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+(api)=
+
+# API reference
+
+This section provides comprehensive API documentation for all PyAthena classes and functions, organized by functionality.
+
+```{toctree}
+:maxdepth: 2
+:caption: API Documentation:
+
+api/connection
+api/converters
+api/utilities
+api/errors
+api/filesystem
+api/models
+api/sqlalchemy
+api/pandas
+api/arrow
+api/polars
+api/s3fs
+api/spark
+```
+
+## Quick reference
+
+### Core functionality
+
+- {ref}`api_connection` - Connection management and basic cursors
+- {ref}`api_converters` - Data type conversion and parameter formatting
+- {ref}`api_utilities` - Utility functions and base classes
+- {ref}`api_errors` - Exception handling and error classes
+
+### Infrastructure
+
+- {ref}`api_filesystem` - S3 filesystem integration and object management
+- {ref}`api_models` - Athena query execution and metadata models
+
+### Specialized integrations
+
+- {ref}`api_sqlalchemy` - SQLAlchemy dialect implementations
+- {ref}`api_pandas` - pandas DataFrame integration
+- {ref}`api_arrow` - Apache Arrow columnar data integration
+- {ref}`api_polars` - Polars DataFrame integration (no pyarrow required)
+- {ref}`api_s3fs` - Lightweight S3FS-based cursor (no pandas/pyarrow required)
+- {ref}`api_spark` - Apache Spark integration for big data processing