docs: improve tool documentation and examples

- Update SerperDevTool documentation with accurate parameters and JSON response format
- Enhance XMLSearchTool and MDXSearchTool docs with RAG capabilities and required parameters
- Fix code block formatting across multiple tool documentation files
- Add clarification about environment variables and configuration
- Validate all examples against actual implementations
- Successfully tested with mkdocs build

Co-Authored-By: Joe Moura <joao@crewai.com>

docs/tools/dalletool.mdx

@@ -22,7 +22,7 @@ pip install 'crewai[tools]'
 
 Remember that when using this tool, the text must be generated by the Agent itself. The text must be a description of the image you want to generate.
 
-```python Code
+```python
 from crewai_tools import DallETool
 
 Agent(
@@ -31,9 +31,16 @@ Agent(
 )
 ```
 
-If needed you can also tweak the parameters of the DALL-E model by passing them as arguments to the `DallETool` class. For example:
+## Arguments
 
-```python Code
+- `model`: The DALL-E model to use (e.g., "dall-e-3")
+- `size`: Image size (e.g., "1024x1024")
+- `quality`: Image quality ("standard" or "hd")
+- `n`: Number of images to generate
+
+## Configuration Example
+
+```python
 from crewai_tools import DallETool
 
 dalle_tool = DallETool(model="dall-e-3",
@@ -48,4 +55,4 @@ Agent(
 ```
 
 The parameters are based on the `client.images.generate` method from the OpenAI API. For more information on the parameters, 
-please refer to the [OpenAI API documentation](https://platform.openai.com/docs/guides/images/introduction?lang=python).
+please refer to the [OpenAI API documentation](https://platform.openai.com/docs/guides/images/introduction?lang=python).