The update_tasks tool does not expose Asana’s due_at field (the timed due date). It only exposes due_on (date-only). As a result, there is no way to set a time-of-day due date on an existing task through the connector. Writes that pass due_at are silently dropped — the call returns success-shaped output with no change applied.
Exact symptom observed
Calling update_tasks with a due_at value returns:
{ “data”: [], “failed”: [], “summary”: “Updated 0 of 1 tasks.” }
Neither data (succeeded) nor failed is populated, and a follow-up get_task confirms due_at is unchanged. The unknown field is ignored rather than rejected, so there is no error surfaced to the caller.
Control test on the same task, same tool, a supported field:
// update_tasks with { “task”: “”, “name”: “” }
{ “data”: [{ “gid”: “”, “name”: “…” }], “failed”: [], “summary”: “Updated 1 of 1 tasks.” }
This proves the task is writable and the permissions/state are fine — the issue is specific to the due_at field on update_tasks.
Can support for updating due_at field be added to MCP Server v2?