docs: improve hello world (#2127)

Author: shahules786

docs/experimental/core_concepts/datasets.md renamed to docs/experimental/explanation/datasets.md

@@ -1,61 +1,58 @@
 # Ragas Experimental
 
+A framework for applying Evaluation-Driven Development (EDD) to AI applications.
+
+The goal of Ragas Experimental is to evolve Ragas into a general-purpose evaluation framework for AI applications. It helps teams design, run, and reason about evaluations across any AI workflow. Beyond tooling, it provides a mental model for thinking about evaluations not just as a diagnostic tool, but as the backbone of iterative improvement.
+
 # ✨ Introduction
 
 
 <div class="grid cards" markdown>
+
 - 🚀 **Tutorials**
 
-    Install with `pip` and get started with Ragas with these tutorials.
+    Step-by-step guides to help you get started with Ragas Experimental. Learn how to evaluate AI applications like RAGs and agents with practical examples.
 
     [:octicons-arrow-right-24: Tutorials](tutorials/index.md)
 
-- 📚 **Core Concepts**
+- 📚 **Explanation**
 
-    In depth explanation and discussion of the concepts and working of different features available in Ragas.
-
-    [:octicons-arrow-right-24: Core Concepts](core_concepts/index.md)
+    A deeper dive into the principles of evaluation and how Ragas Experimental supports evaluation-driven development for AI applications.
 
+    [:octicons-arrow-right-24: Explanation](explanation/index.md)
 
 </div>
 
-## Installation
-
-- Install ragas_experimental from pip
 
-```bash
-pip install ragas_experimental
-```
+## Hello World 👋
 
-- Install from source
+![](hello_world.gif)
 
-```bash
-git clone https://github.com/explodinggradients/ragas
-```
+1\. Install Ragas Experimental with local backend
 
 ```bash
-cd ragas/experimental && pip install -e .
+pip install ragas-experimental && pip install "ragas-experimental[local]"
 ```
 
+2\. Copy this snippet to a file named `hello_world.py` and run `python hello_world.py` 
 
-## Hello World 👋
-
-Copy this snippet to a file named `hello_world.py` and run `python hello_world.py` 
 
 ```python
 import numpy as np
 from ragas_experimental import experiment, Dataset
-from ragas_experimental.metrics import MetricResult, numeric_metric  
-
+from ragas_experimental.metrics import MetricResult, discrete_metric  
 
-@numeric_metric(name="accuracy_score", allowed_values=(0, 1))
+# Define a custom metric for accuracy
+@discrete_metric(name="accuracy_score", allowed_values=["pass", "fail"])
 def accuracy_score(response: str, expected: str):
-    result = 1 if expected.lower().strip() == response.lower().strip() else 0
-    return MetricResult(result=result, reason=f"Match: {result == 1}")
+    result = "pass" if expected.lower().strip() == response.lower().strip() else "fail"
+    return MetricResult(value=result, reason=f"Match: {result == 'pass'}")
 
+# Mock application endpoint that simulates an AI application response
 def mock_app_endpoint(**kwargs) -> str:
     return np.random.choice(["Paris", "4", "Blue Whale", "Einstein", "Python"])
 
+# Create an experiment that uses the mock application endpoint and the accuracy metric
 @experiment()
 async def run_experiment(row):
     response = mock_app_endpoint(query=row.get("query"))
@@ -83,7 +80,13 @@ if __name__ == "__main__":
     results = asyncio.run(run_experiment.arun(dataset, name="first_experiment"))
 ```
 
-View Results 
+3\. Check your current directory structure to see the created dataset and experiment results.
+
+```bash
+tree .
+```
+
+Output:
 
 ```
 ├── datasets
@@ -92,8 +95,12 @@ View Results
     └── first_experiment.csv
 ```
 
-Open the results in a CSV file
+4\. View the results of your first experiment
 
 ```bash
 open experiments/first_experiment.csv
-```
+```
+
+Output:
+
+![](output_first_experiment.png)

docs/experimental/core_concepts/experimentation.md renamed to docs/experimental/explanation/experimentation.md

@@ -38,14 +38,14 @@ class MyBackend(BaseBackend):
 ```toml
 # pyproject.toml
 [project.entry-points."ragas.backends"]
-"my_storage" = "my_package.backend:MyBackend"
+"my_backend" = "my_package.backend:MyBackend"
 ```
 
 **3. Use:**
 ```python
 from ragas_experimental.backends import get_registry
 registry = get_registry()
-backend = registry["my_storage"](connection_string="...")
+backend = registry["my_backend"](connection_string="...")
 ```
 
 ## Required Methods