design-doc-new

name	design-doc-new
description	Create a technical design doc / RFC in a project's docs/ from the design-doc template. Use when the user wants to write, draft, or start a design doc, RFC, technical design, tech spec, or engineering proposal for how to build something — "RFC" and "design doc" mean the same artifact here. Pass the title and/or its project as args (e.g. "Idempotent retries for payments-platform").

Create a technical design doc (a.k.a. RFC) as a project-local doc. This is the engineering how — distinct from a PRD (the product what/why) and heavier than an ADR (which records a single decision). A design doc often produces ADRs; capture those with /decision.

Read paths.projects (default 03-projects) and owner.slug from .agents/config.yaml.

1. Resolve the parent project. A design doc belongs to a project. If args names a project (or one obviously applies from context), use it — validate the slug exists as a folder in {paths.projects}/. If none is stated, ask which project this design is for; if the project doesn't exist yet, offer to run project-new first.
2. Determine the design title from args (the system/feature being designed) and generate a slug from it (lowercase, hyphen-separated, max 6 words).
3. Read _templates/design-doc.md.
4. Choose the filename: {paths.projects}/{project-slug}/docs/design-doc.md if the project has no design doc yet; otherwise {paths.projects}/{project-slug}/docs/design-doc-{feature-slug}.md. Create the docs/ folder if it doesn't exist.
5. Write the file from the template with frontmatter filled:
   • title: from args
   • slug: the feature slug
   • status: draft
   • owner: {{owner_slug}} resolved from config
   • projects: the parent project slug (a human pointer to the parent, not a rollup key — the doc already lives inside the project folder)
   • leave reviewers, jira_epic, target_date, supersedes, tags as prompts/empty
   • Keep the section structure as prompts to fill.
6. If a PRD already exists in the same docs/ (prd.md), reference it in the Appendix so the what/why and the how cross-link.
7. Add - [ ] Draft design doc: {title} #follow-up #project/{project-slug} to the current week's active file in 01-weekly/.

Output the created file path and the parent project. Note that the design doc lives in the project's docs/ (browsable there), and that decisions resolved in it should be recorded as ADRs via /decision linked with projects: [{project-slug}].