write-planning-brieflisted

# Write Planning Brief Write a durable source document from the current planning conversation and any supplied decision, research, prototype, or design artifacts. Do not interview the user and do not implement or create plan tasks. When information is missing, preserve the gap and mark the brief `More decisions required` rather than inventing an answer. ## Source and output Accept an optional topic, source paths, and output path. Verify repository-state claims against disk and reference authoritative artifacts by path or URL instead of duplicating them. Choose the output path in this order: 1. a path supplied by the caller; 2. the repository's established decision/planning-document convention; 3. `plans/decisions/<topic-slug>.md` when `plans/` exists; 4. `docs/planning/<topic-slug>.md` otherwise. Create parent directories when needed. If a brief for the same topic already exists, update that file after reading it; do not create competing sources of truth. Never overwrite a different topic. ## Distillation rule Capture every durable requirement, decision, constraint, non-goal, evidence pointer, and unresolved checkpoint needed by a fresh planner. Do not copy the transcript, exploratory chatter, temporary misunderstandings, raw research output, or repository search output. Preserve an important rejected alternative only when its rationale prevents a future agent from reopening or reversing a material decision accidentally. Distinguish verified facts, user decisions, re