Add ImageGenService docstrings

src/pipecat/services/image_service.py

@@ -4,6 +4,12 @@
 # SPDX-License-Identifier: BSD 2-Clause License
 #
 
+"""Image generation service implementation.
+
+Provides base functionality for AI-powered image generation services that convert
+text prompts into images.
+"""
+
 from abc import abstractmethod
 from typing import AsyncGenerator
 
@@ -13,15 +19,46 @@ from pipecat.services.ai_service import AIService
 
 
 class ImageGenService(AIService):
+    """Base class for image generation services.
+
+    Processes TextFrames by using their content as prompts for image generation.
+    Subclasses must implement the run_image_gen method to provide actual image
+    generation functionality using their specific AI service.
+
+    Args:
+            **kwargs: Additional arguments passed to the parent AIService.
+    """
+
     def __init__(self, **kwargs):
         super().__init__(**kwargs)
 
     # Renders the image. Returns an Image object.
     @abstractmethod
     async def run_image_gen(self, prompt: str) -> AsyncGenerator[Frame, None]:
+        """Generate an image from a text prompt.
+
+        This method must be implemented by subclasses to provide actual image
+        generation functionality using their specific AI service.
+
+        Args:
+            prompt: The text prompt to generate an image from.
+
+        Yields:
+            Frame: Frames containing the generated image (typically ImageRawFrame
+                or URLImageRawFrame).
+        """
         pass
 
     async def process_frame(self, frame: Frame, direction: FrameDirection):
+        """Process frames for image generation.
+
+        TextFrames are used as prompts for image generation, while other frames
+        are passed through unchanged.
+
+        Args:
+            frame: The frame to process.
+            direction: The direction of frame processing.
+        """
         await super().process_frame(frame, direction)
 
         if isinstance(frame, TextFrame):