I use custom script to store extra information for each task. The following script called note just create a markdown file named by task uuid:

#!/bin/env bash

NOTE_DIR=${HOME}/.task/notes
mkdir -p notes/
if [[ $# -eq 1 ]]; then
  uuid=$(task _get $1.uuid)
  note="${NOTE_DIR}/${uuid}.md"
  vim $note || exit 1
  task ${uuid} mod note:$(date --iso-8601=seconds) >/dev/null
else
  vim ${NOTE_DIR}/buffer
fi

And then just set UDA and alias into taskrc:

uda.note.type=date
uda.note.label=Note
alias.note=execute "${HOME}/.task/hooks/note"

Now you can take a note with vim for each task if necessary:
task note 1
And you may also filter them by UDA:
task note.isnt:
And of course, the best way to manage markdown in vim is vimwiki!

An alternative is taskopen