md --title "My Article"
+${BUN_X} ${SKILL_DIR}/scripts/main.ts article.md --title "My Article"
 ```
 
 ## Output
diff --git a/skills/baoyu-post-to-wechat/SKILL.md b/skills/baoyu-post-to-wechat/SKILL.md
index e8bd4a3..791ac6a 100644
--- a/skills/baoyu-post-to-wechat/SKILL.md
+++ b/skills/baoyu-post-to-wechat/SKILL.md
@@ -11,7 +11,7 @@ description: Posts content to WeChat Official Account (微信公众号) via API
 
 ## Script Directory
 
-**Agent Execution**: Determine this SKILL.md directory as `SKILL_DIR`, then use `${SKILL_DIR}/scripts/<name>.ts`.
+**Agent Execution**: Determine this SKILL.md directory as `SKILL_DIR`, then use `${SKILL_DIR}/scripts/<name>.ts`. Resolve `${BUN_X}` runtime: if `bun` installed → `bun`; if `npx` available → `npx -y bun`; else suggest installing bun.
 
 | Script | Purpose |
 |--------|---------|
@@ -88,7 +88,7 @@ chrome_profile_path: /path/to/chrome/profile
 Before first use, suggest running the environment check. User can skip if they prefer.
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/check-permissions.ts
+${BUN_X} ${SKILL_DIR}/scripts/check-permissions.ts
 ```
 
 Checks: Chrome, profile isolation, Bun, Accessibility, clipboard, paste keystroke, API credentials, Chrome conflicts.
@@ -111,8 +111,8 @@ Checks: Chrome, profile isolation, Bun, Accessibility, clipboard, paste keystrok
 For short posts with multiple images (up to 9):
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/wechat-browser.ts --markdown article.md --images ./images/
-npx -y bun ${SKILL_DIR}/scripts/wechat-browser.ts --title "标题" --content "内容" --image img.png --submit
+${BUN_X} ${SKILL_DIR}/scripts/wechat-browser.ts --markdown article.md --images ./images/
+${BUN_X} ${SKILL_DIR}/scripts/wechat-browser.ts --title "标题" --content "内容" --image img.png --submit
 ```
 
 See [references/image-text-posting.md](references/image-text-posting.md) for details.
@@ -247,7 +247,7 @@ WECHAT_APP_SECRET=<user_input>
 **API method** (accepts `.md` or `.html`):
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/wechat-api.ts <file> --theme <theme> [--color <color>] [--title <title>] [--summary <summary>] [--author <author>] [--cover <cover_path>]
+${BUN_X} ${SKILL_DIR}/scripts/wechat-api.ts <file> --theme <theme> [--color <color>] [--title <title>] [--summary <summary>] [--author <author>] [--cover <cover_path>]
 ```
 
 **CRITICAL**: Always include `--theme` parameter. Never omit it, even if using `default`. Only include `--color` if explicitly set by user or EXTEND.md.
@@ -266,8 +266,8 @@ If script parameters do not expose the two comment fields, still ensure final AP
 **Browser method** (accepts `--markdown` or `--html`):
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/wechat-article.ts --markdown <markdown_file> --theme <theme> [--color <color>]
-npx -y bun ${SKILL_DIR}/scripts/wechat-article.ts --html <html_file>
+${BUN_X} ${SKILL_DIR}/scripts/wechat-article.ts --markdown <markdown_file> --theme <theme> [--color <color>]
+${BUN_X} ${SKILL_DIR}/scripts/wechat-article.ts --html <html_file>
 ```
 
 ### Step 5: Completion Report
diff --git a/skills/baoyu-post-to-wechat/references/article-posting.md b/skills/baoyu-post-to-wechat/references/article-posting.md
index 080e7ee..c0d6c8d 100644
--- a/skills/baoyu-post-to-wechat/references/article-posting.md
+++ b/skills/baoyu-post-to-wechat/references/article-posting.md
@@ -6,13 +6,13 @@ Post markdown articles to WeChat Official Account with full formatting support.
 
 ```bash
 # Post markdown article
-npx -y bun ./scripts/wechat-article.ts --markdown article.md
+${BUN_X} ./scripts/wechat-article.ts --markdown article.md
 
 # With theme
-npx -y bun ./scripts/wechat-article.ts --markdown article.md --theme grace
+${BUN_X} ./scripts/wechat-article.ts --markdown article.md --theme grace
 
 # With explicit options
-npx -y bun ./scripts/wechat-article.ts --markdown article.md --author "作者名" --summary "摘要"
+${BUN_X} ./scripts/wechat-article.ts --markdown article.md --author "作者名" --summary "摘要"
 ```
 
 ## Parameters
diff --git a/skills/baoyu-post-to-wechat/references/image-text-posting.md b/skills/baoyu-post-to-wechat/references/image-text-posting.md
index f04e8c1..38e7d94 100644
--- a/skills/baoyu-post-to-wechat/references/image-text-posting.md
+++ b/skills/baoyu-post-to-wechat/references/image-text-posting.md
@@ -8,13 +8,13 @@ Post image-text messages with multiple images to WeChat Official Account.
 
 ```bash
 # Post with images and markdown file (title/content extracted automatically)
-npx -y bun ./scripts/wechat-browser.ts --markdown source.md --images ./images/
+${BUN_X} ./scripts/wechat-browser.ts --markdown source.md --images ./images/
 
 # Post with explicit title and content
-npx -y bun ./scripts/wechat-browser.ts --title "标题" --content "内容" --image img1.png --image img2.png
+${BUN_X} ./scripts/wechat-browser.ts --title "标题" --content "内容" --image img1.png --image img2.png
 
 # Save as draft
-npx -y bun ./scripts/wechat-browser.ts --markdown source.md --images ./images/ --submit
+${BUN_X} ./scripts/wechat-browser.ts --markdown source.md --images ./images/ --submit
 ```
 
 ## Parameters
diff --git a/skills/baoyu-post-to-x/SKILL.md b/skills/baoyu-post-to-x/SKILL.md
index 48ea876..f4abf1f 100644
--- a/skills/baoyu-post-to-x/SKILL.md
+++ b/skills/baoyu-post-to-x/SKILL.md
@@ -15,6 +15,7 @@ Posts text, images, videos, and long-form articles to X via real Chrome browser
 1. Determine this SKILL.md file's directory path as `SKILL_DIR`
 2. Script path = `${SKILL_DIR}/scripts/<script-name>.ts`
 3. Replace all `${SKILL_DIR}` in this document with the actual path
+4. Resolve `${BUN_X}` runtime: if `bun` installed → `bun`; if `npx` available → `npx -y bun`; else suggest installing bun
 
 **Script Reference**:
 | Script | Purpose |
@@ -69,7 +70,7 @@ test -f "$HOME/.baoyu-skills/baoyu-post-to-x/EXTEND.md" && echo "user"
 Before first use, suggest running the environment check. User can skip if they prefer.
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/check-paste-permissions.ts
+${BUN_X} ${SKILL_DIR}/scripts/check-paste-permissions.ts
 ```
 
 Checks: Chrome, profile isolation, Bun, Accessibility, clipboard, paste keystroke, Chrome conflicts.
@@ -98,7 +99,7 @@ Checks: Chrome, profile isolation, Bun, Accessibility, clipboard, paste keystrok
 Text + up to 4 images.
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/x-browser.ts "Hello!" --image ./photo.png
+${BUN_X} ${SKILL_DIR}/scripts/x-browser.ts "Hello!" --image ./photo.png
 ```
 
 **Parameters**:
@@ -117,7 +118,7 @@ npx -y bun ${SKILL_DIR}/scripts/x-browser.ts "Hello!" --image ./photo.png
 Text + video file.
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/x-video.ts "Check this out!" --video ./clip.mp4
+${BUN_X} ${SKILL_DIR}/scripts/x-video.ts "Check this out!" --video ./clip.mp4
 ```
 
 **Parameters**:
@@ -138,7 +139,7 @@ npx -y bun ${SKILL_DIR}/scripts/x-video.ts "Check this out!" --video ./clip.mp4
 Quote an existing tweet with comment.
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/x-quote.ts https://x.com/user/status/123 "Great insight!"
+${BUN_X} ${SKILL_DIR}/scripts/x-quote.ts https://x.com/user/status/123 "Great insight!"
 ```
 
 **Parameters**:
@@ -157,8 +158,8 @@ npx -y bun ${SKILL_DIR}/scripts/x-quote.ts https://x.com/user/status/123 "Great
 Long-form Markdown articles (requires X Premium).
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/x-article.ts article.md
-npx -y bun ${SKILL_DIR}/scripts/x-article.ts article.md --cover ./cover.jpg
+${BUN_X} ${SKILL_DIR}/scripts/x-article.ts article.md
+${BUN_X} ${SKILL_DIR}/scripts/x-article.ts article.md --cover ./cover.jpg
 ```
 
 **Parameters**:
diff --git a/skills/baoyu-post-to-x/references/articles.md b/skills/baoyu-post-to-x/references/articles.md
index 1626579..a0f0d66 100644
--- a/skills/baoyu-post-to-x/references/articles.md
+++ b/skills/baoyu-post-to-x/references/articles.md
@@ -12,13 +12,13 @@ Publish Markdown articles to X Articles editor with rich text formatting and ima
 
 ```bash
 # Publish markdown article (preview mode)
-npx -y bun ${SKILL_DIR}/scripts/x-article.ts article.md
+${BUN_X} ${SKILL_DIR}/scripts/x-article.ts article.md
 
 # With custom cover image
-npx -y bun ${SKILL_DIR}/scripts/x-article.ts article.md --cover ./cover.jpg
+${BUN_X} ${SKILL_DIR}/scripts/x-article.ts article.md --cover ./cover.jpg
 
 # Actually publish
-npx -y bun ${SKILL_DIR}/scripts/x-article.ts article.md --submit
+${BUN_X} ${SKILL_DIR}/scripts/x-article.ts article.md --submit
 ```
 
 ## Markdown Format
@@ -76,13 +76,13 @@ Convert markdown and inspect structure:
 
 ```bash
 # Get JSON with all metadata
-npx -y bun ${SKILL_DIR}/scripts/md-to-html.ts article.md
+${BUN_X} ${SKILL_DIR}/scripts/md-to-html.ts article.md
 
 # Output HTML only
-npx -y bun ${SKILL_DIR}/scripts/md-to-html.ts article.md --html-only
+${BUN_X} ${SKILL_DIR}/scripts/md-to-html.ts article.md --html-only
 
 # Save HTML to file
-npx -y bun ${SKILL_DIR}/scripts/md-to-html.ts article.md --save-html /tmp/article.html
+${BUN_X} ${SKILL_DIR}/scripts/md-to-html.ts article.md --save-html /tmp/article.html
 ```
 
 JSON output:
@@ -161,7 +161,7 @@ Claude:
 - **No create button**: Ensure X Premium subscription is active
 - **Cover upload fails**: Check file path and format (PNG, JPEG)
 - **Images not inserting**: Verify placeholders exist in pasted content
-- **Content not pasting**: Check HTML clipboard: `npx -y bun ${SKILL_DIR}/scripts/copy-to-clipboard.ts html --file /tmp/test.html`
+- **Content not pasting**: Check HTML clipboard: `${BUN_X} ${SKILL_DIR}/scripts/copy-to-clipboard.ts html --file /tmp/test.html`
 
 ## How It Works
 
diff --git a/skills/baoyu-post-to-x/references/regular-posts.md b/skills/baoyu-post-to-x/references/regular-posts.md
index 51a8977..01eedd9 100644
--- a/skills/baoyu-post-to-x/references/regular-posts.md
+++ b/skills/baoyu-post-to-x/references/regular-posts.md
@@ -9,20 +9,20 @@ If you prefer step-by-step control:
 ### Step 1: Copy Image to Clipboard
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/copy-to-clipboard.ts image /path/to/image.png
+${BUN_X} ${SKILL_DIR}/scripts/copy-to-clipboard.ts image /path/to/image.png
 ```
 
 ### Step 2: Paste from Clipboard
 
 ```bash
 # Simple paste to frontmost app
-npx -y bun ${SKILL_DIR}/scripts/paste-from-clipboard.ts
+${BUN_X} ${SKILL_DIR}/scripts/paste-from-clipboard.ts
 
 # Paste to Chrome with retries
-npx -y bun ${SKILL_DIR}/scripts/paste-from-clipboard.ts --app "Google Chrome" --retries 5
+${BUN_X} ${SKILL_DIR}/scripts/paste-from-clipboard.ts --app "Google Chrome" --retries 5
 
 # Quick paste with shorter delay
-npx -y bun ${SKILL_DIR}/scripts/paste-from-clipboard.ts --delay 200
+${BUN_X} ${SKILL_DIR}/scripts/paste-from-clipboard.ts --delay 200
 ```
 
 ### Step 3: Use Playwright MCP (if Chrome session available)
@@ -59,7 +59,7 @@ mcp__playwright__browser_take_screenshot filename="preview.png"
 User: /post-to-x "Hello from Claude!" --image ./screenshot.png
 
 Claude:
-1. Runs: npx -y bun ${SKILL_DIR}/scripts/x-browser.ts "Hello from Claude!" --image ./screenshot.png
+1. Runs: ${BUN_X} ${SKILL_DIR}/scripts/x-browser.ts "Hello from Claude!" --image ./screenshot.png
 2. Chrome opens with X compose page
 3. Text is typed into editor
 4. Image is copied to clipboard and pasted
@@ -72,7 +72,7 @@ Claude:
 - **Chrome not found**: Set `X_BROWSER_CHROME_PATH` environment variable
 - **Not logged in**: First run opens Chrome - log in manually, cookies are saved
 - **Image paste fails**:
-  - Verify clipboard script: `npx -y bun ${SKILL_DIR}/scripts/copy-to-clipboard.ts image <path>`
+  - Verify clipboard script: `${BUN_X} ${SKILL_DIR}/scripts/copy-to-clipboard.ts image <path>`
   - On macOS, grant "Accessibility" permission to Terminal/iTerm in System Settings > Privacy & Security > Accessibility
   - Keep Chrome window visible and in front during paste operations
 - **osascript permission denied**: Grant Terminal accessibility permissions in System Preferences
diff --git a/skills/baoyu-slide-deck/SKILL.md b/skills/baoyu-slide-deck/SKILL.md
index a83809c..b58efa7 100644
--- a/skills/baoyu-slide-deck/SKILL.md
+++ b/skills/baoyu-slide-deck/SKILL.md
@@ -24,6 +24,7 @@ Transform content into professional slide deck images.
 **Agent Execution Instructions**:
 1. Determine this SKILL.md file's directory path as `SKILL_DIR`
 2. Script path = `${SKILL_DIR}/scripts/<script-name>.ts`
+3. Resolve `${BUN_X}` runtime: if `bun` installed → `bun`; if `npx` available → `npx -y bun`; else suggest installing bun
 
 | Script | Purpose |
 |--------|---------|
@@ -550,8 +551,8 @@ options:
 ### Step 8: Merge to PPTX and PDF
 
 ```bash
-npx -y bun ${SKILL_DIR}/scripts/merge-to-pptx.ts <slide-deck-dir>
-npx -y bun ${SKILL_DIR}/scripts/merge-to-pdf.ts <slide-deck-dir>
+${BUN_X} ${SKILL_DIR}/scripts/merge-to-pptx.ts <slide-deck-dir>
+${BUN_X} ${SKILL_DIR}/scripts/merge-to-pdf.ts <slide-deck-dir>
 ```
 
 ### Step 9: Output Summary
diff --git a/skills/baoyu-url-to-markdown/SKILL.md b/skills/baoyu-url-to-markdown/SKILL.md
index 0ede520..86eaf59 100644
--- a/skills/baoyu-url-to-markdown/SKILL.md
+++ b/skills/baoyu-url-to-markdown/SKILL.md
@@ -14,7 +14,8 @@ Fetches any URL via Chrome CDP and converts HTML to clean markdown.
 **Agent Execution Instructions**:
 1. Determine this SKILL.md file's directory path as `SKILL_DIR`
 2. Script path = `${SKILL_DIR}/scripts/<script-name>.ts`
-3. Replace all `${SKILL_DIR}` in this document with the actual path
+3. Resolve `${BUN_X}` runtime: if `bun` installed → `bun`; if `npx` available → `npx -y bun`; else suggest installing bun
+4. Replace all `${SKILL_DIR}` and `${BUN_X}` in this document with actual values
 
 **Script Reference**:
 | Script | Purpose |
@@ -98,16 +99,16 @@ Full reference: [references/config/first-time-setup.md](references/config/first-
 
 ```bash
 # Auto mode (default) - capture when page loads
-npx -y bun ${SKILL_DIR}/scripts/main.ts <url>
+${BUN_X} ${SKILL_DIR}/scripts/main.ts <url>
 
 # Wait mode - wait for user signal before capture
-npx -y bun ${SKILL_DIR}/scripts/main.ts <url> --wait
+${BUN_X} ${SKILL_DIR}/scripts/main.ts <url> --wait
 
 # Save to specific file
-npx -y bun ${SKILL_DIR}/scripts/main.ts <url> -o output.md
+${BUN_X} ${SKILL_DIR}/scripts/main.ts <url> -o output.md
 
 # Download images and videos to local directories
-npx -y bun ${SKILL_DIR}/scripts/main.ts <url> --download-media
+${BUN_X} ${SKILL_DIR}/scripts/main.ts <url> --download-media
 ```
 
 ## Options
diff --git a/skills/baoyu-xhs-images/references/workflows/prompt-assembly.md b/skills/baoyu-xhs-images/references/workflows/prompt-assembly.md
index 12be2e7..326d661 100644
--- a/skills/baoyu-xhs-images/references/workflows/prompt-assembly.md
+++ b/skills/baoyu-xhs-images/references/workflows/prompt-assembly.md
@@ -167,7 +167,7 @@ When generating multiple images in a series:
 1. **Image 1 (cover)**: Generate without `--ref` — this establishes the visual anchor
 2. **Images 2+**: Always pass image 1 as `--ref` to the image generation skill:
    ```bash
-   npx -y bun ${SKILL_DIR}/scripts/main.ts \
+   ${BUN_X} ${SKILL_DIR}/scripts/main.ts \
      --promptfiles prompts/02-content-xxx.md \
      --ref path/to/01-cover-xxx.png \
      --image 02-content-xxx.png --ar 3:4 --quality 2k