diff --git a/hooks/hooks.json b/hooks/hooks.json
index 17e0ac8..b0a7fe7 100644
--- a/hooks/hooks.json
+++ b/hooks/hooks.json
@@ -6,7 +6,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "${CLAUDE_PLUGIN_ROOT}/hooks/session-start.sh"
+            "command": "\"${CLAUDE_PLUGIN_ROOT}/hooks/session-start.cmd\""
           }
         ]
       }
diff --git a/hooks/session-start.cmd b/hooks/session-start.cmd
new file mode 100755
index 0000000..4234f7c
--- /dev/null
+++ b/hooks/session-start.cmd
@@ -0,0 +1,63 @@
+:<<"::CMDLITERAL"
+@ECHO OFF
+GOTO :CMDSCRIPT
+::CMDLITERAL
+
+# ==============================================================================
+# Bash/sh section - runs on Unix/Linux/macOS
+# ==============================================================================
+
+set -euo pipefail
+
+# Determine plugin root directory
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]:-$0}")" && pwd)"
+PLUGIN_ROOT="$(cd "${SCRIPT_DIR}/.." && pwd)"
+
+# Check if legacy skills directory exists and build warning
+warning_message=""
+legacy_skills_dir="${HOME}/.config/superpowers/skills"
+if [ -d "$legacy_skills_dir" ]; then
+    warning_message="\n\n<important-reminder>IN YOUR FIRST REPLY AFTER SEEING THIS MESSAGE YOU MUST TELL THE USER:⚠️ **WARNING:** Superpowers now uses Claude Code's skills system. Custom skills in ~/.config/superpowers/skills will not be read. Move custom skills to ~/.claude/skills instead. To make this message go away, remove ~/.config/superpowers/skills</important-reminder>"
+fi
+
+# Read using-superpowers content
+using_superpowers_content=$(cat "${PLUGIN_ROOT}/skills/using-superpowers/SKILL.md" 2>&1 || echo "Error reading using-superpowers skill")
+
+# Escape outputs for JSON
+using_superpowers_escaped=$(echo "$using_superpowers_content" | sed 's/\\/\\\\/g' | sed 's/"/\\"/g' | awk '{printf "%s\\n", $0}')
+warning_escaped=$(echo "$warning_message" | sed 's/\\/\\\\/g' | sed 's/"/\\"/g' | awk '{printf "%s\\n", $0}')
+
+# Output context injection as JSON
+cat <<EOF
+{
+  "hookSpecificOutput": {
+    "hookEventName": "SessionStart",
+    "additionalContext": "<EXTREMELY_IMPORTANT>\nYou have superpowers.\n\n**The content below is from skills/using-superpowers/SKILL.md - your introduction to using skills:**\n\n${using_superpowers_escaped}\n\n${warning_escaped}\n</EXTREMELY_IMPORTANT>"
+  }
+}
+EOF
+
+exit 0
+
+:CMDSCRIPT
+REM ==============================================================================
+REM Windows cmd.exe section - runs on Windows
+REM ==============================================================================
+
+SETLOCAL EnableDelayedExpansion
+
+REM Determine plugin root directory
+SET "SCRIPT_DIR=%~dp0"
+SET "PLUGIN_ROOT=%SCRIPT_DIR%.."
+
+REM Check if legacy skills directory exists and build warning
+SET "warning_message="
+SET "legacy_skills_dir=%USERPROFILE%\.config\superpowers\skills"
+IF EXIST "%legacy_skills_dir%" (
+    SET "warning_message=\n\n<important-reminder>IN YOUR FIRST REPLY AFTER SEEING THIS MESSAGE YOU MUST TELL THE USER:⚠️ **WARNING:** Superpowers now uses Claude Code's skills system. Custom skills in ~/.config/superpowers/skills will not be read. Move custom skills to ~/.claude/skills instead. To make this message go away, remove ~/.config/superpowers/skills</important-reminder>"
+)
+
+REM Call PowerShell to handle the JSON generation (it's much better at this)
+powershell -NoProfile -ExecutionPolicy Bypass -Command "$scriptDir = '%SCRIPT_DIR%'; $pluginRoot = '%PLUGIN_ROOT%'; $warningMessage = '%warning_message%'; $skillFile = Join-Path $pluginRoot 'skills\using-superpowers\SKILL.md'; if (Test-Path $skillFile) { $skillContent = Get-Content -Path $skillFile -Raw -Encoding UTF8 } else { $skillContent = 'Error: using-superpowers skill file not found' }; $contextContent = '<EXTREMELY_IMPORTANT>\nYou have superpowers.\n\n**The content below is from skills/using-superpowers/SKILL.md - your introduction to using skills:**\n\n' + $skillContent + '\n\n' + $warningMessage + '\n</EXTREMELY_IMPORTANT>'; $output = @{ hookSpecificOutput = @{ hookEventName = 'SessionStart'; additionalContext = $contextContent } }; $output | ConvertTo-Json -Depth 10 -Compress:$false"
+
+EXIT /B 0
diff --git a/hooks/session-start.sh b/hooks/session-start.sh
deleted file mode 100755
index b864540..0000000
--- a/hooks/session-start.sh
+++ /dev/null
@@ -1,34 +0,0 @@
-#!/usr/bin/env bash
-# SessionStart hook for superpowers plugin
-
-set -euo pipefail
-
-# Determine plugin root directory
-SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]:-$0}")" && pwd)"
-PLUGIN_ROOT="$(cd "${SCRIPT_DIR}/.." && pwd)"
-
-# Check if legacy skills directory exists and build warning
-warning_message=""
-legacy_skills_dir="${HOME}/.config/superpowers/skills"
-if [ -d "$legacy_skills_dir" ]; then
-    warning_message="\n\n<important-reminder>IN YOUR FIRST REPLY AFTER SEEING THIS MESSAGE YOU MUST TELL THE USER:⚠️ **WARNING:** Superpowers now uses Claude Code's skills system. Custom skills in ~/.config/superpowers/skills will not be read. Move custom skills to ~/.claude/skills instead. To make this message go away, remove ~/.config/superpowers/skills</important-reminder>"
-fi
-
-# Read using-superpowers content
-using_superpowers_content=$(cat "${PLUGIN_ROOT}/skills/using-superpowers/SKILL.md" 2>&1 || echo "Error reading using-superpowers skill")
-
-# Escape outputs for JSON
-using_superpowers_escaped=$(echo "$using_superpowers_content" | sed 's/\\/\\\\/g' | sed 's/"/\\"/g' | awk '{printf "%s\\n", $0}')
-warning_escaped=$(echo "$warning_message" | sed 's/\\/\\\\/g' | sed 's/"/\\"/g' | awk '{printf "%s\\n", $0}')
-
-# Output context injection as JSON
-cat <<EOF
-{
-  "hookSpecificOutput": {
-    "hookEventName": "SessionStart",
-    "additionalContext": "<EXTREMELY_IMPORTANT>\nYou have superpowers.\n\n**The content below is from skills/using-superpowers/SKILL.md - your introduction to using skills:**\n\n${using_superpowers_escaped}\n\n${warning_escaped}\n</EXTREMELY_IMPORTANT>"
-  }
-}
-EOF
-
-exit 0