diff --git a/src-tauri/src/commands.rs b/src-tauri/src/commands.rs
index 2d652f7..030e0ab 100644
--- a/src-tauri/src/commands.rs
+++ b/src-tauri/src/commands.rs
@@ -2578,6 +2578,32 @@ pub async fn scan_project(working_dir: String) -> Result<ProjectScan, String> {
     })
 }
 
+#[tauri::command]
+pub async fn open_binary_file(app: AppHandle, path: String) -> Result<(), String> {
+    use tauri_plugin_opener::OpenerExt;
+
+    #[cfg(target_os = "windows")]
+    {
+        // Convert the WSL Linux path (e.g. /tmp/file.pdf) to a Windows UNC path
+        // (e.g. \\wsl.localhost\Ubuntu\tmp\file.pdf) so the Windows shell can open it.
+        let output = std::process::Command::new("wsl")
+            .args(["wslpath", "-w", &path])
+            .output()
+            .map_err(|e| e.to_string())?;
+        let windows_path = String::from_utf8_lossy(&output.stdout).trim().to_string();
+        app.opener()
+            .open_path(windows_path, None::<&str>)
+            .map_err(|e| e.to_string())
+    }
+
+    #[cfg(not(target_os = "windows"))]
+    {
+        app.opener()
+            .open_path(path, None::<&str>)
+            .map_err(|e| e.to_string())
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -3292,4 +3318,39 @@ gitea: gitea-mcp -t stdio (STDIO) - ✓ Connected"#;
             Some("Indented Heading".to_string())
         );
     }
+
+    // ==================== open_binary_file E2E path conversion tests ====================
+
+    /// Build the wslpath command structure without executing it, for cross-platform CI testing.
+    #[cfg(test)]
+    fn build_wslpath_command(path: &str) -> (String, Vec<String>) {
+        (
+            "wsl".to_string(),
+            vec!["wslpath".to_string(), "-w".to_string(), path.to_string()],
+        )
+    }
+
+    #[test]
+    fn test_e2e_wslpath_command_structure_pdf() {
+        let (command, args) = build_wslpath_command("/tmp/mcp_output_abc123.pdf");
+        assert_eq!(command, "wsl");
+        assert_eq!(args.len(), 3);
+        assert_eq!(args[0], "wslpath");
+        assert_eq!(args[1], "-w");
+        assert_eq!(args[2], "/tmp/mcp_output_abc123.pdf");
+    }
+
+    #[test]
+    fn test_e2e_wslpath_command_structure_audio() {
+        let (command, args) = build_wslpath_command("/tmp/mcp_output_xyz789.mp3");
+        assert_eq!(command, "wsl");
+        assert_eq!(args[2], "/tmp/mcp_output_xyz789.mp3");
+    }
+
+    #[test]
+    fn test_e2e_wslpath_command_structure_preserves_path() {
+        let path = "/home/naomi/documents/report with spaces.pdf";
+        let (_, args) = build_wslpath_command(path);
+        assert_eq!(args[2], path);
+    }
 }
diff --git a/src-tauri/src/lib.rs b/src-tauri/src/lib.rs
index 7cec226..0e1ec59 100644
--- a/src-tauri/src/lib.rs
+++ b/src-tauri/src/lib.rs
@@ -223,6 +223,7 @@ pub fn run() {
             delete_draft,
             delete_all_drafts,
             scan_project,
+            open_binary_file,
         ])
         .run(tauri::generate_context!())
         .expect("error while running tauri application");
diff --git a/src/lib/components/Markdown.svelte b/src/lib/components/Markdown.svelte
index c0fa9ae..0117bfe 100644
--- a/src/lib/components/Markdown.svelte
+++ b/src/lib/components/Markdown.svelte
@@ -2,7 +2,8 @@
   import { marked } from "marked";
   import hljs from "highlight.js";
   import { onMount } from "svelte";
-  import { openUrl, openPath } from "@tauri-apps/plugin-opener";
+  import { openUrl } from "@tauri-apps/plugin-opener";
+  import { invoke } from "@tauri-apps/api/core";
   import { clipboardStore } from "$lib/stores/clipboard";
   import { linkifyFilePaths } from "$lib/utils/filePaths";
 
@@ -148,7 +149,7 @@
 
     const filePath = anchor.dataset.filepath;
     if (filePath) {
-      void openPath(filePath);
+      void invoke("open_binary_file", { path: filePath });
       return;
     }
 
diff --git a/src/lib/components/Markdown.test.ts b/src/lib/components/Markdown.test.ts
index 56b78c5..e2eb441 100644
--- a/src/lib/components/Markdown.test.ts
+++ b/src/lib/components/Markdown.test.ts
@@ -9,7 +9,8 @@
  * - [ ] Code blocks render with syntax highlighting and a copy button
  * - [ ] ||spoiler text|| renders as a hidden span revealed on click
  * - [ ] Search query highlights matching text in non-code content
- * - [ ] Links open in the system browser via the Tauri opener
+ * - [ ] Regular links open in the system browser via the Tauri opener
+ * - [ ] Binary file links invoke open_binary_file (WSL-path-aware) instead of openPath
  */
 
 import { describe, it, expect } from "vitest";