AWS Amazon EC2 Auto Scaling
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For Agents
Create and manage EC2 Auto Scaling groups, scaling policies, scheduled actions, and lifecycle hooks so an agent can keep an EC2 fleet sized to demand and replace unhealthy instances automatically.
Use for: I need to create an Auto Scaling group for my web fleet, Set up a target tracking policy that holds CPU at 50 percent, Attach an Application Load Balancer target group to my Auto Scaling group, Schedule the fleet to scale up before Monday morning peak
Not supported: Does not provision EC2 instances directly, manage Kubernetes node pools, or scale ECS services. Use for EC2 Auto Scaling group capacity management only.
Amazon EC2 Auto Scaling launches and terminates EC2 instances automatically in response to demand, scheduled actions, and instance health checks. The API lets you create Auto Scaling groups, define launch templates and configurations, attach load balancers and target groups, configure scaling policies driven by CloudWatch alarms, and set lifecycle hooks for graceful instance bring-up and tear-down. It is the control plane for keeping a fleet of EC2 instances at the size your workload requires while replacing failed instances and balancing them across Availability Zones.
Install Jentic One Beta
Connect the Amazon EC2 Auto Scaling to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Amazon EC2 Auto Scaling, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.
Two steps, two machines. Install the instance in a safe environment, then register your agent from wherever it runs.
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Step 1: Jentic One Host machine
# On the machine that will host your Jentic One instance:
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh2
Step 2: Agent machine
# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh
jentic register # connects your agent to your Jentic One instanceJentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.
Capabilities
What an agent can do with Amazon EC2 Auto Scaling API.
Create Auto Scaling groups bound to a launch template, with min/max/desired capacity across one or more Availability Zones
Attach Application Load Balancer target groups and Classic Load Balancers to an Auto Scaling group so new instances receive traffic automatically
Configure target tracking, step, and simple scaling policies driven by CloudWatch metrics such as CPU utilisation or request count
Schedule capacity changes ahead of known traffic patterns using PutScheduledUpdateGroupAction
Set instance lifecycle hooks to drain connections or run bootstrapping work before an instance is launched or terminated
Mark instances unhealthy with SetInstanceHealth so Auto Scaling replaces them on the next health check
Enable instance refresh to roll out a new launch template version across the group with a target healthy percentage
Use Cases
Patterns agents use Amazon EC2 Auto Scaling API for, with concrete tasks.
★ Demand-Based Web Fleet Scaling
Run a stateless web tier that grows and shrinks with traffic. Define an Auto Scaling group bound to a launch template, attach an Application Load Balancer target group, and add a target tracking policy that holds average CPU at 50 percent. EC2 Auto Scaling adds instances when demand rises, removes them when it falls, and replaces any that fail an EC2 or ELB health check. Initial setup takes a few hours including launch template, IAM role, and ALB wiring.
Create an Auto Scaling group named web-prod with min 2, desired 4, max 20 across three AZs, attach target group arn:aws:elasticloadbalancing:..., and add a target tracking policy keeping ASGAverageCPUUtilization at 50.
Scheduled Capacity for Predictable Traffic
Pre-warm capacity before a known traffic spike, such as Monday 9am, an end-of-month batch run, or a scheduled marketing send, without paying for unused instances overnight. Use PutScheduledUpdateGroupAction to set min, max, and desired capacity at specific times in cron-style schedules. EC2 Auto Scaling adjusts the group at the scheduled time and lets the regular scaling policies take over once load arrives.
Create a scheduled action on Auto Scaling group web-prod that sets min=10, desired=15 every weekday at 08:30 UTC and reverts to min=2, desired=4 at 19:00 UTC.
Rolling AMI Rollout with Instance Refresh
Deploy a new AMI or launch template version across an Auto Scaling group without manually cycling instances. StartInstanceRefresh replaces instances in batches with a configurable minimum healthy percentage and warm-up period, pausing if health checks fail. Suitable for OS patching, agent upgrades, or rolling out a new application version on long-lived instances.
Update the launch template for web-prod to AMI ami-0abc123, then call StartInstanceRefresh with MinHealthyPercentage=90 and InstanceWarmup=300, polling DescribeInstanceRefreshes until status is Successful.
Agent-Driven Capacity Operator
Give an AI ops agent the ability to react to sustained load anomalies that fall outside static scaling policies, such as a sudden viral mention, an unusual customer cohort, or an upstream incident draining capacity. The agent calls EC2 Auto Scaling through Jentic to inspect group state, adjust desired capacity within configured bounds, kick off an instance refresh, or temporarily suspend scaling during an incident, all behind Jentic-managed AWS credentials so the human operator never hands a long-lived secret to the agent.
Search Jentic for 'set desired capacity on an auto scaling group', load the SetDesiredCapacity schema, and execute it on web-prod with desired=12 after confirming current CPU > 80 percent for 10 minutes.
Key Endpoints
130 endpoints — amazon ec2 auto scaling launches and terminates ec2 instances automatically in response to demand, scheduled actions, and instance health checks.
METHOD
PATH
DESCRIPTION
POST
/#Action=CreateAutoScalingGroup
Create an Auto Scaling group
POST
/#Action=UpdateAutoScalingGroup
Update group capacity, AZs, or launch template
POST
/#Action=DescribeAutoScalingGroups
List Auto Scaling groups and their state
POST
/#Action=SetDesiredCapacity
Set the desired capacity on a group
POST
/#Action=PutScalingPolicy
Create or update a scaling policy
POST
/#Action=PutScheduledUpdateGroupAction
Schedule a capacity change
POST
/#Action=StartInstanceRefresh
Roll out a new launch template version
POST
/#Action=AttachLoadBalancerTargetGroups
Attach ALB/NLB target groups to a group
POST
/#Action=CreateAutoScalingGroup
Create an Auto Scaling group
POST
/#Action=UpdateAutoScalingGroup
Update group capacity, AZs, or launch template
POST
/#Action=DescribeAutoScalingGroups
List Auto Scaling groups and their state
POST
/#Action=SetDesiredCapacity
Set the desired capacity on a group
POST
/#Action=PutScalingPolicy
Create or update a scaling policy
POST
/#Action=PutScheduledUpdateGroupAction
Schedule a capacity change
POST
/#Action=StartInstanceRefresh
Roll out a new launch template version
POST
/#Action=AttachLoadBalancerTargetGroups
Attach ALB/NLB target groups to a group
Why Jentic?
Three things that make agents converge on Jentic-routed access.
Credential isolation
AWS access key ID and secret access key for Amazon EC2 Auto Scaling are stored encrypted in the Jentic vault. Agents receive scoped, short-lived signing credentials and the raw IAM secrets never enter the agent context. Jentic computes the AWS Signature Version 4 signature server-side for every request.
Intent-based discovery
Agents search Jentic by intent (for example, 'create an auto scaling group') and Jentic returns matching Amazon EC2 Auto Scaling operations with their input schemas, the correct AWS service endpoint, and the required IAM action, so the agent can invoke the right call without crawling the AWS docs.
Time to first call
Direct Amazon EC2 Auto Scaling integration: 1-3 days for AWS SDK setup, IAM role configuration, Sigv4 signing, and error handling. Through Jentic: under 1 hour, search, load schema, execute.
Related APIs
Alternatives and complements available in the Jentic catalogue.
FAQs
Specific to using Amazon EC2 Auto Scaling API through Jentic.
What authentication does the Amazon EC2 Auto Scaling API use?
All requests are signed with AWS Signature Version 4 using an AWS access key ID and secret access key, sent in the Authorization header. Through Jentic, those credentials are stored encrypted in the vault and signing happens server-side, so the agent only ever sees a scoped Jentic credential reference.
Can I attach an Application Load Balancer to an Auto Scaling group with this API?
Yes. Use AttachLoadBalancerTargetGroups for ALB and NLB target groups, or AttachLoadBalancers for Classic Load Balancers. Once attached, instances launched by the group are registered with the target group automatically and removed on termination.
What are the rate limits for the Amazon EC2 Auto Scaling API?
EC2 Auto Scaling uses standard AWS service quotas, not a published per-second limit. Requests can be throttled with a Throttling error, and DescribeAutoScalingGroups in particular has lower quotas than mutating actions. Jentic respects the documented exponential-backoff guidance from AWS when retrying.
How do I roll out a new launch template version to an existing Auto Scaling group through Jentic?
Update the group's launch template version with UpdateAutoScalingGroup, then call StartInstanceRefresh with a MinHealthyPercentage and InstanceWarmup that match your tolerance. Through Jentic, search for 'roll out new launch template' and execute the returned operation; Jentic returns the refresh ID so the agent can poll DescribeInstanceRefreshes.
Does EC2 Auto Scaling work with EC2 Spot instances?
Yes. Mixed instance policies on the Auto Scaling group let you combine On-Demand and Spot capacity with allocation strategies like price-capacity-optimized. Configure this through the group's MixedInstancesPolicy when calling CreateAutoScalingGroup or UpdateAutoScalingGroup.
How is Amazon EC2 Auto Scaling priced?
EC2 Auto Scaling itself is free to use; you pay only for the EC2 instances, EBS volumes, CloudWatch alarms, and Elastic Load Balancing capacity it manages on your behalf.
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