Task 1.5: Update Provider Factory documentation for key usage

- Added comprehensive module-level docstring explaining provider vs series keys
- Enhanced Loaders class docstring with purpose and attributes documentation
- Added detailed docstring to GetLoader() method with Args/Returns/Raises sections
- Added type hints: Dict[str, Loader] for self.dict and -> None for __init__
- Clarified distinction between provider keys (e.g., 'aniworld.to') and series keys
- No functional changes - existing implementation already correct
- All 34 provider tests pass
- All 16 SeriesApp tests pass
- Updated instructions.md to mark Task 1.5 as completed
- Follows PEP 8 and PEP 257 standards

instructions.md

@@ -379,9 +379,9 @@ conda run -n AniWorld python -m pytest tests/unit/ -k "provider" -v
 
 **Success Criteria:**
 
--   [ ] Provider factory works with `key` identifiers
--   [ ] No breaking changes to provider interface
--   [ ] All provider factory tests pass
+-   [x] Provider factory works with `key` identifiers
+-   [x] No breaking changes to provider interface
+-   [x] All provider factory tests pass
 
 **Test Command:**
 
@@ -389,6 +389,29 @@ conda run -n AniWorld python -m pytest tests/unit/ -k "provider" -v
 conda run -n AniWorld python -m pytest tests/unit/ -k "provider_factory" -v
 ```
 
+**Status:** ✅ COMPLETED
+
+**Implementation Details:**
+
+-   Added comprehensive module-level docstring explaining the distinction between provider keys and series keys
+-   Enhanced `Loaders` class docstring with detailed documentation of its purpose and attributes
+-   Added comprehensive docstring to `GetLoader()` method explaining:
+    -   Provider key vs series key distinction
+    -   Parameter usage and return value
+    -   Raises clause documenting KeyError exception
+    -   Note clarifying the two-level key usage (provider key in factory, series key in providers)
+-   Added type hint `Dict[str, Loader]` to `self.dict` attribute for better type safety
+-   Added return type hint `-> None` to `__init__` method
+-   Verified provider factory already correctly uses `key` for provider identification
+-   Verified provider instances (via Loader interface) use `key` for series identification
+-   No functional changes required - existing implementation was already correct
+-   Documentation now clearly distinguishes between:
+    -   Provider keys: Site identifiers like "aniworld.to" (used by factory)
+    -   Series keys: Unique anime identifiers like "attack-on-titan" (used by providers)
+-   All 34 provider-related tests pass successfully
+-   All 16 SeriesApp tests pass, confirming no breaking changes in Loaders integration
+-   Code follows PEP 8 and PEP 257 standards
+
 ---
 
 ### Phase 2: Core Application Layer

src/core/providers/provider_factory.py

@@ -1,10 +1,56 @@
+"""Provider factory for managing anime content providers.
+
+This module provides a factory class for accessing different anime content
+providers (loaders). The factory uses provider identifiers (keys) to return
+the appropriate provider instance.
+
+Note: The 'key' parameter in this factory refers to the provider identifier
+(e.g., 'aniworld.to'), not to be confused with series keys used within
+providers to identify specific anime series.
+"""
+
+from typing import Dict
+
 from .aniworld_provider import AniworldLoader
 from .base_provider import Loader
 
-class Loaders:
 
-    def __init__(self):
-        self.dict = {"aniworld.to": AniworldLoader()}
+class Loaders:
+    """Factory class for managing and retrieving anime content providers.
+
+    This factory maintains a registry of available providers and provides
+    access to them via provider keys. Each provider implements the Loader
+    interface for searching and downloading anime content.
+
+    Attributes:
+        dict: Dictionary mapping provider keys to provider instances.
+              Provider keys are site identifiers (e.g., 'aniworld.to').
+    """
+
+    def __init__(self) -> None:
+        """Initialize the provider factory with available providers.
+
+        Currently supports:
+        - 'aniworld.to': AniworldLoader for aniworld.to content
+        """
+        self.dict: Dict[str, Loader] = {"aniworld.to": AniworldLoader()}
 
     def GetLoader(self, key: str) -> Loader:
+        """Retrieve a provider instance by its provider key.
+
+        Args:
+            key: Provider identifier (e.g., 'aniworld.to').
+                 This is the site/provider key, not a series key.
+
+        Returns:
+            Loader instance for the specified provider.
+
+        Raises:
+            KeyError: If the provider key is not found in the registry.
+
+        Note:
+            The 'key' parameter here identifies the provider/site, while
+            series-specific operations on the returned Loader use series
+            keys to identify individual anime series.
+        """
         return self.dict[key]