Grilling: lock MVP knobs and Phase 2+ Non-goals list

[cursor]

Part of #300

Blocked by: #302

Question

Lock the remaining MVP knobs vs Phase 2+ / Non-goals list for the Spec: at least MaxDegreeOfParallelism (or equivalent), RunAsync return shape (void vs minimal result/trace), empty/single-node/diamond edge-case depth in Spec prose, and any other knobs surfaced by #302 boundaries research.

Already locked on the map (do not reopen): fail-fast only; no DI/Autofac; no typed edges; no sync path; document-level TContext concurrency contract; request-prep Sample sketch.

[Skymly]

Resolution — Grilling: lock MVP knobs and Phase 2+ Non-goals list

Did not reopen map-locked items: fail-fast only; no DI/Autofac; no typed edges; no sync in MVP; document-level TContext concurrency contract; request-prep Sample sketch.

MVP knobs

• MaxDegreeOfParallelism / run options: Phase 2+ — MVP same-wave uses natural concurrency (e.g. full WhenAll-style); no Dop surface in MVP.
• RunAsync return: ValueTask only (no WorkGraphTrace / observer in MVP).
• Spec edge-case depth (required acceptance lines):
  • Empty graph → illegal (Build / Create Error; exact exception type left to Runtime PR).
  • Single-node → legal; RunAsync runs that step.
  • Diamond (A→C, B→C) → legal; C after both predecessors.

Non-goals (Spec must state domain is not / does not specify)

1. Channel Pipeline (watch list): typed TIn/TOut edges, Channel<T> stage wiring — scope boundary, not an admission.
2. Extending or impersonating Composite TraverseParallel* (tree levels ≠ DAG waves).
3. TPL Dataflow alternative / wrapper / actor mailbox (consuming Task/ValueTask is fine).
4. Sync Execute path.
5. Aggregate / continue-on-error failure modes.
6. DI / Autofac.
7. TContext isolate/merge framework.
8. Unregistered-step Analyzer (per Grilling: lock MVP Work Graph diagnostic matrix #304).

Phase 2+ (same domain, later — not refused forever)

1. Dop / WorkGraphRunOptions (or equivalent).
2. RunAsync trace / observer.
3. Sync path (still Phase 2+, not elevated to permanent Non-goals).
4. Aggregate / continue failure modes.
5. DI registration.
6. Unregistered-step Analyzer.

Phrasing

Use peer Spec style (#256 / #287): name watch-list domains in Out of Scope without specifying them; prefer #302 option-set combined checklist as author menu (A–F), with this resolution as the locked selection.

[Skymly]

Resolved: MVP knobs and Non-goals/Phase 2+ list locked; see resolution comment.