Supersede older widget instances changedconnectors/building/mcp-apps/instance-supersession
Nearest release: v2.1.283, published under an hour after upstream edited the page. Shown because the two are within 24 hours of each other. Nothing here says the release caused the edit.
Upstream edited this page at 25 Sep 2026 18:00 UTC, give or take a minute or two: the time comes from Anthropic’s own sitemap rather than from a commit. This site recorded the change at 23 Oct 2026 18:07 UTC.
Upstream edited
Recorded here
Lines+2added
Lines−2removed
From line
239
where the diff opens
First seen
14 Aug 2026
this site's first read of the page
Recorded edits4to this page, all time
The whole hunk
from line 239, old and new numbered
/
from line 239
239239
240240## Next steps
241241
242* [Set `ui.domain` for Claude](/docs/connectors/building/mcp-apps/getting-started#set-ui-domain-for-claude): how to compute `_meta.ui.domain` for Claude
243* [Troubleshoot MCP Apps](/docs/connectors/building/mcp-apps/troubleshooting.md): developer tools and fixes when a widget doesn't render
242* [Set `ui.domain` for Claude](https://claude.com/docs/connectors/building/mcp-apps/getting-started#set-ui-domain-for-claude): how to compute `_meta.ui.domain` for Claude
243* [Troubleshoot MCP Apps](https://claude.com/docs/connectors/building/mcp-apps/troubleshooting.md): developer tools and fixes when a widget doesn't render
244244* [SDK API reference](https://modelcontextprotocol.github.io/ext-apps/api/index.html): `registerAppTool`, `App`, and `McpUiResourceMeta`
245245
No line in this hunk matches that.