Hosted
Challenge your assistant
You play X, the assistant plays O, and both of you move on the same board inside the conversation. It is the reference saga a2ui game: four MCP tools, no account, and a game kept for 24 hours under an unguessable identifier.
Where it works
| Host | Status | Evidence |
|---|---|---|
| Claude web | Verified in recorded runs | A game was played to a nine-move draw through the direct connector, and the marketplace plugin was added and used on the web. The first card sometimes needed the host’s Retry button. Claude Code and Claude Desktop were not checked. Source for Claude web |
| ChatGPT web | Verified in recorded runs | A game was played to a nine-move draw through a custom MCP server. A card sometimes needed one Try again. This is manual custom-MCP setup, not a directory listing. Source for ChatGPT web |
| Alexa+ | Not verified | No Alexa+ run of this game is recorded, so nothing here claims it works there. Source for Alexa+ |
Connect in your assistant
Endpoint: https://examples.saga-ai.dev/tic-tac-toe/mcp
What you need
- An assistant that can add a custom MCP connection on the web: Claude (Customize → Connectors) or ChatGPT (Plugins → Add custom MCP server).
- No account or sign-in for the game itself. A managed workspace may need an administrator to allow custom connections.
- Nothing to install or build for the hosted game.
Claude on the web: add the marketplace plugin
- Open Customize → Plugins → Add plugin → Add marketplace → Add from a repository.
- Enter MachineWisdomAI/saga-a2ui-examples and choose Sync.
- Install saga-tic-tac-toe. It adds the endpoint below and a short skill.
- Start a new chat and ask Claude to play tic-tac-toe. In Claude Code the equivalent commands are /plugin marketplace add MachineWisdomAI/saga-a2ui-examples and /plugin install saga-tic-tac-toe@saga-a2ui-examples; the owner checked the web path only.
Claude on the web: add the connector directly
- Open Customize → Connectors → Add custom connector.
- Name it saga Tic Tac Toe, paste the endpoint below and choose No sign-in when offered.
- Connect it, enable it from the connectors menu in a new chat, and ask Claude to start a game.
ChatGPT on the web: add a custom MCP server
- Open Plugins → + → Add custom MCP server.
- Name it saga Tic Tac Toe, paste the endpoint below and choose No authentication.
- Add and connect it, select it in a new chat and ask to start a game.
Endpoint check
- Status
- Verified
- Checked on
- Result
- Read-only probe: initialize succeeded (server saga-tic-tac-toe, MCP 2025-06-18); tool discovery listed new_game, show_game, get_game and play_move; both board views were listed and read as MCP App HTML; the four icon files were served. No game tool was run.