A plain text UI that returns an HTTP status of 422, indicating that the request was well-formed, but semantically incorrect.
Examples
default_ui()
#> Warning: No ui specified for this request. Loading default ui.
#> $status
#> [1] 422
#>
#> $content_type
#> [1] "text/plain"
#>
#> $content
#> [1] "422: Unprocessable Entity. The conditions necessary to choose a UI were not met."
#>
#> $headers
#> $headers$`X-UA-Compatible`
#> [1] "IE=edge,chrome=1"
#>
#>
#> attr(,"class")
#> [1] "httpResponse"