AWS Cost Operations

MCP Server

Command: uvx awslabs.cost-explorer-mcp-server@latest (stdio transport)
Requires: AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY, AWS_REGION (or AWS_PROFILE)
Note: Cost Explorer API charges $0.01 per request — be mindful of query volume

Key Capabilities

Cost breakdown: Spending by service, account, region, or tag
Time series: Daily, monthly, or custom date range cost trends
Forecasts: Predicted spend based on historical patterns
Anomaly detection: Unusual spending spikes
Filtering: Narrow by service (EC2, VPC, TGW, NAT GW, VPN, etc.)

Workflow: Network Cost Analysis

When a user asks "how much is our AWS network costing?":

Total network spend: Cost breakdown for VPC, Transit Gateway, NAT Gateway, VPN, ELB, Direct Connect
Trend: Monthly trend for network services over last 6 months
Top services: Rank network services by spend (NAT GW data processing is often #1)
Per-region: Break down network costs by region
Forecast: Projected network spend for next month
Report: Network cost dashboard with optimization recommendations

Workflow: Cost Anomaly Investigation

When investigating unexpected charges:

Daily breakdown: Get daily costs for the spike period
Service drill-down: Which service caused the spike?
Region check: Was the spike in a specific region?
Correlate: Cross-reference with CloudTrail for resource creation events
Report: Root cause and recommended action

Workflow: Monthly Cost Review

For regular FinOps review:

Month-over-month: Compare current vs previous month spending
Service breakdown: Top 10 services by cost
Network focus: VPC, TGW, NAT GW, VPN, ELB, Direct Connect costs
Growth rate: Percentage change per service
Forecast: Next month projection
Report: Executive cost summary with trends

Common AWS Network Cost Drivers

| Service | Cost Component | Typical Driver | |---------|---------------|----------------| | NAT Gateway | Data processing | $0.045/GB — largest network cost for most | | NAT Gateway | Hourly charge | $0.045/hr per NAT GW | | Transit Gateway | Data processing | $0.02/GB per attachment | | Transit Gateway | Hourly charge | $0.05/hr per attachment | | VPN | Hourly charge | $0.05/hr per VPN connection | | VPN | Data transfer | $0.09/GB outbound | | ELB (ALB) | Hourly + LCU | $0.0225/hr + LCU charges | | ELB (NLB) | Hourly + NLCU | $0.0225/hr + NLCU charges | | Direct Connect | Port hours | $0.03-$0.30/hr depending on speed | | Data Transfer | Cross-AZ | $0.01/GB each direction | | Data Transfer | Cross-Region | $0.02/GB | | Data Transfer | Internet out | $0.09/GB (first 10TB) |

Cost Optimization Tips

| Finding | Recommendation | |---------|---------------| | High NAT GW data processing | Use VPC endpoints for S3/DynamoDB (free) | | Multiple NAT GWs per AZ | Consolidate if traffic allows | | Idle VPN connections | Delete unused VPN tunnels | | Cross-AZ traffic | Co-locate resources in same AZ where possible | | Oversized ELB | Right-size based on actual LCU/NLCU usage | | Unused EIPs | Release unattached Elastic IPs ($0.005/hr) |

Important Rules

Cost Explorer API charges $0.01 per request — batch queries, avoid excessive polling
Data lag — Cost data can be delayed up to 24 hours
Unblended vs amortized — clarify which cost type the user wants
Record in GAIT — log cost investigations for audit trail

Environment Variables

AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY, AWS_REGION (or AWS_PROFILE)