Best agent frameworks for Java

Java framework for distributed, long-running agents with typed event streams, permission gating, middleware and subagents.

• 6.1K GitHub stars
• Active in the last 30 days
• Open source (Apache-2.0)

★ 6.1KLast active Oct 24, 2026

Java runtime for AI agents that streams tokens and tool events over WebSocket, SSE or gRPC, with human approvals.

• 3.8K GitHub stars
• Active in the last 30 days
• Open source (Apache-2.0)

★ 3.8KLast active Oct 23, 2026

Multi-language SDKs for embedding the GitHub Copilot agent runtime, with planning, tool calls and file edits, in your apps.

• 10.6K GitHub stars
• Active in the last 30 days
• Open source (MIT)

★ 10.6K↓ 1.2M/wkLast active Oct 24, 2026

Open-source toolkit for building, evaluating and deploying agents in Python, TypeScript, Go, Java and Kotlin, tuned for Gemini but model-agnostic.

• 22K GitHub stars
• Most weekly downloads here (2.4M)
• Active in the last 30 days

★ 22K↓ 2.4M/wkLast active Oct 24, 2026

Java library with one API over LLM providers and vector stores, plus tools, RAG and integrations for Quarkus and Spring Boot.

• 13.3K GitHub stars
• Active in the last 30 days
• Open source (Apache-2.0)

★ 13.3KLast active Oct 23, 2026

Java framework for agentic, workflow and multi-agent AI apps, with graph workflows, MCP and A2A support.

• 11.1K GitHub stars
• Active in the last 30 days
• Open source (Apache-2.0)

★ 11.1KLast active Oct 7, 2026

Java application framework from the Spring project with portable chat and embedding APIs, tool calling and vector stores.

• 9.6K GitHub stars
• Active in the last 30 days
• Open source (Apache-2.0)

★ 9.6KLast active Oct 23, 2026

Kotlin and Java framework for AI agents with tools, graph workflows, MCP, streaming and multiplatform targets.

• 4.6K GitHub stars
• Active in the last 30 days
• Open source (Apache-2.0)

★ 4.6KLast active Oct 13, 2026

JVM framework for agentic flows that plan toward goals, mixing LLM calls with code and domain models, usable from Kotlin or Java.

• 4.5K GitHub stars
• Active in the last 30 days
• Open source (Apache-2.0)

★ 4.5KLast active Oct 24, 2026

Java library for stateful, multi-agent LLM applications built as cyclical graphs, designed to work with langchain4j and Spring AI.

• 2.1K GitHub stars
• Active in the last 30 days
• Open source (MIT)

★ 2.1KLast active Oct 18, 2026

Model-agnostic SDK for building agents and multi-agent systems in Python, .NET and Java; Microsoft names Agent Framework as its successor.

• Most GitHub stars here (28,694)
• Active in the last 30 days
• Open source (MIT)

★ 28.7K↓ 77.5K/wkLast active Oct 23, 2026

Code-first Java toolkit for building and testing AI agents, with multi-agent hierarchies, a dev UI and Maven packages.

• 1.8K GitHub stars
• Active in the last 30 days
• Open source (Apache-2.0)

★ 1.8KLast active Oct 23, 2026

Quarkus extensions that connect LangChain4j to Quarkus apps, with declarative AI services and LLM, tool and embedding support.

• Active in the last 30 days
• Open source (Apache-2.0)
• For Java

★ 326Last active Oct 23, 2026

Java SDK for calling LLMs such as OpenAI, Azure OpenAI and Hugging Face, with plugins that chain functions and planners.

• Active in the last 30 days
• Open source (MIT)
• For Java

★ 276Last active Oct 23, 2026

SDK for building durable, responsive services, including agentic AI services, that cluster automatically and deploy to any infrastructure.

• Active in the last 30 days
• For Java

★ 30Last active Oct 23, 2026