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+# Geo-Analytics API Documentation
+
+## Overview
+
+The Geo-Analytics API is a FastAPI-based service for processing and analyzing geographic data. It provides endpoints for dataset management, regional analytics, trend analysis, and executive summaries.
+
+## Base URL
+
+```
+http://localhost:8000/api
+```
+
+## Authentication
+
+Currently, the API operates in open mode for development. Production deployments should implement authentication (API keys, OAuth2, etc.).
+
+## API Endpoints
+
+### Health Check
+
+#### GET /health
+
+Returns API health status.
+
+**Response:**
+```json
+{
+  "status": "healthy",
+  "version": "1.0.0",
+  "timestamp": "2026-01-17T07:00:00Z"
+}
+```
+
+### Dataset Management
+
+#### GET /datasets
+
+List all available datasets.
+
+**Response:**
+```json
+{
+  "datasets": [
+    {
+      "id": "sample",
+      "name": "Sample Dataset",
+      "records": 100,
+      "columns": ["region", "date", "revenue", "lat", "lon"]
+    }
+  ]
+}
+```
+
+#### POST /datasets/json
+
+Upload a dataset from JSON.
+
+**Query Parameters:**
+- `name` (required): Dataset name
+
+**Request Body:**
+```json
+[
+  {
+    "region": "North",
+    "lat": 40.7128,
+    "lon": -74.0060,
+    "date": "2026-01-01",
+    "revenue": 50000
+  }
+]
+```
+
+**Response:**
+```json
+{
+  "dataset_id": "my-dataset",
+  "records_loaded": 1,
+  "message": "Dataset uploaded successfully"
+}
+```
+
+#### POST /datasets/csv
+
+Upload a dataset from CSV file.
+
+**Query Parameters:**
+- `name` (required): Dataset name
+
+**Request:**
+- Content-Type: multipart/form-data
+- Field: `file` (CSV file)
+
+**Response:**
+```json
+{
+  "dataset_id": "my-csv-dataset",
+  "records_loaded": 250,
+  "message": "Dataset uploaded successfully"
+}
+```
+
+### Regional Analytics
+
+#### GET /analytics/regions
+
+Aggregate data by region.
+
+**Query Parameters:**
+- `dataset_id` (required): Dataset identifier
+- `value_col` (required): Column to aggregate
+- `agg` (optional): Aggregation function (sum, mean, median, count). Default: sum
+
+**Example:**
+```
+GET /api/analytics/regions?dataset_id=sample&value_col=revenue&agg=sum
+```
+
+**Response:**
+```json
+{
+  "data": [
+    {
+      "region": "North",
+      "value": 150000,
+      "lat": 40.7128,
+      "lon": -74.0060
+    },
+    {
+      "region": "South",
+      "value": 120000,
+      "lat": 33.7490,
+      "lon": -84.3880
+    }
+  ],
+  "metadata": {
+    "aggregation": "sum",
+    "value_column": "revenue"
+  }
+}
+```
+
+### Trend Analysis
+
+#### GET /analytics/trends
+
+Analyze temporal trends.
+
+**Query Parameters:**
+- `dataset_id` (required): Dataset identifier
+- `date_col` (required): Date column name
+- `value_col` (required): Value column to analyze
+- `freq` (optional): Time frequency (D=daily, W=weekly, M=monthly). Default: M
+
+**Example:**
+```
+GET /api/analytics/trends?dataset_id=sample&date_col=date&value_col=revenue&freq=M
+```
+
+**Response:**
+```json
+{
+  "trends": [
+    {
+      "period": "2026-01",
+      "value": 450000
+    },
+    {
+      "period": "2026-02",
+      "value": 520000
+    }
+  ],
+  "metadata": {
+    "frequency": "M",
+    "value_column": "revenue"
+  }
+}
+```
+
+### Executive Summary
+
+#### GET /analytics/executive-summary
+
+Generate executive-level insights.
+
+**Query Parameters:**
+- `dataset_id` (required): Dataset identifier
+- `metric` (required): Metric name (e.g., "revenue", "sales")
+- `value_col` (required): Value column
+- `date_col` (optional): Date column for temporal analysis
+
+**Example:**
+```
+GET /api/analytics/executive-summary?dataset_id=sample&metric=revenue&value_col=revenue&date_col=date
+```
+
+**Response:**
+```json
+{
+  "summary": {
+    "metric": "revenue",
+    "total": 2450000,
+    "average": 122500,
+    "top_region": {
+      "name": "North",
+      "value": 580000
+    },
+    "growth_trend": "increasing",
+    "period_covered": {
+      "start": "2026-01-01",
+      "end": "2026-12-31"
+    }
+  }
+}
+```
+
+## Error Responses
+
+All errors follow a consistent format:
+
+```json
+{
+  "error": {
+    "id": "550e8400-e29b-41d4-a716-446655440000",
+    "timestamp": "2026-01-17T07:00:00Z",
+    "status_code": 404,
+    "error_code": "DATASET_NOT_FOUND",
+    "message": "Dataset 'invalid-id' not found",
+    "details": {
+      "dataset_id": "invalid-id"
+    }
+  }
+}
+```
+
+### Common Error Codes
+
+- `DATASET_NOT_FOUND` (404): Requested dataset doesn't exist
+- `INVALID_DATA_FORMAT` (400): Data format validation failed
+- `VALIDATION_ERROR` (422): Request parameters invalid
+- `ANALYTICS_PROCESSING_ERROR` (500): Analytics computation failed
+- `INTERNAL_SERVER_ERROR` (500): Unexpected server error
+- `RATE_LIMIT_EXCEEDED` (429): Too many requests
+
+## Rate Limiting
+
+Currently no rate limiting is enforced. Production deployments should implement rate limiting per client/IP.
+
+## Interactive Documentation
+
+Access interactive API docs:
+- Swagger UI: `http://localhost:8000/docs`
+- ReDoc: `http://localhost:8000/redoc`
+
+## Examples
+
+### Complete Workflow Example
+
+```bash
+# 1. Upload dataset
+curl -X POST "http://localhost:8000/api/datasets/json?name=my-data" \
+  -H "Content-Type: application/json" \
+  -d '[{
+    "region": "East",
+    "lat": 40.7128,
+    "lon": -74.0060,
+    "date": "2026-01-15",
+    "revenue": 75000
+  }]'
+
+# 2. Get regional analytics
+curl "http://localhost:8000/api/analytics/regions?dataset_id=my-data&value_col=revenue&agg=sum"
+
+# 3. Analyze trends
+curl "http://localhost:8000/api/analytics/trends?dataset_id=my-data&date_col=date&value_col=revenue&freq=M"
+
+# 4. Get executive summary
+curl "http://localhost:8000/api/analytics/executive-summary?dataset_id=my-data&metric=revenue&value_col=revenue"
+```
+
+## SDKs and Client Libraries
+
+Python client example:
+
+```python
+import requests
+
+BASE_URL = "http://localhost:8000/api"
+
+# Upload dataset
+data = [
+    {"region": "West", "lat": 34.0522, "lon": -118.2437, 
+     "date": "2026-01-15", "revenue": 85000}
+]
+response = requests.post(
+    f"{BASE_URL}/datasets/json?name=west-region",
+    json=data
+)
+print(response.json())
+
+# Get analytics
+response = requests.get(
+    f"{BASE_URL}/analytics/regions",
+    params={"dataset_id": "west-region", "value_col": "revenue", "agg": "sum"}
+)
+print(response.json())
+```
+
+## Support
+
+For issues or questions:
+- GitHub Issues: https://github.com/mr-adonis-jimenez/Geo-Analytics-API/issues
+- Documentation: https://github.com/mr-adonis-jimenez/Geo-Analytics-API/wiki