Eight fields. Three of them determine whether GTD actually works for you or becomes another abandoned productivity system after three weeks.
Where Context Collapses
The failure mode in every GTD implementation is the same: tasks accumulate without enough context to act on them. "Call Marcus about the project" sits in the inbox for four days because "the project" isn't specified, you don't know which area of responsibility it belongs to, and you can't tell whether it's a five-minute call or a thirty-minute decision requiring preparation. The system holds the task but not the information needed to complete it.
Area and Project are the two fields that restore context without overhead. Area of responsibility is the life domain — Work/Operations, Work/Strategy, Personal Finance, Health, Household — or whatever maps to how you actually divide your commitments. Project is the specific initiative within that area. "Refinance home loan" is a project under Personal Finance. "Marketing campaign Q2" is a project under Work/Strategy. Tasks that aren't attached to a project live directly under their Area.
The combination means filtering by Area during a weekly review shows everything you're responsible for across a domain. Filtering by Project shows only the open tasks on a specific initiative. That's the two-level view that makes a large task database navigable without constant manual scanning.
Time Cost Changes How You Work a List
Time Cost in minutes is the field that makes opportunistic execution possible. Standard GTD theory says context (where you are and what tools you have) determines what to work on in a given window. Time cost adds the third dimension: how long do you actually have?
A 15-minute gap between calls doesn't fit a task you estimated at 45 minutes. It fits three tasks estimated at 5 minutes each, or one at 12 minutes with a small buffer. Without time estimates, you scan the list, make a rough judgment, pick something, and often misjudge — starting something you can't finish, which is worse than waiting.
Priority H/M/L is the triage layer. Filter by High priority and time cost under 20 minutes during a constrained window and you have an actionable sub-list pulled from a potentially overwhelming backlog in seconds. That filtered view is the difference between productive motion and decision paralysis.
Next Due is not the same as a deadline. It's the date by which the task should be in motion — the commitment date for the next action. Tasks with no due date drift. A task with a next due date anchors to a specific day in your review cycle and shows up in a filtered date view when the date arrives.
Done as a boolean closes the loop. Toggling it removes the task from active filters without deleting the record — you retain the history of completed actions, which matters for reconstructing what was done on a project and for performance reviews that require a summary of accomplishments.