- \n
- Reads CPU usage<\/li>\n
- Checks a condition (CPU > 80%)<\/li>\n
- Executes an action using AWS Lambda<\/li>\n
- Returns a result<\/li>\n<\/ul>\n
This is the foundation<\/strong> of Nova Act\u2013style AI.<\/p>\n
Prerequisites<\/h2>\n
Before starting, ensure you have:<\/p>\n
- \n
- An AWS account<\/li>\n
- Access to AWS Console<\/li>\n
- Region set to us-east-1<\/strong><\/li>\n
- Create the EC2 instance<\/a> and use this instance id for lambda<\/li>\n
- Basic familiarity with AWS navigation<\/li>\n<\/ul>\n
<\/p>\n
STEP 1: Log in to AWS Console<\/h2>\n
- \n
- Open browser<\/li>\n
- Go to: https:\/\/console.aws.amazon.com<\/a><\/li>\n
- Log in with your AWS credentials<\/li>\n
- Set region (top-right) to us-east-1<\/strong><\/li>\n<\/ol>\n
STEP 2: Enable Amazon Bedrock (AI Intelligence)<\/h2>\n
Purpose:<\/strong><\/p>\n
This provides the \u201cthinking capability\u201d for the AI.<\/p>\n
Steps:<\/h3>\n
- \n
- In AWS search bar, type Bedrock<\/strong><\/li>\n
- Open Amazon Bedrock<\/strong><\/a><\/li>\n
- From left menu, click Model access<\/strong><\/li>\n
- Auto Enable:<\/li>\n<\/ol>\n
![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-9-1024x454.png\")
<\/p>\n5. Go from left menu, click Model Catalog<\/strong><\/p>\n
![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-10-1024x460.png\")
<\/p>\n6. Click on Nova 2 Lite<\/strong><\/p>\n
Click on the yellow button: Open in Playground<\/strong><\/p>\n
![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-11-1024x469.png\")
<\/p>\n7. Type the message \u201chello\u201d to test whether Nova 2 Lite is working or not.<\/p>\n
![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-12-1024x462.png\")
<\/p>\nIt\u2019s Working.<\/p>\n
STEP 3: Create IAM Role (Permissions for Actions)<\/h2>\n
Purpose:<\/strong><\/p>\n
Nova Act and lambda requires permission to interact with AWS Services<\/a>.<\/p>\n
- \n
- Search for IAM<\/strong><\/li>\n
- Click Roles<\/strong> \u2192 Create role<\/strong><\/li>\n<\/ol>\n
![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-13-1024x360.png\")
<\/p>\n3. Select:<\/p>\n
- \n
- Trusted entity: AWS service<\/strong><\/li>\n
- Use case: Lambda<\/strong><\/li>\n<\/ul>\n
![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-14-1024x454.png\")
<\/p>\n4. Click Next<\/strong><\/p>\n
Add Permissions:<\/h3>\n
- \n
AWSLambdaBasicExecutionRole<\/code><\/li>\nCloudWatchReadOnlyAccess<\/code><\/li>\n- cloudwatch+ec2<\/li>\n<\/ul>\n
{\r\n \"Version\": \"2012-10-17\",\r\n \"Statement\": [\r\n {\r\n \"Effect\": \"Allow\",\r\n \"Action\": [\r\n \"cloudwatch:GetMetricData\",\r\n \"cloudwatch:GetMetricStatistics\",\r\n \"cloudwatch:ListMetrics\",\r\n \"ec2:DescribeInstances\",\r\n \"ec2:RebootInstances\"\r\n ],\r\n \"Resource\": \"*\"\r\n }\r\n ]\r\n}\r\n<\/pre>\nRole name:<\/p>\n
lambda-execution<\/pre>\n
Click Create role<\/strong><\/p>\n
![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-15-1024x456.png\")
<\/p>\nAI now has permission to perform actions.<\/p>\n
STEP 4 \u2013 Open the Lambda Console<\/strong><\/h2>\n
- \n
- In the AWS Console search bar, type Lambda<\/strong><\/li>\n
- Click on Lambda<\/strong><\/li>\n
- Click Create function<\/strong><\/li>\n<\/ul>\n
![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-16-1024x388.png\")
<\/p>\nFunction Create Settings<\/h3>\n
Select exactly<\/strong> the following options:<\/p>\n
Function name:<\/strong> get_cpu_utilization<\/p>\n
Runtime:<\/strong><\/p>\n
Python 3.12<\/p>\n
Execution role:<\/strong><\/p>\n
Use an existing role<\/p>\n
Role name: lambda-execution<\/strong><\/p>\n
Now click on Create function<\/strong>.<\/p>\n
Wait for a few seconds while the function is being created.<\/p>\n
![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-17-1024x465.png\")
<\/p>\nWhen Lambda Opens \u2013 Go to the Code Tab<\/strong><\/p>\n
As soon as the Lambda function opens, you will see the Code<\/strong> tab.<\/p>\n
There will be some default code already present.<\/p>\n
Delete the default code completely<\/p>\n
Copy\u2013paste the full code below:<\/strong><\/p>\n
import json\r\nimport boto3\r\nfrom datetime import datetime, timedelta, timezone\r\n\r\ncw = boto3.client(\"cloudwatch\")\r\n\r\ndef _extract_from_bedrock_event(event):\r\n \"\"\"\r\n Bedrock Agent action-group (OpenAPI schema) sends:\r\n event[\"requestBody\"][\"content\"][\"application\/json\"][\"properties\"]\r\n \"\"\"\r\n instance_id = None\r\n minutes = 5\r\n\r\n rb = (\r\n event.get(\"requestBody\", {})\r\n .get(\"content\", {})\r\n .get(\"application\/json\", {})\r\n .get(\"properties\", [])\r\n )\r\n\r\n for p in rb:\r\n if p.get(\"name\") == \"instanceId\":\r\n instance_id = p.get(\"value\")\r\n\r\n if p.get(\"name\") == \"minutes\" and p.get(\"value\") is not None:\r\n try:\r\n minutes = int(p.get(\"value\"))\r\n except:\r\n pass\r\n\r\n return instance_id, minutes\r\n\r\n\r\ndef lambda_handler(event, context):\r\n\r\n # Handle BOTH: Bedrock Agent event + manual Lambda test event\r\n if event.get(\"messageVersion\") == \"1.0\":\r\n instance_id, minutes = _extract_from_bedrock_event(event)\r\n else:\r\n instance_id = event.get(\"instanceId\")\r\n minutes = int(event.get(\"minutes\", 5))\r\n\r\n # Compute CPU\r\n cpu_avg = None\r\n datapoints = 0\r\n\r\n if instance_id:\r\n end = datetime.now(timezone.utc)\r\n start = end - timedelta(minutes=minutes)\r\n\r\n resp = cw.get_metric_statistics(\r\n Namespace=\"AWS\/EC2\",\r\n MetricName=\"CPUUtilization\",\r\n Dimensions=[{\"Name\": \"InstanceId\", \"Value\": instance_id}],\r\n StartTime=start,\r\n EndTime=end,\r\n Period=60,\r\n Statistics=[\"Average\"],\r\n )\r\n\r\n dps = sorted(resp.get(\"Datapoints\", []), key=lambda x: x[\"Timestamp\"])\r\n datapoints = len(dps)\r\n cpu_avg = round(dps[-1][\"Average\"], 2) if dps else None\r\n\r\n result = {\r\n \"instanceId\": instance_id or \"\",\r\n \"windowMinutes\": minutes,\r\n \"cpuAvgPercent\": cpu_avg,\r\n \"datapoints\": datapoints,\r\n }\r\n\r\n # Bedrock Agent response format\r\n if event.get(\"messageVersion\") == \"1.0\":\r\n return {\r\n \"messageVersion\": \"1.0\",\r\n \"response\": {\r\n \"actionGroup\": event.get(\"actionGroup\"),\r\n \"apiPath\": event.get(\"apiPath\"),\r\n \"httpMethod\": event.get(\"httpMethod\"),\r\n \"httpStatusCode\": 200,\r\n \"responseBody\": {\r\n \"application\/json\": {\r\n \"body\": json.dumps(result)\r\n }\r\n },\r\n },\r\n \"sessionAttributes\": event.get(\"sessionAttributes\", {}),\r\n \"promptSessionAttributes\": event.get(\"promptSessionAttributes\", {}),\r\n }\r\n\r\n # Manual test output\r\n return result\r\n<\/pre>\nDo NOT Forget to Click the Deploy Button<\/h2>\n
After pasting the code:<\/p>\n
Click the Deploy<\/strong> button (top right)<\/p>\n
If you see \u201cSuccessfully deployed\u201d<\/strong> \u2192 Perfect<\/p>\n
Lambda Test<\/h2>\n
Now we verify whether the Lambda function is working.<\/p>\n
- \n
- Click the Test<\/strong> tab on the Lambda page<\/li>\n
- Click Create new test event<\/strong><\/li>\n<\/ul>\n
Event name:<\/strong><\/p>\n
cpu-test<\/pre>\n
- Click Create new test event<\/strong><\/li>\n<\/ul>\n
- Click on Lambda<\/strong><\/li>\n
- Use case: Lambda<\/strong><\/li>\n<\/ul>\n
- Click Roles<\/strong> \u2192 Create role<\/strong><\/li>\n<\/ol>\n
- Open Amazon Bedrock<\/strong><\/a><\/li>\n
- Create the EC2 instance<\/a> and use this instance id for lambda<\/li>\n
![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-18-1024x455.png\")
<\/p>\n![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-19-1024x470.png\")
<\/p>\n![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-20-1024x366.png\")
<\/p>\n![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/Screenshot-2026-02-11-124027.png\")
<\/p>\n![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-21.png\")
<\/p>\n![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-22.png\")
<\/p>\n![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-23-1024x454.png\")
<\/p>\n![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-25-1024x454.png\")
<\/p>\n![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-26-1024x548.png\")
<\/p>\n![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-27-1024x483.png\")
<\/p>\n![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-28-1024x465.png\")
<\/p>\n![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-30-1024x843.png\")
<\/p>\n![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-31-1024x452.png\")
<\/p>\n![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-32-1024x440.png\")
<\/p>\n![\"\"](\"https:\/\/opstree.com\/blog\/wp-content\/uploads\/2026\/03\/image-33.png\")
<\/p>\n