Free tool

ECS task role policy generator

Pick the services your ECS calls and get the task role it needs — scoped to the right ARNs, with the reason behind every action.

1. Which thing needs the role?

The compute that makes the calls. It assumes the role; everything else is a resource the role points at.

Principal

Changing this opens that principal’s own page.

2. What does it call?

Only connections the knowledge base records IAM requirements for. Tick what your ECS actually talks to.

DynamoDBThe application in the ECS task reads/writes a DynamoDB table via the AWS SDK
S3The application in the ECS task reads/writes S3 objects via the AWS SDK (e.g. serving user uploads, reading config/assets, writing logs or exports)
Secrets ManagerThe containerized app reads a secret (typically the database credentials for its RDS/RDS Proxy connection, or third-party API keys) from Secrets Manager instead of baking it into the image or a plain environment variable
SNSThe application in the ECS task publishes messages to an SNS topic via the AWS SDK to fan an event out to multiple subscribers
SQSThe application in the ECS task sends or polls SQS messages via the AWS SDK to decouple components (e.g. a worker service draining a queue)

3. Fill in your account (optional)

Leave these blank and the ARNs keep visible placeholders, so a half-finished policy fails instead of quietly granting more than you meant.

Region

Account ID

Role name

Your role

Nothing selected yet, so the role below can be assumed but grants nothing. Tick a service above.

identity-policy.json

{
  "Version": "2012-10-17",
  "Statement": []
}

trust-policy.json

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "ECSAssumeRole",
      "Effect": "Allow",
      "Principal": {
        "Service": "ecs-tasks.amazonaws.com"
      },
      "Action": "sts:AssumeRole"
    }
  ]
}

Before you apply this

These are the actions this integration typically needs — not a least-privilege proof. After you deploy, narrow the policy with IAM Access Analyzer, which generates one from the calls the principal actually made.
No permissions were generated. The role below can be assumed but grants nothing — pick at least one service this principal calls.

Worth knowing about a ECS task role

This is the TASK role — your container's own permissions. The task EXECUTION role is a second, separate role (trusting the same service principal) that the ECS agent uses to pull the image and set up logging; it usually carries AmazonECSTaskExecutionRolePolicy and is not generated here. (Knowledge base, ECS → ECR.)
The SDK inside the container picks up the task role's credentials from the task metadata endpoint automatically.

Grounded in the same data that validates diagrams

Design Beaver models AWS connections so it can tell you when a diagram is wrong. Part of that model is which IAM actions each integration needs and why — researched against AWS documentation, not inferred. This tool reads that data directly, which is why it can explain every statement instead of just emitting one.

It also means the tool knows what it doesn’t know. A connection the knowledge base has no IAM data for is skipped and named, never filled in with a plausible guess. Where an action comes from somewhere other than the knowledge base, it is labelled.

What a ECS task role can be scoped to

ECS assumes this role through the ecs-tasks.amazonaws.com service principal. These are the 5 connections the knowledge base records IAM requirements for:

ECS → DynamoDB

The application in the ECS task reads/writes a DynamoDB table via the AWS SDK

dynamodb:GetItemdynamodb:PutItemdynamodb:Querydynamodb:UpdateItemdynamodb:DeleteItem

Attach an IAM task role to the task definition granting the required DynamoDB actions — the container's SDK picks up the task role credentials from the task metadata endpoint automatically, so no access keys live in the image

ECS → S3

The application in the ECS task reads/writes S3 objects via the AWS SDK (e.g. serving user uploads, reading config/assets, writing logs or exports)

s3:GetObjects3:PutObjects3:ListBucket

Attach an IAM task role to the task definition granting the required S3 actions — the SDK inside the container picks up the task role's temporary credentials automatically, so no long-lived access keys are stored in the image. This is the task role (application permissions), not the execution role (which handles image pull and log setup).

ECS → Secrets Manager

The containerized app reads a secret (typically the database credentials for its RDS/RDS Proxy connection, or third-party API keys) from Secrets Manager instead of baking it into the image or a plain environment variable

secretsmanager:GetSecretValuesecretsmanager:DescribeSecret

Grant secretsmanager:GetSecretValue (and secretsmanager:DescribeSecret) on the specific secret to the task's IAM role — either the task role (the app reads the secret at runtime via the SDK) or the execution role (the task definition's `secrets` block injects the value as an environment variable at container start). Note the injected value is only refreshed when the task restarts, so a rotated secret needs a new task

ECS → SNS

The application in the ECS task publishes messages to an SNS topic via the AWS SDK to fan an event out to multiple subscribers

sns:Publish

Attach an IAM task role granting sns:Publish on the target topic

ECS → SQS

The application in the ECS task sends or polls SQS messages via the AWS SDK to decouple components (e.g. a worker service draining a queue)

sqs:SendMessagesqs:ReceiveMessagesqs:DeleteMessagesqs:GetQueueAttributes

Attach an IAM task role granting the SQS actions the app uses — sqs:SendMessage to produce, or sqs:ReceiveMessage/sqs:DeleteMessage/sqs:GetQueueAttributes to consume

Generate a role for something else

Questions

Where do the actions come from?

From Design Beaver's AWS knowledge base — the same data its validation engine uses to check architecture diagrams. Each connection between two services records the IAM actions that integration needs and the reason it needs them, researched against AWS documentation. Nothing is generated by a model, and the tool refuses to guess: a service pair the knowledge base has no IAM data for is skipped and reported rather than invented.

Is this a least-privilege policy?

No, and it says so on every policy it generates. These are the actions the integration typically needs — a sound starting point, not proof of minimum access. After you deploy, narrow it with IAM Access Analyzer, which generates a policy from the calls the principal actually made. That is the only way to get a genuinely least-privilege result.

How is this different from the other IAM policy generators?

Most of them start from the action catalogue: search 20,000 actions across 400 services and pick the ones you want, which assumes you already know the answer. This one starts from the architecture — this Lambda calls DynamoDB and SQS — and works out the actions from there. It also scopes each statement to the right ARN, so s3:ListBucket lands on the bucket while s3:GetObject lands on the objects inside it.

Does anything I type leave my browser?

No. The generator runs entirely client-side. Bucket names, table names, account IDs and ARNs are never sent anywhere, and there is no signup.

Why are there two policies?

AWS needs both. The trust policy says who may assume the role — the service principal, like lambda.amazonaws.com. The identity policy says what the role may then do. A role with permissions but no trust policy cannot be assumed by anything, and a role with trust but no permissions can be assumed but does nothing.

Draw it instead, and the role attaches itself

Design Beaver knows which connections need a role because it checks them as you draw. Drop an IAM Role node onto a function and the warnings it resolves disappear. Free, in your browser — sign in with Google or GitHub to save your work.

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