diff --git a/src/commands/install.ts b/src/commands/install.ts
index b4c015e..f747a8b 100644
--- a/src/commands/install.ts
+++ b/src/commands/install.ts
@@ -27,7 +27,9 @@ function isLocalPath(source: string): boolean {
     source.startsWith('/') ||
     source.startsWith('./') ||
     source.startsWith('../') ||
-    source.startsWith('~/')
+    source.startsWith('~/') ||
+    source.startsWith('~\\') ||                   // Windows home directory with backslash
+    /^[a-zA-Z]:[/\\]/.test(source)               // Windows drive (C:/ or C:\)
   );
 }
 
@@ -56,10 +58,11 @@ function getRepoName(repoUrl: string): string | null {
 }
 
 /**
- * Expand ~ to home directory
+ * Expand ~ to home directory and normalize path
  */
 function expandPath(source: string): string {
-  if (source.startsWith('~/')) {
+  // Support both Unix (~/) and Windows (~\) tilde notation
+  if (source.startsWith('~/') || source.startsWith('~\\')) {
     return join(homedir(), source.slice(2));
   }
   return resolve(source);
diff --git a/src/commands/sync.ts b/src/commands/sync.ts
index d8746eb..7ffee43 100644
--- a/src/commands/sync.ts
+++ b/src/commands/sync.ts
@@ -1,5 +1,6 @@
 import { existsSync, readFileSync, writeFileSync, mkdirSync } from 'fs';
-import { dirname, basename } from 'path';
+import { dirname, basename, resolve, join } from 'path';
+import { homedir } from 'os';
 import chalk from 'chalk';
 import { checkbox } from '@inquirer/prompts';
 import { ExitPromptError } from '@inquirer/core';
@@ -12,11 +13,23 @@ export interface SyncOptions {
   output?: string;
 }
 
+/**
+ * Expand ~ to home directory and resolve path
+ */
+function expandPath(path: string): string {
+  // Support both Unix (~/) and Windows (~\) tilde notation
+  if (path.startsWith('~/') || path.startsWith('~\\')) {
+    return join(homedir(), path.slice(2));
+  }
+  return resolve(path);
+}
+
 /**
  * Sync installed skills to a markdown file
  */
 export async function syncAgentsMd(options: SyncOptions = {}): Promise<void> {
-  const outputPath = options.output || 'AGENTS.md';
+  const rawOutputPath = options.output || 'AGENTS.md';
+  const outputPath = expandPath(rawOutputPath);
   const outputName = basename(outputPath);
 
   // Validate output file is markdown