Theia AI – Open-Source AI Harness Platform for Tools and IDEs

Design custom AI interactions with flexible chat interfaces, inline suggestions, or entirely custom UI elements that integrate seamlessly into your tool environment.
👉 Beyond AI Chat Agents with Theia AI
Create domain-specific AI agents with specialized knowledge that can interact natively with your tool components and support multi-turn comunication flows.
👉 Introducing Interactive AI Flows
Connect to any AI model of your choice—cloud-based services, self-hosted solutions, or fully local LLMs. Balance capabilities, response time, costs and be ready for the models of tomorrow.
👉 Why Theia supports any LLM!
Integrate AI seamlessly with your tool ecosystem with full control over APIs, databases, and services while determining exactly what data is shared with AI services.
👉 Enhancing Your Tools with Chat Context
Get professional support from experienced Theia contributors and committers specializing in AI-native development.
Build AI agents customized for your domain's knowledge and workflows with ready components for function calling, context retrieval, multi-turn conversations, custom UX elements and integration with external AI components.
Move beyond one-shot responses with AI agents that engage users in dynamic, multi-step interactions, presenting actionable options and guiding through complex workflows.
Provide agents with relevant context using advanced retrieval techniques. Optionally, users can scope requests by dragging files, symbols, or domain-specific elements into the chat.
Keep AI-proposed changes organized through structured Change Sets that separate suggestions from conversation, enabling users to systematically review complex modifications.
Extend AI capabilities beyond simple chat views into specialized tool components, providing contextual suggestions directly where users work.
Leverage dynamic templates, flexible variable management, variants, reusable fragments, and runtime modifications for rapid development iterations and user customization.
Learn more about prompt management in the Theia IDE →
Integrate external tools and context sources via MCP, and extend your agents with Agent Skills and Plugins. Theia AI tracks the agent ecosystem as it evolves, so your tool picks up emerging agent standards without you having to build them yourself.
Learn more about MCP support →
Example for integraing Theia AI, Git and MCP →
Experience Theia AI live in action. The AI-powered Theia IDE, built on Theia AI is an open source development environment that puts the power of AI in your hands—with full transparency and control. Theia IDE gives you complete visibility and flexibility over your AI interactions.
Theia AI is part of the powerful Theia platform that allows you to tailor every aspect of your tool to your individual needs. Efficiently develop and deliver Cloud & Desktop IDEs and tools with modern web technologies and join the open source and vendor neutral ecosystem of successful tool builders in the Theia ecosystem.
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