Aws

AWS Skill

Hard rules

1. Never destroy data. No delete-*, terminate-*, remove-*, purge-*. No s3 rm. No delete-db-instance. No delete-log-group. If the user needs a destructive command, describe it and let them run it themselves.

2. Always use a read-only profile. Every command gets --profile <readonly>. Never assume the default profile is safe. If no profile is set, ask before running anything.

3. Never fetch secrets. No secretsmanager get-secret-value. No ssm get-parameter --with-decryption. Hand the user the command and let them run it privately.

Step 1 — Establish context

Before any command:

• Profile - which one? Ask if unclear.
• Region - always pass --region explicitly. Never rely on environment defaults.
• Account - if ambiguous, run aws sts get-caller-identity --profile <profile> first.

Step 2 — Read-side commands

Service	Use
S3	ls, cp (download only), head-object
EC2	describe-*
RDS	describe-*
Lambda	list-*, get-*
ECS	describe-*, list-*
CloudWatch	get-metric-statistics, filter-log-events, describe-*
IAM	list-*, get-*, simulate-principal-policy
DynamoDB	describe-*, query, get-item
Cost Explorer	get-cost-and-usage

Step 3 — Format output

--output json    # default
--output table   # human-readable
--query '...'    # filter server-side, not with grep

Example:

aws ec2 describe-instances \
  --profile readonly \
  --region us-east-1 \
  --query 'Reservations[*].Instances[*].{ID:InstanceId,State:State.Name,Type:InstanceType}' \
  --output table

Step 4 — Cost awareness

Flag before running anything expensive.

Situation	Say
DynamoDB full scan	"Full scans consume read capacity on every item. Add --filter-expression or --limit first?"
High-volume CloudWatch log group	"Add --start-time and --end-time to limit data scanned."
Cross-region data transfer	"Moving data across regions costs money. Confirm the target region."

IAM rules

• Run simulate-principal-policy before suggesting any IAM change.
• No * wildcards in resource ARNs unless explicitly asked. Warn about blast radius.
• Never suggest AdministratorAccess or PowerUserAccess. Offer least-privilege alternatives.
• Show policies as JSON blocks so the user can review before applying.

Concerns

Situation	Say
User asks to delete something	Describe the command. Do not run it. Let them verify first.
No --region given	Ask, or use the project's known primary region.
Default profile would be used	"Which profile should I use? Not assuming the default."
Production resources targeted	"This targets production. Confirm before I proceed."
User asks to fetch a secret	"Not retrieving secret values. Run this yourself: aws secretsmanager get-secret-value --secret-id <name>"
Results are paginated	"Page 1 only. Use --starting-token <NextToken> to continue."
Cross-account operation	"This looks cross-account. Confirm the target account ID."
Borrowed or assumed credentials	"Temporary credentials expire. Check aws sts get-caller-identity if you hit auth errors."

Useful patterns

# Who am I?
aws sts get-caller-identity --profile readonly --output table

# Running EC2 instances
aws ec2 describe-instances \
  --profile readonly --region us-east-1 \
  --filters "Name=instance-state-name,Values=running" \
  --query 'Reservations[*].Instances[*].{ID:InstanceId,Type:InstanceType,IP:PrivateIpAddress}' \
  --output table

# Tail Lambda logs
aws logs tail "/aws/lambda/my-function" \
  --profile readonly --region us-east-1 \
  --follow --since 10m

# Check what a role can do
aws iam simulate-principal-policy \
  --profile readonly \
  --policy-source-arn arn:aws:iam::123456789012:role/MyRole \
  --action-names s3:GetObject ec2:DescribeInstances