feat(ui): support prefersBorder option for MCP Apps by aharvard · Pull Request #6465 · block/goose

aharvard · 2026-01-13T14:26:13Z

Summary

Adds support for the _meta.ui.prefersBorder option in MCP App resources. When an MCP App returns prefersBorder: false in its resource metadata, the UI wrapper border and rounded corners are removed, allowing the app to render edge-to-edge.

Changes

Read prefersBorder from _meta.ui in the resource response (defaults to true)
Conditionally apply border/rounded styling based on this preference
Refactored resource state into a single ResourceData object for cleaner code

Usage

MCP Apps can now specify border preference in their resource response:

{
  "uri": "ui://widget/example.html",
  "mimeType": "text/html;profile=mcp-app",
  "_meta": {
    "ui": {
      "prefersBorder": false
    }
  },
  "text": "<!doctype html>..."
}

Before / After

Before	After

Before: MCP App with default border and rounded corners
After: MCP App with prefersBorder: false - no wrapper border

Copilot

Pull request overview

This PR adds support for the prefersBorder option in MCP App resource metadata, allowing apps to control whether they render with or without a UI wrapper border.

Changes:

Introduced ResourceData interface to consolidate resource state (html, csp, prefersBorder)
Read prefersBorder from _meta.ui in resource responses with proper fallback to true
Conditionally apply border and rounded corner styling based on preference

DOsinga · 2026-01-13T14:45:13Z

ui/desktop/src/components/McpApps/McpAppRenderer.tsx

  }

-  if (!resourceHtml) {
+  if (!resource.html) {


consider unifying the effective two arms of the if now that the payload is growing, i.e.

const toRender = resource.html ? <iframe> : "Loading MCP app..."

aharvard · 2026-01-13T15:48:59Z

ui/desktop/src/components/McpApps/McpAppRenderer.tsx

+        resource.prefersBorder ? 'border border-borderSubtle rounded-lg' : 'my-6'
+      )}
+    >
+      {resource.html && proxyUrl ? (


@DOsinga PTAL

I unified resource.html and proxyUrl as we don't need a discrete state for proxyUrl loading

Also, leaving this inline instead of extracting as a const. I noticed a hard-to-reproduce issue where the iframe ref might have gotten lost or something... the rendered mcp app would be sitting there w/ no messages being sent down. Maybe a closure issue? Not sure. But I think what I got works.

* main: (41 commits) Allow customizing the new line keybinding in the CLI (#5956) Ask for permission in the CLI (#6475) docs: add Ralph Loop tutorial for multi-model iterative development (#6455) Remove gitignore fallback from gooseignore docs (#6480) fix: clean up result recording for code mode (#6343) fix(code_execution): handle model quirks with tool calls (#6352) feat(ui): support prefersBorder option for MCP Apps (#6465) fixed line breaks (#6459) Use Intl.NumberFormat for token formatting in SessionsInsights (#6466) feat(ui): format large and small token counts for readability (#6449) fix: apply subrecipes when using slash commands (#6460) Fix: exclude platform_schedule_tool in CLI (#6442) Fix: Small update in how ML-based prompt injection determines final result (#6439) docs: remove SSE transport and rename to Streamable HTTP (#6319) fix: correct Cloudinary extension command and env variable (#6453) fix: add gap between buttons in MacDesktopInstallButtons.js (#6452) refactor: include hidden dotfiles folders in file picker search (#6315) upgraded safe npm packages (#6450) chore(deps): bump react-router and react-router-dom in /ui/desktop (#6408) chore(deps): bump lru from 0.12.5 to 0.16.3 (#6379) ...

* main: fix: require auth when running goose on non loopback address (#6478) chore(deps): bump hono from 4.11.3 to 4.11.4 in /ui/desktop (#6485) feat(cli): graceful fallback for keyring failures (#5808) fix: support global .gooseignore and negation patterns (#6157) docs: manual config for jetbrains (#6490) fix: Recipe slash command doesn't work with single optional parameter (#6235) fix(openrouter): Handle Gemini thoughtSignature for tool calls (#6370) docs: fix extensions page (#6484) Allow customizing the new line keybinding in the CLI (#5956) Ask for permission in the CLI (#6475) docs: add Ralph Loop tutorial for multi-model iterative development (#6455) Remove gitignore fallback from gooseignore docs (#6480) fix: clean up result recording for code mode (#6343) fix(code_execution): handle model quirks with tool calls (#6352) feat(ui): support prefersBorder option for MCP Apps (#6465) fixed line breaks (#6459) Use Intl.NumberFormat for token formatting in SessionsInsights (#6466) feat(ui): format large and small token counts for readability (#6449) fix: apply subrecipes when using slash commands (#6460)

…ased * 'main' of github.com:block/goose: fix(code_execution): serialize record_result output as JSON (#6495) perf(google): avoid accumulating thoughtSignatures across conversation history (#6462) fix(openai): make tool_call arguments optional and fix silent stream termination (#6309) fix: Improve error messages for invalid tool calls (#6483) fix: require auth when running goose on non loopback address (#6478) chore(deps): bump hono from 4.11.3 to 4.11.4 in /ui/desktop (#6485) feat(cli): graceful fallback for keyring failures (#5808) fix: support global .gooseignore and negation patterns (#6157) docs: manual config for jetbrains (#6490) fix: Recipe slash command doesn't work with single optional parameter (#6235) fix(openrouter): Handle Gemini thoughtSignature for tool calls (#6370) docs: fix extensions page (#6484) Allow customizing the new line keybinding in the CLI (#5956) Ask for permission in the CLI (#6475) docs: add Ralph Loop tutorial for multi-model iterative development (#6455) Remove gitignore fallback from gooseignore docs (#6480) fix: clean up result recording for code mode (#6343) fix(code_execution): handle model quirks with tool calls (#6352) feat(ui): support prefersBorder option for MCP Apps (#6465) fixed line breaks (#6459)

Signed-off-by: fbalicchia <fbalicchia@cuebiq.com>

feat(ui): support prefersBorder option for MCP Apps

e01ce64

Copilot AI review requested due to automatic review settings January 13, 2026 14:26

aharvard marked this pull request as draft January 13, 2026 14:27

Copilot started reviewing on behalf of aharvard January 13, 2026 14:28 View session

Copilot AI reviewed Jan 13, 2026

View reviewed changes

refine styles

d8de8f7

aharvard marked this pull request as ready for review January 13, 2026 14:37

DOsinga approved these changes Jan 13, 2026

View reviewed changes

refactor(McpAppRenderer): improve loading state handling and styling

00e41b6

aharvard commented Jan 13, 2026

View reviewed changes

aharvard merged commit 1a2bc48 into main Jan 13, 2026
24 of 25 checks passed

aharvard deleted the mcp-app-prefers-border branch January 13, 2026 17:17

github-actions bot mentioned this pull request Jan 22, 2026

chore(release): release version 1.21.0 (minor) #6634

Merged

fbalicchia pushed a commit to fbalicchia/goose that referenced this pull request Jan 23, 2026

feat(ui): support prefersBorder option for MCP Apps (block#6465)

89ca609

Signed-off-by: fbalicchia <fbalicchia@cuebiq.com>

raj-subhankar pushed a commit to raj-subhankar/goose that referenced this pull request Feb 14, 2026

feat(ui): support prefersBorder option for MCP Apps (block#6465)

23e7c26

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feat(ui): support prefersBorder option for MCP Apps#6465

feat(ui): support prefersBorder option for MCP Apps#6465
aharvard merged 3 commits intomainfrom
mcp-app-prefers-border

aharvard commented Jan 13, 2026 •

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aharvard commented Jan 13, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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Summary

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aharvard Jan 13, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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aharvard commented Jan 13, 2026 •

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aharvard Jan 13, 2026 •

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