Atmosphere
Real-time AI agent runtime for the JVM that runs one agent class on Spring AI, LangChain4j and other backends with streaming, MCP, A2A and AG-UI.
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About Atmosphere
Atmosphere is listed in our frameworks category and is aimed at builders. Real-time AI agent runtime for the JVM that runs one agent class on Spring AI, LangChain4j and other backends with streaming, MCP, A2A and AG-UI. Pricing, as the maker states it: Open source. Maturity: Active. We last checked the official link on 2026-10-18.
Atmosphere at a glance
- Category: Frameworks
- Built for: Developers and teams building with AI agents
- Pricing: Open source (as the maker states it)
- Licence: Apache License 2.0 (OSI-approved open source)
- GitHub: Atmosphere/atmosphere · 3,821 stars (as of Oct 21, 2026)
- Latest release: js-v5.0.51, Oct 17, 2026
- Last commit: Oct 21, 2026
- Official site: async-io.live
- Listed on AgentScout: Oct 18, 2026
Atmosphere FAQ
What is Atmosphere?
Real-time AI agent runtime for the JVM that runs one agent class on Spring AI, LangChain4j and other backends with streaming, MCP, A2A and AG-UI.
How much does Atmosphere cost?
Atmosphere's pricing, as the maker states it: Open source. Open-source tools are free to use, though you may still pay for model API usage or a hosted plan. Check the official site for current plans.
Is Atmosphere open source?
Yes. Atmosphere's GitHub repository is published under the Apache License 2.0, according to the licence file in the repo.
Where can I find Atmosphere's source code?
On GitHub at Atmosphere/atmosphere, which had 3,821 stars as of Oct 21, 2026. The latest release is js-v5.0.51 (Oct 17, 2026).
What are alternatives to Atmosphere?
Similar tools include fast-agent, assistant-ui, OpenUI, LangGraph4j, Embabel and AG-UI.
Facts from our link-checked listing, the GitHub repository and the official site. See something wrong? Suggest an edit.
Atmosphere ratings and reviews
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Atmosphere alternatives
Other frameworks tools in our directory. See all frameworks tools →
fast-agent
Framework to build, run and evaluate agents with strong MCP, ACP and A2A support.
assistant-ui
Open-source React components and runtimes for building AI chat and agent front ends with streaming, tools and persistence.
OpenUI
Framework-agnostic generative UI framework with a compact streaming language and runtimes for React, Vue, Svelte and Angular.
LangGraph4j
Java library for building stateful multi-agent applications as graphs, working with LangChain4j and Spring AI.
Embabel
Agent framework for the JVM from the creator of Spring.
AG-UI
Agent-User Interaction protocol for streaming agent state and events into frontend apps.
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