Bring your services to AI assistants and agents, including Alexa+, ChatGPT, Claude and more, with less engineering work.
saga a2ui combines robust foundations from Google's A2UI project with Machine Wisdom AI's production and safety expertise, designed to fit your existing API platform.
Meet the adopters building with saga a2ui.
Your team knows what customers should be able to do with your service. saga a2ui provides the application foundations for turning those tasks into interactive experiences, from browsing content to taking an action through an existing API. The aim is to give your team a head start and reduce the custom application code it has to maintain as these experiences evolve.
A2UI describes the interface, its data bindings and updates, independently of how messages travel between an agent and its host. Delivery can use MCP Apps or A2A (planned). saga a2ui connects the application model to rendered components, user actions and the application's lifecycle, with an MCP Apps integration. You can build on that foundation while keeping your own services, authentication and business rules.
Use TypeScript to define an interface, update it as application data changes, and bind a component to a typed action. Define actions that run locally or call your backend, with behavior expressed in code rather than embedded in the A2UI JSON. saga a2ui manages the action's connection to the view, including what happens when a result arrives after the view has changed or closed.
The action guide follows a notes application through these interactions, showing how the same application contract serves different views.
Start with a Node, Express, Fastify, Hono or Hapi backend, or add saga a2ui to an existing service. saga a2ui carries the verified request identity through to your application, where your server checks permissions and performs the operation.
Application processing, MCP integration, components and React bindings have separate packages, so you can choose the parts your application uses and review their dependencies. The package guide explains their responsibilities and how they fit together.
saga a2ui's FaithfulCard component presents Markdown in a styled card, preserving the supplied answer, including source attribution for RAG agents. It renders that answer directly, without asking the host LLM to paraphrase it for display.
Your application chooses which links may open and which image hosts are allowed. For content that needs more restrictive handling, links can remain inactive and images can wait until the reader chooses to load them. These settings let you adapt the presentation to where your content comes from and what readers should be able to do with it.
Explore a Patreon-style subscription and podcast experience using synthetic accounts and media. Browse episodes, switch accounts and try protected playback, including denied access and expired playback grants. The demo runs locally and does not connect to Patreon.
From a source checkout, with Node 22.12.0 or newer and npm:
npm ci
npm run build:demo
cd apps/lit-host/dist/demo
npm install --omit=dev
npm startOpen the Open the demo host page: address printed by the server. The demo includes its own local host, so you can explore the application without deploying it or connecting an assistant. See the podcast demo guide for its controls and setup.
For a browser walkthrough of actions and their implementation, try the interactive notes tour. It runs against a simulated server and links each explanation to the source.
Follow Getting started for a starter project or an existing-backend integration. The Lit renderer powers the demo and starter templates; the React integration provides action controls and FaithfulCard.
For Hapi, the integration map shows how to reuse the bridge in your own app, with a registration example, bridge-owned lifecycle handling and the application’s responsibilities.
The core, MCP, React and components packages are available on npm at 0.1.0-rc.1 (the source on main is at the 0.7.6-rc.1 release candidate, which is not published). They export TypeScript source for applications that use a bundler. See the React integration guide for imports and dependency configuration.
- Action guide: connect interactions to application behavior.
- Development reference: build and test the SDK.
- Candidate updates and rollback: keep installed packages and views together.
- Host compatibility: choose a host for your application.
- Blueprints: explore the architecture and component contracts.
- Building with saga a2ui: IASER's Ansari integration and how to share your application.
Younes Abouelnagah, founder of Machine Wisdom AI
Working on Headspace for Alexa+ inspired saga a2ui. Getting the production integration working took attention away from the application itself, and the player remained bespoke. I evaluated other approaches, but couldn't find one that fit our existing API platform and the dependency-review requirements we worked within. We built the integration in-house.
I wanted robust application foundations that another team could adopt within the platform it already operated. I chose A2UI for its application model and the engineering behind it, with MCP Apps providing host integration. saga a2ui brings those pieces together with the application behavior I wanted to reuse on the next project.
My perspective on content safety comes from AMP and Gmail Add-ons, alongside five years as a Principal Engineer in Roblox Trust and Safety. That experience informs how saga a2ui handles displayed content and the choices it leaves with the application developer.
Amazon's announcement of Headspace's Alexa+ integration describes the project that inspired this work.
saga a2ui is maintained by Machine Wisdom AI for its clients.
Talk to Machine Wisdom AI about bringing your services to Alexa+, ChatGPT, Claude and more, or join saga a2ui adopters by following the Quick Start guide.
We welcome fixes, reproducible bug reports, application examples and contributions to the A2UI and MCP Apps ecosystem. Open an issue or read Contributing. Report vulnerabilities through Security.
SDK code is licensed under Apache-2.0, with third-party notices for included work.