Address Copilot PR review feedback

- JS: Make progressCallback required (not optional) in downloadAndRegisterEpsWithProgress
- C#: Guard null/empty result.Data in DiscoverEpsImpl before deserializing
- Python: Use Callable[[str, float], None] instead of built-in callable
- Rust README: Fix closure to use move + Arc<Mutex> for Send + 'static

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: bmehta001

sdk/cs/src/FoundryLocalManager.cs

@@ -234,7 +234,13 @@ private EpInfo[] DiscoverEpsImpl()
             throw new FoundryLocalException($"Error discovering execution providers: {result.Error}", _logger);
         }
 
-        return JsonSerializer.Deserialize(result.Data!, JsonSerializationContext.Default.EpInfoArray)
+        var data = result.Data;
+        if (string.IsNullOrWhiteSpace(data))
+        {
+            return Array.Empty<EpInfo>();
+        }
+
+        return JsonSerializer.Deserialize(data, JsonSerializationContext.Default.EpInfoArray)
             ?? Array.Empty<EpInfo>();
     }
 

sdk/js/src/foundryLocalManager.ts

@@ -182,8 +182,8 @@ export class FoundryLocalManager {
      * @returns A promise that resolves when all downloads complete.
      */
     public async downloadAndRegisterEpsWithProgress(
-        names?: string[],
-        progressCallback?: (epName: string, percent: number) => void
+        names: string[] | undefined,
+        progressCallback: (epName: string, percent: number) => void
     ): Promise<void> {
         const params: { Params?: { Names: string } } = {};
         if (names && names.length > 0) {
@@ -194,14 +194,12 @@ export class FoundryLocalManager {
             "download_and_register_eps",
             Object.keys(params).length > 0 ? params : undefined,
             (chunk: string) => {
-                if (progressCallback) {
-                    const sepIndex = chunk.indexOf('|');
-                    if (sepIndex >= 0) {
-                        const epName = chunk.substring(0, sepIndex);
-                        const percent = parseFloat(chunk.substring(sepIndex + 1));
-                        if (!isNaN(percent)) {
-                            progressCallback(epName || '', percent);
-                        }
+                const sepIndex = chunk.indexOf('|');
+                if (sepIndex >= 0) {
+                    const epName = chunk.substring(0, sepIndex);
+                    const percent = parseFloat(chunk.substring(sepIndex + 1));
+                    if (!isNaN(percent)) {
+                        progressCallback(epName || '', percent);
                     }
                 }
             }

sdk/python/src/foundry_local_manager.py

@@ -9,7 +9,7 @@
 import logging
 import threading
 
-from typing import Optional
+from typing import Callable, Optional
 
 from .catalog import Catalog
 from .configuration import Configuration
@@ -98,7 +98,7 @@ def discover_eps(self) -> list[EpInfo]:
     def download_and_register_eps(
         self,
         names: Optional[list[str]] = None,
-        progress_callback: Optional[callable] = None,
+        progress_callback: Optional[Callable[[str, float], None]] = None,
     ) -> Optional[EpDownloadResult]:
         """Download and register execution providers (blocking).
 

sdk/rust/README.md

@@ -89,11 +89,15 @@ Use `download_and_register_eps_with_progress` to receive typed `(ep_name, percen
 as each EP downloads (`percent` is 0.0–100.0):
 
 ```rust
-let mut current_ep = String::new();
-manager.download_and_register_eps_with_progress(None, |ep_name, percent| {
-    if ep_name != current_ep {
-        if !current_ep.is_empty() { println!(); }
-        current_ep = ep_name.to_string();
+use std::sync::{Arc, Mutex};
+
+let current_ep = Arc::new(Mutex::new(String::new()));
+let ep = Arc::clone(&current_ep);
+manager.download_and_register_eps_with_progress(None, move |ep_name, percent| {
+    let mut current = ep.lock().unwrap();
+    if ep_name != current.as_str() {
+        if !current.is_empty() { println!(); }
+        *current = ep_name.to_string();
     }
     print!("\r  {}  {:5.1}%", ep_name, percent);
     if percent >= 100.0 { println!(); }