diff --git a/.ccs.example.json b/.ccs.example.json
index a72ad40b..063c868c 100644
--- a/.ccs.example.json
+++ b/.ccs.example.json
@@ -5,3 +5,4 @@
     "default": "~/.claude/settings.json"
   }
 }
+
diff --git a/README.md b/README.md
index 6d6a24c6..daf093fb 100644
--- a/README.md
+++ b/README.md
@@ -4,10 +4,23 @@
 [![Bash](https://img.shields.io/badge/bash-3.2%2B-blue.svg)](https://www.gnu.org/software/bash/)
 [![GitHub Stars](https://img.shields.io/github/stars/kaitranntt/ccs.svg)](https://github.com/kaitranntt/ccs/stargazers)
 
-> Ultra-simple Claude CLI profile switcher. One command instead of long paths.
+> Switch between Claude Sonnet 4.5 and GLM 4.6 instantly. Use the right model for each task.
 
-**Before**: `claude --settings ~/.claude/glm.settings.json --verbose`
-**After**: `ccs glm --verbose`
+**The Problem**: You have both Claude subscription and GLM Coding Plan. Two scenarios happen daily:
+1. **Rate limits**: Claude hits limit mid-project, you manually edit `~/.claude/settings.json` to switch
+2. **Task optimization**: Complex planning needs Claude Sonnet 4.5's intelligence, but simple coding works fine with GLM 4.6
+
+Manual switching is tedious and error-prone.
+
+**The Solution**:
+```bash
+ccs sonnet    # Complex refactoring? Use Claude Sonnet 4.5
+ccs glm       # Simple bug fix? Use GLM 4.6
+# Hit rate limit? Switch instantly:
+ccs glm       # Continue working with GLM
+```
+
+One command. Zero downtime. No file editing. Right model, right task.
 
 ## Quick Start
 
@@ -39,12 +52,49 @@ ccs sonnet   # Use Sonnet profile
 
 ## Why CCS?
 
-Claude CLI's `--settings` flag is powerful but verbose. CCS gives you friendly aliases.
+**Built for developers with both Claude subscription and GLM Coding Plan.**
 
-**Features**:
-- Single command profile switching
+### Two Real Use Cases
+
+#### 1. Task-Appropriate Model Selection
+**Claude Sonnet 4.5** excels at:
+- Complex architectural decisions
+- System design and planning
+- Debugging tricky issues
+- Code reviews requiring deep reasoning
+
+**GLM 4.6** works great for:
+- Simple bug fixes
+- Straightforward implementations
+- Routine refactoring
+- Documentation writing
+
+**With CCS**: Switch models based on task complexity, maximize quality while managing costs.
+
+```bash
+ccs sonnet    # Planning new feature architecture
+# Got the plan? Implement with GLM:
+ccs glm       # Write the straightforward code
+```
+
+#### 2. Rate Limit Management
+If you have both Claude subscription and GLM Coding Plan, you know the pain:
+- Claude hits rate limit mid-project
+- You manually copy GLM config to `~/.claude/settings.json`
+- 5 minutes later, need to switch back
+- Repeat 10x per day
+
+**CCS solves this**:
+- One command to switch: `ccs glm` or `ccs sonnet`
+- Keep both configs saved as profiles
+- Switch in <1 second
+- No file editing, no copy-paste, no mistakes
+
+### Features
+- Instant profile switching (Claude ↔ GLM)
 - Pass-through all Claude CLI args
-- Zero configuration complexity
+- Smart setup: detects your current provider
+- Auto-creates configs during install
 - No proxies, no magic—just bash + jq
 
 ## Installation
@@ -119,31 +169,71 @@ ccs glm
 
 ## Use Cases
 
-### Claude Subscription + GLM Coding Plan
+### Real Workflow: Task-Based Model Selection
 
-Switch between Claude sub and GLM plan:
+**Scenario**: Building a new payment integration feature
 
+```bash
+# Step 1: Architecture & Planning (needs Claude's intelligence)
+ccs sonnet
+/plan "Design payment integration with Stripe, handle webhooks, errors, retries"
+# → Claude Sonnet 4.5 thinks deeply about edge cases, security, architecture
+
+# Step 2: Implementation (straightforward coding, use GLM)
+ccs glm
+/code "implement the payment webhook handler from the plan"
+# → GLM 4.6 writes the code efficiently, saves Claude usage
+
+# Step 3: Code Review (needs deep analysis)
+ccs sonnet
+/review "check the payment handler for security issues"
+# → Claude Sonnet 4.5 catches subtle vulnerabilities
+
+# Step 4: Bug Fixes (simple)
+ccs glm
+/fix "update error message formatting"
+# → GLM 4.6 handles routine fixes
+```
+
+**Result**: Best model for each task, lower costs, better quality.
+
+### Real Workflow: Rate Limit Management
+
+```bash
+# Working on complex refactoring with Claude
+ccs sonnet
+/plan "refactor authentication system"
+
+# Claude hits rate limit mid-task
+# → Error: Rate limit exceeded
+
+# Switch to GLM instantly
+ccs glm
+# Continue working without interruption
+
+# Rate limit resets? Switch back
+ccs sonnet
+```
+
+### Configuration Examples
+
+**Standard setup** (Claude sub + GLM):
 ```json
 {
   "profiles": {
-    "claude": "~/.claude/claude-sub.settings.json",
     "glm": "~/.claude/glm.settings.json",
+    "sonnet": "~/.claude/sonnet.settings.json",
     "default": "~/.claude/settings.json"
   }
 }
 ```
 
-```bash
-ccs claude   # Use Claude subscription
-ccs glm      # Use GLM coding plan
-```
-
-### Different Models
-
+**Advanced setup** (multiple providers):
 ```json
 {
   "profiles": {
     "sonnet": "~/.claude/sonnet.settings.json",
+    "glm": "~/.claude/glm.settings.json",
     "haiku": "~/.claude/haiku.settings.json",
     "default": "~/.claude/settings.json"
   }
diff --git a/install.sh b/install.sh
index 4d423300..8df38f2a 100755
--- a/install.sh
+++ b/install.sh
@@ -60,26 +60,155 @@ fi
 
 echo "✅ Installation complete!"
 echo ""
-echo "Next steps:"
-if [[ ! -f "$HOME/.ccs.json" ]]; then
-  if [[ -f "$SCRIPT_DIR/.ccs.example.json" ]]; then
-    echo "1. Copy example config: cp $SCRIPT_DIR/.ccs.example.json ~/.ccs.json"
+
+# Smart setup: detect current provider and help create profiles
+CLAUDE_DIR="$HOME/.claude"
+CURRENT_SETTINGS="$CLAUDE_DIR/settings.json"
+GLM_SETTINGS="$CLAUDE_DIR/glm.settings.json"
+SONNET_SETTINGS="$CLAUDE_DIR/sonnet.settings.json"
+
+# Detect current provider
+CURRENT_PROVIDER="unknown"
+if [[ -f "$CURRENT_SETTINGS" ]]; then
+  if grep -q "api.z.ai" "$CURRENT_SETTINGS" 2>/dev/null || grep -q "glm-4" "$CURRENT_SETTINGS" 2>/dev/null; then
+    CURRENT_PROVIDER="glm"
+  elif grep -q "ANTHROPIC_BASE_URL" "$CURRENT_SETTINGS" 2>/dev/null && ! grep -q "api.z.ai" "$CURRENT_SETTINGS" 2>/dev/null; then
+    CURRENT_PROVIDER="custom"
   else
-    echo "1. Create config at ~/.ccs.json:"
-    echo "   {"
-    echo "     \"profiles\": {"
-    echo "       \"glm\": \"~/.claude/glm.settings.json\","
-    echo "       \"sonnet\": \"~/.claude/sonnet.settings.json\","
-    echo "       \"default\": \"~/.claude/settings.json\""
-    echo "     }"
-    echo "   }"
+    CURRENT_PROVIDER="claude"
   fi
-  echo "2. Edit ~/.ccs.json with your profile mappings"
-  echo "3. Run: ccs [profile]"
-else
-  echo "1. Config already exists at ~/.ccs.json"
-  echo "2. Run: ccs [profile]"
 fi
+
+# Check for existing profile files
+HAS_GLM=false
+HAS_SONNET=false
+[[ -f "$GLM_SETTINGS" ]] && HAS_GLM=true
+[[ -f "$SONNET_SETTINGS" ]] && HAS_SONNET=true
+
+# Smart setup guidance
+if [[ "$CURRENT_PROVIDER" != "unknown" ]]; then
+  echo "🔍 Detected current provider: $CURRENT_PROVIDER"
+  echo ""
+fi
+
+# Offer to create missing profiles
+if [[ "$HAS_GLM" == false ]] || [[ "$HAS_SONNET" == false ]]; then
+  echo "📝 Setup wizard: Creating profile files..."
+  echo ""
+
+  # Create GLM profile if missing
+  if [[ "$HAS_GLM" == false ]]; then
+    if [[ "$CURRENT_PROVIDER" == "glm" ]]; then
+      echo "✓ Copying current GLM config to profile..."
+      cp "$CURRENT_SETTINGS" "$GLM_SETTINGS"
+      echo "  Created: $GLM_SETTINGS"
+    else
+      echo "Creating GLM profile template at $GLM_SETTINGS"
+      # Preserve user's existing env vars if they exist
+      if [[ -f "$CURRENT_SETTINGS" ]] && command -v jq &> /dev/null; then
+        # Merge user's env with GLM essentials (atomic operation)
+        if jq '.env |= (. // {}) + {
+          "ANTHROPIC_BASE_URL": "https://api.z.ai/api/anthropic",
+          "ANTHROPIC_AUTH_TOKEN": "YOUR_GLM_API_KEY_HERE",
+          "ANTHROPIC_MODEL": "glm-4.6"
+        }' "$CURRENT_SETTINGS" > "$GLM_SETTINGS.tmp" 2>/dev/null; then
+          mv "$GLM_SETTINGS.tmp" "$GLM_SETTINGS"
+        else
+          rm -f "$GLM_SETTINGS.tmp"
+          echo "  ℹ️  jq failed, using basic template"
+          # Fallback to minimal template
+          cat > "$GLM_SETTINGS" << 'EOF'
+{
+  "env": {
+    "ANTHROPIC_BASE_URL": "https://api.z.ai/api/anthropic",
+    "ANTHROPIC_AUTH_TOKEN": "YOUR_GLM_API_KEY_HERE",
+    "ANTHROPIC_MODEL": "glm-4.6"
+  }
+}
+EOF
+        fi
+      else
+        # Minimal GLM template
+        cat > "$GLM_SETTINGS" << 'EOF'
+{
+  "env": {
+    "ANTHROPIC_BASE_URL": "https://api.z.ai/api/anthropic",
+    "ANTHROPIC_AUTH_TOKEN": "YOUR_GLM_API_KEY_HERE",
+    "ANTHROPIC_MODEL": "glm-4.6"
+  }
+}
+EOF
+      fi
+      echo "  Created: $GLM_SETTINGS"
+      echo "  ⚠️  Edit this file and replace YOUR_GLM_API_KEY_HERE with your actual GLM API key"
+    fi
+    echo ""
+  fi
+
+  # Create Sonnet profile if missing
+  if [[ "$HAS_SONNET" == false ]]; then
+    if [[ "$CURRENT_PROVIDER" == "claude" ]]; then
+      echo "✓ Copying current Claude config to profile..."
+      cp "$CURRENT_SETTINGS" "$SONNET_SETTINGS"
+      echo "  Created: $SONNET_SETTINGS"
+    else
+      echo "Creating Claude Sonnet profile template at $SONNET_SETTINGS"
+      # Preserve user's existing settings, remove GLM-specific fields
+      if [[ -f "$CURRENT_SETTINGS" ]] && command -v jq &> /dev/null; then
+        # Remove GLM-specific env vars, keep user's other settings (atomic)
+        if jq 'del(.env.ANTHROPIC_BASE_URL, .env.ANTHROPIC_AUTH_TOKEN, .env.ANTHROPIC_MODEL) |
+            if (.env | length) == 0 then .env = {} else . end' "$CURRENT_SETTINGS" > "$SONNET_SETTINGS.tmp" 2>/dev/null; then
+          mv "$SONNET_SETTINGS.tmp" "$SONNET_SETTINGS"
+        else
+          rm -f "$SONNET_SETTINGS.tmp"
+          echo "  ℹ️  jq failed, using basic template"
+          # Fallback to minimal template
+          cat > "$SONNET_SETTINGS" << 'EOF'
+{
+  "env": {}
+}
+EOF
+        fi
+      else
+        # Minimal Claude template (uses default authentication)
+        cat > "$SONNET_SETTINGS" << 'EOF'
+{
+  "env": {}
+}
+EOF
+      fi
+      echo "  Created: $SONNET_SETTINGS"
+      echo "  ℹ️  This uses your Claude subscription (no API key needed)"
+    fi
+    echo ""
+  fi
+fi
+
+# Auto-create ~/.ccs.json if missing (atomic operation)
+if [[ ! -f "$HOME/.ccs.json" ]]; then
+  echo "Creating ~/.ccs.json config..."
+  cat > "$HOME/.ccs.json.tmp" << 'EOF'
+{
+  "profiles": {
+    "glm": "~/.claude/glm.settings.json",
+    "sonnet": "~/.claude/sonnet.settings.json",
+    "default": "~/.claude/settings.json"
+  }
+}
+EOF
+  # Atomic move only if file still doesn't exist (prevents race condition)
+  if mv -n "$HOME/.ccs.json.tmp" "$HOME/.ccs.json" 2>/dev/null; then
+    echo "  ✓ Created: ~/.ccs.json"
+  else
+    rm -f "$HOME/.ccs.json.tmp"
+    echo "  ℹ️  Config already exists"
+  fi
+  echo ""
+fi
+
+echo "✅ Setup complete!"
+echo ""
+echo "Quick start:"
 echo ""
 echo "Example:"
 echo "  ccs           # Uses default profile"