/architectural-decisions

name: architectural-decisions
description: >
  Use when encountering questions about WHY code is built a certain way, when about to make
  architectural changes (new patterns, restructuring, choosing between approaches), or when
  the user asks about design rationale in a Repowise-indexed codebase (.repowise/ directory exists).
  Also activates when commit messages or code comments contain decision signals like "WHY:",
  "DECISION:", "TRADEOFF:", "ADR:".
user-invocable: false

Architectural Decisions with Repowise

Repowise captures architectural decisions — the *why* behind how code is built.

`get_why` has four modes — pick by what you pass:

1. `get_why(query="why is auth using JWT?")` — keyword + semantic decision search. 2. `get_why(query="src/auth/service.py")` — decisions governing that file, plus its origin story and an alignment score (does the file still follow its own ADRs?). 3. `get_why(query="why was caching added?", targets=["src/auth/cache.py"])` — target-anchored search; decisions touching the targets get boosted. 4. `get_why()` — the decision-health dashboard.

Decisions are mined from five sources (ADR files, PR and squash-commit bodies, inline markers, git archaeology, and centrality-bounded code comments). Each rationale traces to a verbatim source span, stamped exact / fuzzy / unverified. When no decision exists for a path, `get_why` falls back to git archaeology so the call is never empty.

When the user asks "why is X built this way?"

Call `get_why(query="X")`.

When about to make an architectural change

1. Call `get_why(query="the specific area you're changing")` to find existing decisions that govern that area. 2. If decisions are found, present them to the user before proceeding — they may not want to contradict an existing architectural choice. 3. If no decisions are found, proceed but note that no recorded decision governs this area.

When called with no specific query

Call `get_why()` with no arguments to get the decision-health dashboard:

• Stale decisions that may no longer apply
• Proposed decisions awaiting confirmation
• Ungoverned hotspots (high-churn files with no recorded decisions)

The same signals surface in the CLI via `repowise decision health` / `/repowise:decision`, and you can query *why* mid-task with `repowise why` / `/repowise:why` (the `get_why` adapter). Review auto-proposed decisions with `repowise decision confirm`.

When a file has decision markers

If you see `# WHY:`, `# DECISION:`, `# TRADEOFF:`, or `# ADR:` comments in code, call `get_context(targets=["that_file.py"])` to see the full decision record with context and affected modules.

Recording new decisions

If the user makes an architectural decision during the conversation, suggest: "Want to record this decision? Add a `# DECISION:` comment in the relevant code, or run `repowise decision add` to capture it formally."