Rota Brainstorm

---
name: rota-brainstorm
description: Use when a Major feature or P0 bug needs design negotiation before implementation planning, or on "brainstorm 42", "design this item".
---

# rota-brainstorm — Per-item Design

Sits between `/rota-capture` (what) and `/rota-plan` (how). Scope is one backlog item (`#N`; file backend `B07`/`F03`/`T05`); project-level exploration is `/rota-vision`. The design (`rota design show <ID>`) is soft input to `/rota-plan`, never required. Milestone tags are context only.

Copy this checklist and track your progress:
```
- [ ] Step 1 — Resolve target
- [ ] Step 2 — Load context
- [ ] Step 3 — One draft
- [ ] Step 4 — One approval
- [ ] Step 5 — Store
```

## Step 1 — Resolve target

Target: `#N` / bare number (issue backend) or `[BFT]\d{2,}` (file backend), plus optional `--grill` (Step 3). Reject milestone and slice IDs: *"/rota-brainstorm operates on a single backlog item. For project-level exploration use /rota-vision; for slice planning use /rota-plan."* `rota item field get <ID> --name title` exits 3 for an unknown item: refuse and point at `/rota-capture`.

If a design exists, ask once (View / Edit / Replace, default View): View runs `rota design show <ID>` and exits; Edit loads it as the starting draft; Replace runs `rota design rm <ID>` first.

## Step 2 — Load context

Follow `references/context-load-protocol.md` (parallel, silent), plus `rota item show <ID>` for state and comments (`decision` comments bind; `references/issue-mode.md`, "Resuming an item") or the file backend's detail file, and `rota glossary read <term>`. DECISIONS matches are hard boundaries: on a conflict, surface it before drafting.

**`## Acceptance` already in the issue body?** Treat it as settled; Step 3 covers approaches only. Otherwise draft it in Step 3.

## Step 3 — One draft

**Grill first, once.** Run one pass of `references/grilling.md` before drafting when the item is a Major feature or P0 bug, or the invocation has `--grill`. Skip it when the issue body already has `## Acceptance` (`--grill` does not override). For other items ask nothing unless real ambiguity or a decision conflict remains after the item, its thread and the code; then ask the one question that unblocks you (`AskUserQuestion`, ≤ 4 options). Record answers that changed direction in Step 5. If a question needs code-touching evidence (feasibility, library support, performance), say: *"This warrants a spike. Run `/rota-spike <name>` first, then re-invoke `/rota-brainstorm <ID>`."* Don't guess.

Write the whole design as one unsaved markdown draft:

- **Goal**: one sentence on what shipping this means
- **Design**: 3-8 sentences: chosen shape, moving parts, where they live
- **Approaches considered**: 2-3 candidates, each with shape, pros, cons, deciding factor; mark the pick. A simple item may have one approach and a two-line design.
- **Acceptance**: a `- [ ]` checklist, observable outcomes (skip when the issue body already has one)
- **Open questions**: what must be answered before or during `/rota-plan`; mark spike candidates
- **Assumptions**: implicit constraints made explicit

Self-review before showing: no placeholders, no contradictions (pick matches Design; Open questions vs Assumptions), nothing leaking into sibling items.

## Step 4 — One approval

Ask once: **Approve and hand off to `/rota-plan`**, **Approve, no plan yet**, or **Revise** (apply redlines, show again). Silence is not approval.

## Step 5 — Store

```bash
rota design add <ID> --title "<title>"                     # mint the stub
rota design put <ID> --body-file <scratch-file>            # issue backend: publish the approved draft
```

On the issue backend the design is a note on the item's issue (`references/issue-mode.md`). On the file backend it is `.rota/designs/<ID>.md`: `Edit` the stub's sections, keep the frontmatter. Post each answer that changed direction with `rota item comment add <ID> --kind decision --body-file -`.

Report two lines (artifact, approaches, open questions). On hand-off say *"Run `/rota-plan <ID>` next."*

## Key principles

- **No noise.** Don't narrate loads or recap.
- **One draft, one approval.** The artifact is the outcome, not a transcript.
- **Single item.** Project scope is `/rota-vision`; slice scope is `/rota-plan`.

## References

- [`references/design-exploration.md`](references/design-exploration.md): shared spine with `/rota-vision`.
- [`references/grilling.md`](references/grilling.md): the grilling pass (Major / P0 / `--grill`).
- [`references/subagent-dispatch.md`](references/subagent-dispatch.md): the `light` subagent that grilling sends for broad reads.
- [`references/context-load-protocol.md`](references/context-load-protocol.md): shared parallel context load.
- [`references/knowledge-consult.md`](references/knowledge-consult.md): the K+D query pattern the load uses.