Google ADK (Ruby)

Ruby implementation of Google's Agent Development Kit for building AI agents.

⚠️ DISCLAIMER: This is an UNOFFICIAL Ruby port of Google's Agent Development Kit (ADK). This gem is not affiliated with, endorsed by, or maintained by Google. It is a community-driven implementation based on the public Python ADK repository. Use at your own risk.

Google ADK (Agent Development Kit) is a Ruby gem that provides a flexible framework for building, orchestrating, and deploying AI agents. It's a port of Google's Python ADK, bringing the same powerful agent capabilities to the Ruby ecosystem.

• Multiple Agent Types: LLM agents, sequential, parallel, and loop workflow agents
• Tool Integration: Easy integration of custom tools and functions
• Event-Driven Architecture: Stream events for real-time agent interactions
• Session Management: Built-in session and state management
• Flexible Orchestration: Run agents individually or compose them into complex workflows
• Plugin System: Extend functionality with custom plugins

Add this line to your application's Gemfile:

gem 'google-adk'

And then execute:

bundle install

Or install it yourself as:

gem install google-adk

require 'google-adk'

# Create an agent
agent = Google::ADK::LlmAgent.new(
  name: 'assistant',
  model: 'gemini-2.0-flash',
  instructions: 'You are a helpful assistant'
)

# Run with a runner
runner = Google::ADK::InMemoryRunner.new(
  agent: agent,
  app_name: 'my_app'
)

# Execute and stream events
runner.run(user_id: 'user123', message: 'Hello!') do |event|
  puts "[#{event.author}]: #{event.content}" if event.content
end

# Define a custom tool
calculator = Google::ADK::FunctionTool.new(
  name: 'calculator',
  description: 'Performs calculations',
  callable: proc { |expression:| eval(expression) }
)

# Create agent with tools
agent = Google::ADK::LlmAgent.new(
  name: 'math_assistant',
  model: 'gemini-2.0-flash',
  instructions: 'You help with math problems',
  tools: [calculator]
)

# Sequential workflow
research_agent = Google::ADK::LlmAgent.new(name: 'researcher', model: 'gemini-2.0-flash')
writer_agent = Google::ADK::LlmAgent.new(name: 'writer', model: 'gemini-2.0-flash')

sequential = Google::ADK::SequentialAgent.new(
  name: 'report_builder',
  agents: [research_agent, writer_agent]
)

# Parallel execution
parallel = Google::ADK::ParallelAgent.new(
  name: 'multi_analyzer',
  agents: [agent1, agent2, agent3],
  aggregation_strategy: :all
)

# Loop execution
loop_agent = Google::ADK::LoopAgent.new(
  name: 'refiner',
  agent: refiner_agent,
  max_iterations: 3
)

Agents are the fundamental building blocks:

• BaseAgent: Abstract base class for all agents
• LlmAgent: Language model-powered agent for conversations
• SequentialAgent: Executes sub-agents in sequence
• ParallelAgent: Executes sub-agents in parallel
• LoopAgent: Executes an agent in a loop

All agent interactions produce events that flow through the system:

event = Google::ADK::Event.new(
  invocation_id: 'inv-123',
  author: 'assistant',
  content: 'Hello! How can I help?'
)

Context manages conversation state and agent lifecycle:

context = Google::ADK::InvocationContext.new(
  session: session,
  agent: agent,
  invocation_id: 'inv-123',
  session_service: service
)

Sessions persist conversation history and state:

service = Google::ADK::InMemorySessionService.new
session = service.create_session(
  app_name: 'my_app',
  user_id: 'user123'
)

See the examples/ directory for more comprehensive examples:

• basic_agent.rb - Simple agent creation and usage
• multi_agent_system.rb - Complex multi-agent workflows
• tool_usage.rb - Custom tools and agent-as-tool patterns

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests.

# Run tests
bundle exec rake spec

# Run linter
bundle exec rubocop

# Build gem
bundle exec rake build

Bug reports and pull requests are welcome on GitHub at https://github.com/yourusername/google-adk-ruby

The gem is available as open source under the terms of the MIT License.