AWS CUR Data Skill
cur-data
Knowledge about AWS Cost and Usage Report data structure, column formats, and analysis patterns
SKILL.md
Full skill instructions
AWS CUR Data Skill
CUR File Formats
The project supports three CUR file formats:
- CSV: Plain text, largest file size
- CSV.GZ: Gzip compressed CSV, smaller
- Parquet: Columnar format, fastest and smallest (recommended)
Column Name Variants
AWS CUR has two naming conventions. The data processor handles both:
| Canonical Name | Old Format | New Format |
|---|---|---|
| cost | lineItem/UnblendedCost | line_item_unblended_cost |
| account_id | lineItem/UsageAccountId | line_item_usage_account_id |
| service | product/ProductName | product_product_name |
| date | lineItem/UsageStartDate | line_item_usage_start_date |
| region | product/Region | product_region |
| line_item_type | lineItem/LineItemType | line_item_line_item_type |
Key Cost Columns
# Unblended cost - actual cost before discounts
line_item_unblended_cost
# Blended cost - averaged across organization
line_item_blended_cost
# Net cost - after discounts applied
line_item_net_unblended_cost
# Usage amount
line_item_usage_amount
Line Item Types
LINE_ITEM_TYPES = {
'Usage': 'Normal usage charges',
'Tax': 'Tax charges',
'Fee': 'AWS fees',
'Refund': 'Refunds/credits',
'Credit': 'Applied credits',
'RIFee': 'Reserved Instance fees',
'DiscountedUsage': 'RI/SP discounted usage',
'SavingsPlanCoveredUsage': 'Savings Plan usage',
'SavingsPlanNegation': 'SP cost adjustment',
'SavingsPlanUpfrontFee': 'SP upfront payment',
'SavingsPlanRecurringFee': 'SP monthly fee',
'BundledDiscount': 'Free tier/bundled',
'EdpDiscount': 'Enterprise discount',
}
Discount Analysis
To identify discounts and credits:
discount_types = ['Credit', 'Refund', 'EdpDiscount', 'BundledDiscount']
discounts = df[df['line_item_type'].isin(discount_types)]
Savings Plan Analysis
Key columns for savings plans:
savings_plan_columns = [
'savings_plan_savings_plan_arn',
'savings_plan_savings_plan_rate',
'savings_plan_used_commitment',
'savings_plan_total_commitment_to_date',
]
Common Aggregations
# Cost by service
df.groupby('service').agg({'cost': 'sum'}).sort_values('cost', ascending=False)
# Cost by account and service
df.groupby(['account_id', 'service']).agg({'cost': 'sum'})
# Daily trends
df.groupby(df['date'].dt.date).agg({'cost': 'sum'})
# Monthly summary
df.groupby(df['date'].dt.to_period('M')).agg({'cost': 'sum'})
Anomaly Detection
The project uses z-score based detection:
mean = daily_costs.mean()
std = daily_costs.std()
z_scores = (daily_costs - mean) / std
anomalies = daily_costs[abs(z_scores) > 2] # 2 std deviations
Mock Data Reference
Test fixtures provide 6 months of data:
- Production (111111111111): 87% of costs, steady growth
- Development (210987654321): 13% of costs, spiky (load testing)
- Services: EC2, RDS, S3, CloudFront, DynamoDB, Lambda
- Regions: us-east-1, us-west-2, eu-west-1, ap-northeast-1, etc.
- Total: ~$6.2M over 182 days
