architecture

Files (3)

• SKILL.md
• codex-prompt.md · references/
• template.md · references/

SKILL.md (first lines)

# Architecture Design Skill

## Trigger

- Keywords: architecture, architecture design, architecture doc, component diagram, 3-architecture, system design, document architecture

## When NOT to Use

- Tech spec writing (use `/tech-spec`)
- Code implementation (use `/feature-dev`)
- Architecture consulting only (use `/codex-architect`)
- Implementation roadmap (use `/deep-analyze`)

## Usage

```bash
/architecture                          # Auto-detect feature, create/update
/architecture <feature-keyword>        # Specify feature
/architecture --skip-debate            # Skip Phase 3 adversarial debate
```

## Workflow

```mermaid
sequenceDiagram
    participant U as User
    participant C as Claude
    participant E as Explore Agent
    participant X as Codex
    participant D as Architecture Designer
    participant B as /codex-brainstorm

    C->>C: Phase 0: Context Resolution
    par Phase 1: Research
        C->>E: Track A: Code pattern analysis (background)
        C->>C: Track B: Read tech-spec (inline)
    end
    E-->>C: Component list + dependencies
    C->>X: Track C: Architecture advice
    X-->>C: Independent recommendations
    C->>D: Phase 2: Architecture Design
    D-->>C: Component + flow + decisions
    C->>B: Phase 3: Verification (debate)
    B-->>C: Equilibrium conclusion
    C->>C: Phase 4: Write 3-architecture.md
    C->>U: Auto-trigger /codex-review-doc
```

## Phase 0: Context Resolution

Detect the target feature using the 5-level cascade.

See `@skills/create-request/references/feature-context-resolution.md` for the full algorithm.

```bash
# The wrapper, not the CLI directly: it owns the failure payload, so the full shape with
# `scan_error: true` arrives however the CLI fails — nonzero exit, signal, partial write, or a
# payload that is not the agreed shape. (Not when `node` itself is unavailable: nothing running
# under node survives that.) `|| echo '{}'` would produce a payload the gate cannot see as failure.
node scripts/resolve-feature.js
```

> **`scan_error` gate.** Gate on **`scan_error !== false`**, not on `scan_error === true`. When it
> is not exactly `false` the four source sets are **unknown, not empty** — the corpus could not be
> enumerated (unreadable directory, broken taxonomy, no repository), *or* the resolver never ran
> and a shell fallback supplied a payload with no such field at all. `{}` is the shape that made
> the stricter test useless: it has no `scan_error`, so `=== true` is false and the gate passes a
> payload that contains nothing. Do not proceed as though the feature has no authority documents —
> report and take the ⚠️ Need Human exit. A `key` may still be present, so a non-null `key` is not
> evidence the sets are complete.

| State | Mode |
|-------|------|
| `3-architecture.md` exists | Update (incremental) |
| `3-architecture.md` absent + a tech spec resolves | Create (tech-spec-informed) |
| `3-architecture.md` absent + no tech spec resolves | Create (code-only research) |
| Feature not resolved | Gate: Need Human |

"A tech spec resolves" means `design_records` holds an entry of `type: tech-spec` — the same
resolution Track B uses.

**`design_records` is an array, and more than one entry can be a tech spec**, so "the entry" needs a
rule rather than an assumption. `docs/features/auto-loop-evolution/` is the live case: a split spec
contributes `2-tech-spec/2-tech-spec.md` **and** its sub-document `2-tech-spec/1-phase-d-hook-hardening.md`,
both `type: tech-spec` design records. Select in this order, and stop at the first that answers:

**Filter first, then choose — every later rule reads the filtered list, never the whole set.**
Candidates are the `design_records` entries whose `type` is `tech-spec`; a requirements or
architecture record is not a candidate at any step, and a rule phrased over "entries" rather than
over candidates will select one. `docs/features/codex-review-spec/` and
`docs/features/harness-engineering-rebrand/` are the live proof: neither has a tech-spec design
record, each has exactly one canonical requirements record, and a canonicality test applied to the
unfiltered set picks it.

| # | Candidates (`design_records` where `type: tech-spec`) | Result |
|---|---------------------------------------------------|--------|
| 1 | none | **No tech spec resolves** — the ordinary code-only row of the table above. Not an exit: a feature that has not been specced is a normal state, and Track C is given `(none — do not read a spec)` |
| 2 | exactly one | that one |
| 3 | two or more, exactly one with `is_canonical: true` | that one — a split spec's main file keeps the canonical filename, which is what makes it the main file |
| 4 | two or more, and none or several canonical | **Gate: Need Human**, naming the candidates |

Rows 1 and 4 are different answers and must not be collapsed: "there is no spec" is a fact the skill
acts on, "there are two and I cannot tell which" is an ambiguity it must not resolve by picking. **The set decides, and the set also names the file.** `canonical_docs` is
role-blind: it selects the tech spec from `doc_inventory` whatever role that document resolves to,
so a spec that has declared itself `History record` or `Work record` is still non-null there while
being absent from `design_records`. Reading the alias as evidence of design authority is exactly the
confusion the source sets replace — and it is no better as a *path* selector: it is chosen across
the whole inventory by type and canonicality, so a historical canonical `2-tech-spec.md` beside a
design-record variant `2-tech-spec-v2.md` makes the set and the alias name different files. Take
both the decision and the path from the `design_records` entry's own `file`; do not rejoin through
the alias for either. Testing for the literal filename
`2-tech-spec.md` would read a split spec (`2-tech-spec/2-tech-spec.md`) or a variant
(`2-tech-spec-v2.md`) as "no tech spec" and silently drop to code-only mode.

### Scope Gate

For small features (tech-spec WBS has only 1 task, or no tech-spec and < 3 related files), suggest keeping architecture in tech-spec Section 3 instead of creating a separate document. Use AskUserQuestion to confirm.

## Phase 1: Architecture Research (parallel)

From sd0xdev/sd0x-harness, MIT.

More from sd0xdev/sd0x-harness