An update in case it’s helpful. I can certainly pattern match like:

<.error :for={{:email, {error_msg, _}} <- @changeset.errors}>
  <%= error_msg %>
</.error>

However, I suspect I’m still doing something wrong. The docs for phx-feedback-for seem to indicate that wrapping my error with a field value like :email would filter errors just for that field. But I have to explicitly match on :email to avoid multiple error messages appearing in one spot. It just feels a bit cumbersome or redundant, but it works.

That’s because the input component from the generated core components uses the field scoped @errors rather than the entire form’s @changeset.errors. It then uses these input field specific errors to render error components within the input component itself.

  def input(%{field: %Phoenix.HTML.FormField{} = field} = assigns) do
    assigns
    |> assign(field: nil, id: assigns.id || field.id)
    |> assign(:errors, Enum.map(field.errors, &translate_error(&1)))
    ...
  end