### Plan:

1. **Example Creation**:
    - Develop several usage examples, each one demonstrating a different configuration or set of parameters for the `VortexWorkerAgent` class.
  
2. **Documentation**:
    - Create a clear and concise documentation for each method in the class. Ensure that each method's purpose, input parameters, and return values (if any) are described.

3. **Rules and Guidelines**:
    - Establish a set of general usage rules and guidelines for effectively using the `VortexWorkerAgent` class without running into common pitfalls or misconfigurations.

### Code:

#### Examples:

```python
# Example 1: Basic Initialization
agent1 = VortexWorkerAgent(openai_api_key="YOUR_OPENAI_API_KEY")
agent1.run("Help me find resources about renewable energy.")

# Example 2: Custom Name & Role
agent2 = VortexWorkerAgent(openai_api_key="YOUR_OPENAI_API_KEY", worker_name="EcoHelper", worker_role="Researcher")
agent2.run("Fetch me the latest data on solar energy advancements.")

# Example 3: Human-in-the-Loop Configuration
agent3 = VortexWorkerAgent(openai_api_key="YOUR_OPENAI_API_KEY", human_in_the_loop=True)
agent3.run("Provide me with a summary of the top AI advancements in 2023, and if unsure, ask me.")

# Example 4: Custom LLM & Tools Initialization
custom_llm = InMemoryDocstore({ "answer": "This is a custom answer." })
custom_tools = [WebpageQATool(qa_chain=load_qa_with_sources_chain(custom_llm))]

agent4 = VortexWorkerAgent(openai_api_key="YOUR_OPENAI_API_KEY", llm=custom_llm, tools=custom_tools)
agent4.run("What's the answer?")
```

#### Documentation:

```python
class VortexWorkerAgent:
    """An autonomous agent instance that accomplishes complex tasks.

    Args:
        openai_api_key (str): The API key for OpenAI.
        llm (Optional[Union[InMemoryDocstore, ChatOpenAI]]): The Language Model to use. Defaults to ChatOpenAI.
        tools (Optional[List[Tool]]): Tools to be used by the agent. Defaults to a predefined list.
        embedding_size (Optional[int]): Size for embeddings. Defaults to 8192.
        worker_name (Optional[str]): Name of the worker. Defaults to "Swarm Worker AI Assistant".
        worker_role (Optional[str]): Role of the worker. Defaults to "Assistant".
        human_in_the_loop (Optional[bool]): Flag to specify if a human will be in the loop. Defaults to False.
        search_kwargs (dict): Additional keyword arguments for search. Empty by default.
        verbose (Optional[bool]): Verbose flag. Defaults to False.
        chat_history_file (str): File path to store chat history. Defaults to "chat_history.txt".

    Methods:
        add_tool(tool: Tool): Adds a new tool to the agent's toolset.
        run(prompt: str) -> str: Executes a given task or query using the agent.
    """
```

#### Rules and Guidelines:

1. **Mandatory OpenAI API Key**: Always initialize the `VortexWorkerAgent` with a valid OpenAI API key. It's essential for its proper functioning.

2. **Custom LLMs & Tools**: When providing custom LLMs or tools, ensure they are compatible with the system and the rest of the agent's components.

3. **Human-in-the-Loop**: When `human_in_the_loop` is set to `True`, always ensure you have a mechanism to interact with the agent, especially if it prompts for human input.

4. **Verbose Mode**: Turning on the verbose mode (`verbose=True`) can be useful for debugging but might clutter the console during standard operations.

5. **Memory & Performance**: If you're working with large datasets or demanding tasks, ensure you have sufficient computational resources. The agent can be resource-intensive, especially with bigger embedding sizes.

6. **Safety & Security**: Always be cautious about the data you provide and fetch using the agent. Avoid sharing sensitive or personal information unless necessary.

7. **Chat History**: By default, the chat history is saved in a file named "chat_history.txt". Ensure you have the appropriate write permissions in the directory or specify a different path if needed.