Optimizing Cloud Costs
Overview
Analyze cloud spending across AWS, GCP, and Azure to identify waste, recommend rightsizing, and generate cost-saving configurations. Covers reserved instances, spot/preemptible workloads, storage tiering, idle resource cleanup, and budget alerting using cloud-native cost management APIs.
Prerequisites
- Cloud provider CLI authenticated with billing/cost-explorer read access
- AWS:
ce:GetCostAndUsage, ec2:DescribeInstances, cloudwatch:GetMetricData permissions
- GCP: Billing Account Viewer and Compute Viewer roles
- Azure: Cost Management Reader role
- Access to current infrastructure-as-code (Terraform, CloudFormation) for rightsizing changes
- At least 30 days of billing data for meaningful analysis
Instructions
- Pull current cost data using cloud cost APIs (
aws ce get-cost-and-usage, gcloud billing budgets list)
- Identify the top 10 cost drivers by service, region, and resource tag
- Detect idle resources: instances with < 5% average CPU over 14 days, unattached EBS volumes, unused Elastic IPs, orphaned snapshots
- Recommend rightsizing: compare instance utilization against available instance types and suggest downsizing
- Evaluate reserved instance or savings plan coverage against on-demand spend; recommend commitments for steady-state workloads
- Identify spot/preemptible candidates: stateless, fault-tolerant workloads (batch jobs, CI runners, dev environments)
- Review storage costs: recommend S3 Intelligent-Tiering, lifecycle policies for infrequent access, or Glacier for archives
- Generate Terraform/IaC changes to implement approved optimizations
- Set up budget alerts with thresholds at 50%, 80%, and 100% of monthly budget
- Create a cost optimization report summarizing findings, savings estimates, and implementation priority
Output
- Cost analysis report with per-service breakdown and savings recommendations
- Terraform/CloudFormation changes for rightsizing and reserved instance purchases
- S3 lifecycle policy configurations for storage tiering
- Budget alert configurations (CloudWatch, GCP Budget, Azure Cost Alerts)
- Cleanup scripts for idle resources (with dry-run mode for safety)
Error Handling
| Error |
Cause |
Solution |
Access Denied on Cost Explorer API |
Missing ce:* IAM permissions |
Attach the AWSBillingReadOnlyAccess managed policy to the IAM user/role |
No billing data available |
Account is too new or cost export not enabled |
Enable Cost Explorer (takes 24h to populate) or set up CUR (Cost and Usage Report) |
Rightsizing recommendation breaks workload |
Instance too small for peak load |
Base sizing on P95 utilization, not average; keep a 20% headroom buffer |
Spot instance terminated mid-job |
Spot capacity reclaimed by provider |
Use spot fleet with diversified instance types and implement checkpointing |
Budget alert not firing |
SNS topic or notification channel misconfigured |
Verify SNS subscription is confirmed and test with a low threshold |
Examples
- "Analyze AWS costs for the last 3 months, identify the top waste areas, and generate a cleanup script for unattached EBS volumes and unused Elastic IPs."
- "Compare on-demand EC2 spend against Savings Plans pricing and recommend 1-year commitments for steady-state workloads."
- "Create S3 lifecycle policies to move objects older than 90 days to Glacier and delete after 365 days across all buckets tagged
env:production."
Resources
1---2name: optimizing-cloud-costs3description: Execute use when you need to work with cloud cost optimization. This skill provides cost analysis and optimization with comprehensive guidance and automation. Trigger with phrases like "optimize costs", "analyze spending", or "reduce costs".4license: MIT5---6# Optimizing Cloud Costs
7
8## Overview
9
10Analyze cloud spending across AWS, GCP, and Azure to identify waste, recommend rightsizing, and generate cost-saving configurations. Covers reserved instances, spot/preemptible workloads, storage tiering, idle resource cleanup, and budget alerting using cloud-native cost management APIs.
11
12## Prerequisites
13
14- Cloud provider CLI authenticated with billing/cost-explorer read access
15- AWS: `ce:GetCostAndUsage`, `ec2:DescribeInstances`, `cloudwatch:GetMetricData` permissions
16- GCP: Billing Account Viewer and Compute Viewer roles
17- Azure: Cost Management Reader role
18- Access to current infrastructure-as-code (Terraform, CloudFormation) for rightsizing changes
19- At least 30 days of billing data for meaningful analysis
20
21## Instructions
22
231. Pull current cost data using cloud cost APIs (`aws ce get-cost-and-usage`, `gcloud billing budgets list`)
242. Identify the top 10 cost drivers by service, region, and resource tag
253. Detect idle resources: instances with < 5% average CPU over 14 days, unattached EBS volumes, unused Elastic IPs, orphaned snapshots
264. Recommend rightsizing: compare instance utilization against available instance types and suggest downsizing
275. Evaluate reserved instance or savings plan coverage against on-demand spend; recommend commitments for steady-state workloads
286. Identify spot/preemptible candidates: stateless, fault-tolerant workloads (batch jobs, CI runners, dev environments)
297. Review storage costs: recommend S3 Intelligent-Tiering, lifecycle policies for infrequent access, or Glacier for archives
308. Generate Terraform/IaC changes to implement approved optimizations
319. Set up budget alerts with thresholds at 50%, 80%, and 100% of monthly budget
3210. Create a cost optimization report summarizing findings, savings estimates, and implementation priority
33
34## Output
35
36- Cost analysis report with per-service breakdown and savings recommendations
37- Terraform/CloudFormation changes for rightsizing and reserved instance purchases
38- S3 lifecycle policy configurations for storage tiering
39- Budget alert configurations (CloudWatch, GCP Budget, Azure Cost Alerts)
40- Cleanup scripts for idle resources (with dry-run mode for safety)
41
42## Error Handling
43
44| Error | Cause | Solution |
45|-------|-------|---------|
46| `Access Denied on Cost Explorer API` | Missing `ce:*` IAM permissions | Attach the `AWSBillingReadOnlyAccess` managed policy to the IAM user/role |
47| `No billing data available` | Account is too new or cost export not enabled | Enable Cost Explorer (takes 24h to populate) or set up CUR (Cost and Usage Report) |
48| `Rightsizing recommendation breaks workload` | Instance too small for peak load | Base sizing on P95 utilization, not average; keep a 20% headroom buffer |
49| `Spot instance terminated mid-job` | Spot capacity reclaimed by provider | Use spot fleet with diversified instance types and implement checkpointing |
50| `Budget alert not firing` | SNS topic or notification channel misconfigured | Verify SNS subscription is confirmed and test with a low threshold |
51
52## Examples
53
54- "Analyze AWS costs for the last 3 months, identify the top waste areas, and generate a cleanup script for unattached EBS volumes and unused Elastic IPs."
55- "Compare on-demand EC2 spend against Savings Plans pricing and recommend 1-year commitments for steady-state workloads."
56- "Create S3 lifecycle policies to move objects older than 90 days to Glacier and delete after 365 days across all buckets tagged `env:production`."
57
58## Resources
59
60- AWS Cost Explorer: https://docs.aws.amazon.com/cost-management/latest/userguide/ce-what-is.html
61- GCP Cost Management: https://cloud.google.com/billing/docs/how-to/budgets
62- Azure Cost Management: https://learn.microsoft.com/en-us/azure/cost-management-billing/
63- FinOps Foundation: https://www.finops.org/framework/
gabrielmoreira