Property Type Defaulting to List

What I’m trying to do

I’d like the type in the below template to create a text type in front matter.
It seems to default to list. Is there a way to change this?

Things I have tried

<%*
  let title = tp.file.title
  if (title.startsWith("Untitled")) {
    title = await tp.system.prompt("Title");
    await tp.file.rename(title);
  } 
  
  tR += "---"
%>
created: <%tp.file.creation_date()%>
type: 
up: []
related: []
alias: 
tags:
---
# <%* tR += title %>
---
<% tp.file.cursor(0) %>

With a quick test, created and type were a text type; up and related were a list type using the above template. Try removing the brackets for those. e.g.

<%*
  let title = tp.file.title
  if (title.startsWith("Untitled")) {
    title = await tp.system.prompt("Title");
    await tp.file.rename(title);
  } 
  
  tR += "---"
%>
created: <%tp.file.creation_date()%>
type: 
up: 
related: 
alias: 
tags:
---
# <%* tR += title %>
---
<% tp.file.cursor(0) %>

Running this gives me a list type for the first four Properties.

Using your example precisely (square brackets removed), does make list types.

The exceptions being:
created: gets converted to a date format
alias: defaults to alias type
tags: defaults to tag type

What I’m looking for is how to have one default to text (rather than list).