How the host is currently displaying the view. "inline" until the host reports otherwise.
Host capabilities negotiated at initialization. undefined until the bridge has connected.
The host context object exactly as the host reported it, with none of the
fallbacks the fields above apply. Use it to read host-specific fields this
handle does not surface. undefined until the host first reports context.
Host identity (name and version). undefined until the bridge has connected.
Whether the MCP Apps bridge is connected. While false, every field holds its documented fallback.
User locale (BCP 47). Falls back to "en-US" when the host does not report one.
Vertical layout budget in pixels: the most height the view can occupy.
Derived from the host's container dimensions. When the host fixes the
container to an exact height, that height is reported; otherwise the
host's stated maximum is. undefined when the host reports no layout
constraint — treat that as unbounded. The raw dimensions remain available
on hostContext.containerDimensions.
Horizontal layout budget in pixels: the most width the view can occupy.
Same derivation as maxHeight: an exact container width when the host
fixes one, otherwise the host's stated maximum, otherwise undefined
(unbounded).
Host-reported platform. "mobile" on mobile hosts; otherwise "web".
Inspector maps Desktop → "web" and Mobile → "mobile".
Mobile safe area insets in pixels. All zeros when the host reports none.
Host color theme. "light" until the host reports a theme.
User timezone (IANA). Falls back to the browser's timezone, then "UTC".
Host application user-agent string. Falls back to the browser's own user agent.
Host environment and bridge availability for the current view.