Core Skills in the AWS Agent Toolkit: Complete Guide to the aws-core Plugin

The AWS Agent Toolkit provides 15 core skills through the aws-core plugin, each defined as a self-contained markdown document (SKILL.md) that enables AI agents to perform authenticated AWS operations across serverless, containers, observability, and cost optimization.

The aws/agent-toolkit-for-aws repository delivers these core skills as the primary interface between AI coding agents—such as Claude Code, Codex, and Cursor—and AWS services. Each skill is a modular package containing step-by-step instructions, reference documentation, and reusable assets that agents load on demand to execute specific AWS tasks.

What Are Core Skills in the AWS Agent Toolkit?

Core skills are self-contained capability modules packaged under the aws-core plugin in the aws/agent-toolkit-for-aws repository. Each skill follows a standardized structure centered on a SKILL.md file that contains concise descriptions, procedural instructions, and links to reference materials.

According to the source code, these skills reside in plugins/aws-core/skills/ with each subdirectory representing a distinct functional domain. The agent loads these markdown definitions dynamically, retrieving only the relevant guidance for the current task to minimize context noise and ensure up-to-date best practices.

Complete List of Core Skills by Domain

The aws-core plugin ships 15 distinct skills organized across infrastructure, security, SDKs, and operations:

Authentication and Security

• Signing‑in to AWS (signing-in-to-aws): Authenticate agents with AWS credentials and configure MCP server sessions. Defined in plugins/aws-core/skills/signing-in-to-aws/SKILL.md.

• AWS IAM (aws-iam): Build policies, roles, and permission boundaries with guardrails. Source: plugins/aws-core/skills/aws-iam/SKILL.md.

• AWS Secrets Manager (aws-secrets-manager): Store, retrieve, and rotate secrets securely. Located in plugins/aws-core/skills/aws-secrets-manager/SKILL.md.

Compute and Serverless

• AWS Serverless (aws-serverless): Create, deploy, and troubleshoot Lambda functions, API Gateway, and Step Functions. Reference: plugins/aws-core/skills/aws-serverless/SKILL.md.

• AWS Containers (aws-containers): Author ECS task definitions, run Fargate services, and manage App Runner deployments. Found in plugins/aws-core/skills/aws-containers/SKILL.md.

• AWS Blocks (aws-blocks): Reusable building blocks like Lambda-as-a-Service wrappers for composition. See plugins/aws-core/skills/aws-blocks/SKILL.md.

Infrastructure as Code

• AWS CloudFormation (aws-cloudformation): Validate, deploy, and troubleshoot stacks with pre-deployment scripts. Source: plugins/aws-core/skills/aws-cloudformation/SKILL.md.

• AWS CDK (aws-cdk): Migrate between CDK versions, troubleshoot synthesis, and manage bootstrap compliance. Located in plugins/aws-core/skills/aws-cdk/SKILL.md.

Observability and Operations

• AWS Observability (aws-observability): Configure CloudWatch metrics, X-Ray tracing, and Logs Insights queries. Defined in plugins/aws-core/skills/aws-observability/SKILL.md.

• AWS Messaging and Streaming (aws-messaging-and-streaming): Work with SNS, SQS, Kinesis, and EventBridge patterns. Reference: plugins/aws-core/skills/aws-messaging-and-streaming/SKILL.md.

Cost and AI Services

• AWS Billing and Cost Management (aws-billing-and-cost-management): Optimize spend with Savings Plans, Reserved Instances, and Cost Explorer analysis. Source: plugins/aws-core/skills/aws-billing-and-cost-management/SKILL.md.

• Amazon Bedrock (amazon-bedrock): Interact with Bedrock models, agents, and knowledge bases. Located in plugins/aws-core/skills/amazon-bedrock/SKILL.md.

SDK Support

• AWS SDK for Python (aws-sdk-python-usage): Boto3 patterns for pagination, waiters, and service-specific examples (S3, DynamoDB). See plugins/aws-core/skills/aws-sdk-python-usage/SKILL.md.

• AWS SDK for JavaScript v3 (aws-sdk-js-v3-usage): Modular SDK usage with SigV4a support and performance optimization. Found in plugins/aws-core/skills/aws-sdk-js-v3-usage/SKILL.md.

• AWS SDK for Swift (aws-sdk-swift-usage): Swift SDK client creation and credential handling. Source: plugins/aws-core/skills/aws-sdk-swift-usage/SKILL.md.

Skill Architecture and Key Files

Each core skill follows a consistent directory structure within plugins/aws-core/skills/. The SKILL.md file serves as the entry point, while supporting materials reside in standardized subdirectories:

• references/: In-depth markdown documentation for specific service implementations (e.g., lambda.md, s3.md).

• assets/: Helper scripts, templates, and boilerplate code (e.g., powertools-handler.py for Lambda functions).

• hooks/: Security and validation scripts such as secret-safety.py, which redacts sensitive credentials before agent transmission.

The plugin manifest at plugins/aws-core/.cursor-plugin/plugin.json exposes these skills to Cursor, while plugins/aws-core/.mcp.json configures the MCP server endpoint for agent communication.

Practical Usage: Invoking Core Skills

Agents consume core skills through natural language commands or structured skill invocations. Below are executable patterns for common workflows.

Installing the aws-core Plugin

Add the toolkit to your agent's marketplace and install the core plugin:

# Add repository to marketplace (Cursor, Kiro, etc.)

npx skills add aws/agent-toolkit-for-aws/skills

# Install the core plugin

/plugin install aws-core@claude-plugins-official

Generating Serverless Resources

Use the AWS Serverless skill to scaffold Lambda functions with proper structure:

skill aws-serverless create-lambda \
  --runtime python3.11 \
  --handler handler.handle \
  --description "Process S3 upload events"

The skill retrieves templates from aws-serverless/references/lambda.md and returns a ready-to-deploy SAM template along with a minimal handler file.

Optimizing Costs with the Billing Skill

Query cost recommendations using the AWS Billing and Cost Management skill:

skill aws-billing-and-cost-management recommend-savings \
  --service ec2 \
  --region us-east-1

This invocation reads references/service-optimization.md and returns a comparison table of Savings Plans versus Reserved Instances.

Working with AWS SDKs

Generate boto3 code with proper pagination and error handling:

skill aws-sdk-python-usage list-s3-objects \
  --bucket my-data-bucket \
  --prefix logs/

The skill generates Python code based on references/s3.md, ensuring correct pagination patterns and exception handling.

Configuring Amazon Bedrock

Provision Bedrock models with the necessary IAM policies:

skill amazon-bedrock create-model \
  --model-id anthropic.claude-v2 \
  --instance-type ml.g5.xlarge

The skill produces the IAM policy, runtime configuration, and sample invocation scripts from references/sdk-converse-api-python.md.

Security Controls and Secret Handling

The aws-core plugin implements safety guardrails through plugins/aws-core/hooks/secret-safety.py. This hook automatically redacts AWS credentials and sensitive tokens before they are transmitted back to the agent, ensuring that authentication materials never leak into chat logs or model contexts.

Summary

• The AWS Agent Toolkit delivers 15 core skills via the aws-core plugin, each defined in plugins/aws-core/skills/<skill-name>/SKILL.md.

• Skills cover authentication, serverless, containers, infrastructure as code, observability, cost optimization, and SDK usage across Python, JavaScript, and Swift.

• Each skill packages reference documentation (references/) and reusable assets (assets/) for comprehensive guidance.

• Security is enforced through pre-transmission hooks like secret-safety.py that prevent credential leakage.

• Agents invoke skills through natural language commands, receiving vetted code templates and deployment configurations.

Frequently Asked Questions

How do I install the aws-core plugin in my coding agent?

Install the plugin by adding the repository to your agent's marketplace with npx skills add aws/agent-toolkit-for-aws/skills, then run /plugin install aws-core@claude-plugins-official. The plugin manifest at plugins/aws-core/.cursor-plugin/plugin.json handles the rest of the configuration.

What file format defines a core skill?

Each core skill is defined by a SKILL.md file located in its respective directory under plugins/aws-core/skills/. This markdown file contains the skill description, procedural instructions, and references to supporting documentation in the references/ subdirectory.

How do core skills handle AWS authentication?

The Signing‑in to AWS skill manages credential configuration and MCP server sessions. Additionally, the hooks/secret-safety.py script automatically redacts sensitive credentials before they are returned to the agent, preventing accidental exposure of access keys or tokens.

Can I use core skills with any AI coding agent?

Yes, the aws-core plugin is designed for compatibility with multiple agents including Claude Code, Codex, Cursor, and Kiro. The MCP server configuration in plugins/aws-core/.mcp.json standardizes the interface, allowing any MCP-compliant client to load and invoke the skills.

{
  "mcpServers": {
    "instagit": {
      "command": "npx",
      "args": ["-y", "instagit@latest"]
    }
  }
}