Agent 14 — Cost Estimation

Cloud cost forecast with infrastructure costs, development effort, and ongoing maintenance projections.

File: agents/sdlc/14-cost-estimation.md · Model: Sonnet · Tools: Bash, Read, Write

Purpose

The cost estimation agent produces realistic cost forecasts grounded in current published pricing. Every estimate states its assumptions and variance range explicitly.

Core principle

An estimate without stated assumptions is fiction. State the assumption, state the range, state what would change the number by more than 50%.

What it estimates

• Infrastructure costs — compute, database, storage, bandwidth, CDN
• Development effort — hours/days per pipeline stage
• Ongoing maintenance — monthly operational cost projection
• Scale scenarios — 10x user growth cost impact

Outputs

// .rstack/runs/<run_id>/specs/cost_estimate.json
{
  "assumptions": {
    "monthly_active_users": 1000,
    "region": "us-east-1",
    "uptime_sla": "99.9%"
  },
  "monthly_infrastructure": {
    "compute": "$45 (2x t3.small)",
    "database": "$30 (db.t3.micro RDS PostgreSQL)",
    "storage": "$5 (100GB S3)",
    "total": "$80/month"
  },
  "variance": "Costs increase 4-6x at 10,000 MAU",
  "warnings": ["If media uploads are enabled, S3 + CDN costs increase significantly"]
}