Google Agent Development Kit

Google Agent Development Kit (ADK) is an open-source framework for building, evaluating and deploying AI agents. It suits developers who want to shape agent behavior in code across multiple languages and environments. Its breadth is a strength, though Agent Config’s narrower model and language support matters if you plan to use that feature.

Overview

ADK combines deterministic code with adaptive AI reasoning in graph-based workflows, and lets agents delegate work through a hierarchy of specialized agents. That makes it a flexible foundation for applications that need structured control as well as model-driven decisions, rather than a single conversational flow.

The framework supports Gemini, adapters for other model providers and locally running models. Its integrations catalog spans MCP, Google Cloud, databases, search, observability and third-party services. Model choice is therefore broader than Gemini alone, but Agent Config currently works only with Gemini and requires Python—a meaningful constraint for teams using other models or languages.

Key features

ADK provides tools to build, debug and evaluate agents, including multi-turn evaluation datasets and local evaluation through the CLI or development UI. That gives developers a way to assess behavior as conversations unfold, not just at a single prompt.

Agents can stream text and audio bidirectionally, and ADK manages session context while offering integration points for longer-term memory services. Deployment options include Google Cloud Agent Runtime, Cloud Run, GKE and container-friendly infrastructure, including local Docker or Podman environments. The range supports development locally and deployment across several environments, though cloud or model usage may bring separate access requirements or billing.

Security guidance addresses identity and authorization, input and output guardrails, sandboxed code execution and network controls. These are useful areas to account for when building agents, but guidance is not a substitute for configuring and operating the safeguards in a deployment.

Pricing

Google Agent Development Kit (ADK): free. The open-source framework is free, with no paid ADK tier described. That suits developers who want the framework without a license charge; it does not make model or cloud services free, as those may require separate access or billing.

Platforms

ADK supports API, Linux, macOS, Windows, web and self-hosted environments. It is available in Python, TypeScript, Go, Java and Kotlin, with installation instructions for all five languages. That breadth is useful for teams working across different stacks, although Agent Config remains limited to Python and Gemini.

Who it's for

ADK is a strong fit for developers building agents that need custom workflows, delegation, evaluation, voice streaming or deployment beyond a single hosted environment. Its multiple language options and model adapters suit teams that want to integrate agents into existing software systems.

It is less suitable for teams seeking a model-agnostic Agent Config experience or a turnkey managed service: that configuration feature is Gemini-only and Python-only, while ADK itself is a framework to build and deploy with. Community resources are linked, but Google and the ADK team do not support content in external community resources.

Pros and cons

• Pro: Five supported languages and adapters for external and local models give developers room to fit ADK to different stacks and model choices.
• Pro: Graph workflows, hierarchical delegation and multi-turn evaluation tools support more involved agent systems than a single-step interaction.
• Pro: Local containers and several Google Cloud deployment targets allow teams to choose where to run agents.
• Con: Agent Config is restricted to Gemini and Python, limiting its usefulness for teams standardizing on other models or languages.
• Con: Free framework access does not cover potential model or cloud service costs, so total operating expense depends on the services used.
• Con: External community resources do not carry support from Google or the ADK team.

Alternatives

For a broader comparison, browse AI Agent Platforms.

Choose Camunda if you want a freemium option with a free self-managed development plan for local development and testing, plus a free trial. Choose Workato Agentic if its Free plan’s 50,000 one-time credits suit your needs, or if you want its listed Pro plan at $75 a month.

Flowise is worth considering if a free hosted-style allowance of two flows and assistants, 100 predictions per month and 5MB storage fits your project. UiPath Agentic Automation offers free basic development and attended automation capabilities, with Community available at no cost subject to eligibility under its Community Agreement.

Relevance AI may suit a small web-based workload: its Free plan includes 100 credits per day, one user and 10MB of knowledge. Langflow is another free option with API, web and self-hosted platform support.

Consider StackAI if its free allowance of 500 runs per month, two projects and one seat is a closer match. Dify offers a free Sandbox with 200 message credits, one workspace member and five apps, among other caps.

Verdict

Choose ADK if you want a free, code-oriented framework for building agents across languages, models and deployment environments. Its combination of workflow control, delegation and evaluation is the main reason to choose it; look elsewhere if you need Agent Config to work beyond Gemini and Python, or want model and cloud costs bundled into a fixed framework price.