[Feature]: Filter task list by milestone in CLI and MCP #546
Description
milestone_list exists and milestones are stored in task frontmatter, but there’s no way to filter tasks by milestone. The CLI task list supports --status, --assignee, --parent, and --priority, but not milestone. The MCP task_list tool has the same limitation and rejects a milestone parameter with "Unknown field 'milestone' is not allowed."
Right now the only option is to grep task files for milestone: m-X. That works, but it’s brittle and doesn’t fit the rest of the tooling. Adding a --milestone (or -m) flag to backlog task list and a milestone parameter to the MCP task_list tool would make milestone filtering consistent with the other filters.
I find Milestones useful, in theory, for marking "these features belong to x.x release", but without filtering natively in the tool, finding which tasks belong to what milestone requires using the WebUI. You can't even filter by the milestones in the TUI.
(As a side note having status/priority filtering be by pressing cursor up/down and labels be a modal menu, is just weird design in TUI.)