Install the ECS Agent

Option 1: Daemon service (EC2 capacity)

# Terraform snippet
resource "aws_ecs_task_definition" "clustercost" {
  family                = "clustercost-agent"
  network_mode          = "bridge"
  cpu                   = 256
  memory                = 512
  requires_compatibilities = ["EC2"]
  container_definitions = jsonencode([
    {
      name  = "agent"
      image = "ghcr.io/clustercost/ecs-agent:latest"
      environment = [{ name = "CLUSTERCOST_CLUSTER", value = "payments-prod" }]
    }
  ])
}

Run one copy per instance using an ECS service with the DAEMON scheduling strategy.

Option 2: Sidecar (Fargate)

Add a second container to an existing task definition:

{
  "name": "clustercost-agent",
  "image": "ghcr.io/clustercost/ecs-agent:latest",
  "essential": false,
  "environment": [
    { "name": "CLUSTERCOST_SERVICE", "value": "sync-worker" }
  ]
}

In both cases, grant the task IAM permissions for ecs:Describe* and cloudwatch:GetMetricData so it can resolve usage details and match them to AWS pricing.