Require API key for get_ml_ready and update docs

Author: darshild1024-cpu

README.md

@@ -160,6 +160,7 @@ print(insight["summary"])
 #### `get_ml_ready(series_ids, align="inner", impute="ffill+median", features="default")`
 
 Fetch multiple series, align on date, impute gaps, and add per-series features (lags, rolling stats, MoM/YoY %, z-score).
+Requires API key on a paid plan.
 
 ```python
 df = iq.get_ml_ready(

datasetiq/features.py

@@ -9,6 +9,8 @@
 import pandas as pd
 
 from .client import get
+from .config import get_config
+from .exceptions import AuthenticationError
 
 SeriesLike = Union[str, pd.DataFrame, pd.Series]
 
@@ -234,6 +236,10 @@ def get_ml_ready(
     Returns:
         DataFrame with aligned base columns and optional engineered features.
     """
+    config = get_config()
+    if not config.api_key:
+        raise AuthenticationError("get_ml_ready requires an API key on a paid plan.")
+
     join_how = "inner" if align == "inner" else "outer"
     frames = []
     for series_id in series_ids:

tests/test_features.py

@@ -37,6 +37,7 @@ def test_get_insight_dataframe():
 
 def test_get_ml_ready_with_features(monkeypatch):
     df = _sample_df()
+    iq.configure(api_key="test-key")
 
     def fake_get(series_id, *args, **kwargs):
         return df.rename(columns={"value": "value"})