Kiro Agent Tool

The Kiro Agent tool provides integration with Kiro CLI through the MCP (Model Context Protocol) server. This tool enables AI agents to leverage Kiro's capabilities for AWS-focused code analysis, generation, and assistance.

Overview

Kiro is an AI coding assistant that provides code completions, explanations, and solutions with deep knowledge of AWS services and best practices. The Kiro Agent tool allows MCP clients to interact with Kiro CLI commands programmatically, enabling automated code assistance workflows.

Configuration

Requirements

• The kiro-cli command must be installed and available in PATH (installation guide)
• AWS credentials must be configured
• Kiro must be authenticated

Environment Variables

• ENABLE_ADDITIONAL_TOOLS: Must include kiro-agent to enable the tool
• AGENT_TIMEOUT: (optional) Timeout for Kiro operations in seconds (default: 300)
• AGENT_MAX_RESPONSE_SIZE: (optional) Maximum response size in bytes (default: 2MB)
• AGENT_PERMISSIONS_MODE: (optional) Controls whether yolo-mode parameter is exposed and its default behaviour. Options: yolo (force yolo-mode on, hide parameter), disabled/false (force yolo-mode off, hide parameter). If unset, agent can control yolo-mode via parameter. This controls the --trust-all-tools flag.

Security

The tool is disabled by default for security reasons. It must be explicitly enabled by setting:

export ENABLE_ADDITIONAL_TOOLS="kiro-agent"

Usage

Basic Parameters

• prompt (required): The instruction or question for Kiro
• resume (optional): Continue previous conversation from current directory
• agent (optional): Context profile to use for the conversation
• override-model (optional): Specify which Claude model to use
• yolo-mode (optional): Trust all tools without confirmation
• trust-tools (optional): Comma-separated list of specific tools to trust
• verbose (optional): Enable detailed logging

Examples

Basic Code Analysis

{
  "name": "kiro-agent",
  "arguments": {
    "prompt": "Review this Lambda function for security best practices and suggest improvements"
  }
}

Continue Previous Conversation

{
  "name": "kiro-agent",
  "arguments": {
    "prompt": "Now implement the caching mechanism we discussed",
    "resume": true
  }
}

Specify Model and Enable Tools

{
  "name": "kiro-agent",
  "arguments": {
    "prompt": "Help me troubleshoot this CloudFormation template",
    "yolo-mode": true,
    "verbose": true
  }
}

Features

Session Management

• Directory-based conversation history
• Resume conversations using the resume parameter
• Context preserved per working directory

Model Selection

• Support for multiple Claude models
• Default uses Kiro's current default model
• Override with specific model versions

Tool Integration

• Automatic tool approval with yolo-mode
• Selective tool trust with trust-tools
• Enhanced security with explicit enablement requirement

Response Management

• Configurable response size limits
• Intelligent truncation at line boundaries
• Timeout handling with partial output preservation

Common Use Cases

AWS Development

• CloudFormation template analysis and debugging
• Lambda function optimization and security review
• AWS CLI command generation and troubleshooting
• Infrastructure as Code best practices guidance

Code Review and Analysis

• Security vulnerability identification
• Performance optimization suggestions
• AWS service integration recommendations
• Code quality improvements

Debugging and Troubleshooting

• AWS service configuration issues
• Permission and IAM policy problems
• Network connectivity debugging
• Resource quota and limit issues

Error Handling

Common Error Scenarios

Tool Not Enabled

Error: Kiro agent tool is not enabled. Set ENABLE_ADDITIONAL_TOOLS environment variable to include 'kiro-agent'

CLI Not Found

Error: Kiro CLI not found. Please install kiro-cli and ensure it's available in your PATH

Authentication Issues

Error: Kiro authentication failed. Please ensure kiro-cli is configured properly

Tool Approval Required

Error: Tool approval required but --no-interactive was specified. Use yolo-mode parameter to automatically approve tools

Performance Considerations

Timeouts

• Default timeout: 300 seconds (5 minutes)
• Configurable via AGENT_TIMEOUT environment variable
• Operations exceeding timeout return partial output with notification

Response Size Limits

• Default limit: 2MB
• Configurable via AGENT_MAX_RESPONSE_SIZE environment variable
• Large responses are truncated at line boundaries with size information

Resource Usage

• Stateless operation - no persistent connections
• Temporary files cleaned up automatically
• Memory usage scales with response size

Security Considerations

Access Control

• Explicit enablement required via environment variable
• No pre-flight CLI installation verification
• User responsible for AWS credential management

Command Safety

• Uses exec.CommandContext with separate arguments (no shell interpretation)
• Input validation prevents command injection
• Always includes --no-interactive flag to prevent hanging

Data Handling

• No sensitive data logging in stdio mode
• Response size limits prevent memory exhaustion
• Timeout handling prevents resource locks

Troubleshooting

Installation Issues

1. Install Kiro CLI: see Kiro CLI Installation Guide
2. Verify Kiro CLI installation: which kiro-cli
3. Check AWS CLI configuration: aws configure list
4. Test Kiro authentication status

Permission Problems

1. Ensure ENABLE_ADDITIONAL_TOOLS includes kiro-agent
2. Check working directory permissions for .kiro session files
3. Verify AWS credentials and permissions

Performance Issues

1. Adjust AGENT_TIMEOUT for longer operations
2. Increase AGENT_MAX_RESPONSE_SIZE for large outputs
3. Use trust-tools or yolo-mode to avoid approval prompts

Tool Integration Problems

1. Enable verbose mode for detailed logging
2. Check tool compatibility with Kiro version
3. Use explicit tool trust configuration

Comparison with Other Agents

Feature	Kiro	Q Developer	Claude Agent	Gemini Agent
Focus	AWS/Cloud	AWS/Cloud	General Purpose	General Purpose
File Context	No @ syntax	No @ syntax	@ syntax supported	@ syntax supported
Models	Claude only	Claude only	Claude models	Gemini models
Session Management	Directory-based	Directory-based	Session ID based	Include files
Tool Trust	Granular control	Granular control	All or nothing	All or nothing

Related Documentation

• Kiro CLI Documentation
• AWS CLI Configuration
• MCP DevTools Documentation