jukka-matti · jukka-matti · May 30, 2026 · May 30, 2026 · May 30, 2026 · May 30, 2026
diff --git a/apps/azure/src/persistence/__tests__/applyAction.test.ts b/apps/azure/src/persistence/__tests__/applyAction.test.ts
@@ -679,11 +679,15 @@ function makeMeasurementPlan(id: string, hypothesisId: string): MeasurementPlan
     createdAt: NOW,
     deletedAt: null,
     hypothesisId,
-    factor: 'X',
+    outcome: 'Y',
+    primaryFactor: 'X',
+    neededFactors: [],
     method: 'sensor',
     sampleSize: 10,
     owner: 'pm-1',
     status: 'planned',
+    scope: [],
+    processLocation: '',
   };
 }
 

diff --git a/apps/pwa/src/persistence/__tests__/applyAction.test.ts b/apps/pwa/src/persistence/__tests__/applyAction.test.ts
@@ -639,11 +639,15 @@ function makeMeasurementPlan(id: string, hypothesisId: string): MeasurementPlan
     createdAt: NOW,
     deletedAt: null,
     hypothesisId,
-    factor: 'X',
+    outcome: 'Y',
+    primaryFactor: 'X',
+    neededFactors: [],
     method: 'sensor',
     sampleSize: 10,
     owner: 'pm-1',
     status: 'planned',
+    scope: [],
+    processLocation: '',
   };
 }
 

diff --git a/docs/03-features/specifications.md b/docs/03-features/specifications.md
@@ -129,7 +129,7 @@ Both investigation starting points converge on the Wall:
 | **Data-first (exploratory)**     | Paste → explore in Analyze → notice patterns → create Findings → group into Hypotheses on the Wall.                                                                          |
 | **Hypothesis-first (deductive)** | Open Wall → create Hypothesis → add Measurement Plans (what evidence is needed) → collect out-of-product → re-paste → Findings link to Plans → Hypothesis status progresses. |
 
-Measurement Plan fields (V1): factor, method, sample size, owner, status, hypothesis link, optional linked-findings, optional MSA-required flag (informational only). Formal MSA / Gage R&R workflow + statistical sample-size calculator defer to V2.
+Measurement Plan fields (V1 DCP shape — IM-2): `primaryFactor`, `outcome`, `neededFactors[]` (dataset column names — IM-3 join contract), `scope: ConditionLeaf[]` (WHERE snapshot), `processLocation` (ProcessMap step id), `method`, `sampleSize`, `owner`, `status`, `hypothesisId` (required + immutable), optional `opDef`/`msaNote` notes (informational — not gates). `msaRequired` flag removed; formal MSA / Gage R&R workflow defers to V2. Full field reference: [Measurement Plan DCP](workflows/measurement-plan-dcp.md).
 
 ---
 

diff --git a/docs/03-features/workflows/measurement-plan-dcp.md b/docs/03-features/workflows/measurement-plan-dcp.md
@@ -0,0 +1,100 @@
+---
+tier: living
+purpose: design
+title: Measurement Plan (DCP Shape)
+audience: human
+category: workflow
+status: active
+last-reviewed: 2026-05-30
+related: [analyze-wall, adr-085, adr-087, hypothesis, process-maps]
+layer: L3
+kind: ui
+serves:
+  - docs/03-features/specifications.md
+  - docs/03-features/workflows/analyze-wall.md
+---
+
+# Measurement Plan (DCP Shape)
+
+A Measurement Plan is a sub-entity of a Hypothesis on the Investigation Wall. It specifies
+**what evidence to collect, how to collect it, under what conditions, and at which process step** —
+the DCP (Detection Control Plan) pattern adapted for investigation.
+
+Each Hypothesis can have zero or more Measurement Plans. Plans are created in-line via the
+`AddPlanForm` component, rendered as `MeasurementPlanChip` rows below each Hypothesis card on the Wall.
+
+## Field reference (spec §7.1)
+
+| Field              | Type                    | Required                 | Notes                                                                                                                                                                                                                                                                                                                                                  |
+| ------------------ | ----------------------- | ------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
+| `hypothesisId`     | `Hypothesis['id']`      | **Required + immutable** | Exclusively links the plan to one Hypothesis. Cannot be patched (excluded from `MeasurementPlanPatch` via `Omit<>`). See decision-log 2026-05-30.                                                                                                                                                                                                      |
+| `outcome`          | `string`                | Required                 | The Y being studied on this plan. Pre-filled from the project/hypothesis outcome at the call site when available; otherwise user-entered.                                                                                                                                                                                                              |
+| `primaryFactor`    | `string`                | Required                 | The primary X being measured. Renamed from `factor` (IM-2).                                                                                                                                                                                                                                                                                            |
+| `neededFactors`    | `string[]`              | Required (may be `[]`)   | **Values are dataset column names** (not display labels). Stratifiers or covariates to collect alongside `primaryFactor`. IM-3's column-overlap matcher joins on these names — preserving this contract is critical.                                                                                                                                   |
+| `sampleSize`       | `number`                | Required                 | Minimum planned sample count.                                                                                                                                                                                                                                                                                                                          |
+| `method`           | `MeasurementMethod`     | Required                 | One of: `sensor`, `manual-count`, `gemba-walk`, `expert-assessment`, `other`.                                                                                                                                                                                                                                                                          |
+| `owner`            | `ProjectMember['id']`   | Required                 | Entity id of the responsible member (Lead or Member; Sponsors are excluded from the owner picker).                                                                                                                                                                                                                                                     |
+| `status`           | `MeasurementPlanStatus` | Required                 | Lifecycle state: `planned` → `in-progress` → `complete` or `skipped`.                                                                                                                                                                                                                                                                                  |
+| `scope`            | `ConditionLeaf[]`       | Required (may be `[]`)   | A **snapshot copy** of the active WHERE drill-chip conditions at plan-creation time (ADR-085). Derived from `analysisScopeStore.categoricalFilters` via `buildConditionFromCategoricalFilters`. This is **not** a reference to the `ProblemStatementScope` entity — it is a captured point-in-time WHERE clause. Empty when no drill chips are active. |
+| `processLocation`  | `string`                | Required (may be `''`)   | ProcessMap node id (`step-${slug}-${seq}`) identifying the process step this plan targets. Resolved against canonical ProcessMap node ids (ADR-087). Empty string `''` is allowed for mapless projects — ADR-087 tolerates orphaned/empty `stepId` values pre-launch.                                                                                  |
+| `opDef`            | `string?`               | Optional                 | Free-text operational-definition note — **informational only, not a maturity gate**.                                                                                                                                                                                                                                                                   |
+| `msaNote`          | `string?`               | Optional                 | Free-text MSA / Gage R&R comment — **informational only, not a gate**. Replaces the removed `msaRequired: boolean` flag (IM-2). Formal MSA / Gage R&R workflow defers to V2.                                                                                                                                                                           |
+| `linkedFindingIds` | `Finding['id'][]?`      | Optional                 | Finding ids linked to this plan via `MEASUREMENT_PLAN_LINK_FINDING`.                                                                                                                                                                                                                                                                                   |
+
+## DCP contract notes
+
+- **`neededFactors[]` = dataset column names.** This is a hard contract: IM-3's
+  column-overlap matcher (`packages/core/src/...`) joins `neededFactors` against
+  the dataset's column keys. Do not store display labels here.
+
+- **`processLocation` join.** ProcessMap node ids are canonical (`step-${slug}-${seq}`,
+  minted by `canvasStore`). `processLocation` is an intentionally non-strict FK (ADR-087):
+  orphaned or empty values are tolerated pre-launch so the form can be submitted without
+  a configured processMap.
+
+- **`scope` is a snapshot, not a live filter.** The `ConditionLeaf[]` is captured once
+  at plan-creation time from `analysisScopeStore.categoricalFilters`. After creation the
+  plan's `scope` does not update when the drill chips change. This is intentional — the
+  scope documents the WHERE at the time the measurement commitment was made.
+
+- **`opDef` and `msaNote` are optional notes.** VariScout V1 treats these as informational
+  context that improves communication across the team. They are **not** maturity gates,
+  not required for plan status progression, and not validated against any schema beyond
+  `string`.
+
+## Persistence
+
+Plans are stored in the `measurementPlans` Dexie table (both PWA and Azure apps), indexed
+on `id`, `hypothesisId`, `status`, and `deletedAt`. The new DCP fields (`outcome`,
+`neededFactors`, `scope`, `processLocation`, `opDef`, `msaNote`) are non-indexed object
+fields — Dexie stores them freely without an IDB version bump. No migration is required
+for existing rows (wedge = no existing production rows).
+
+The reducer (`reduceMeasurementPlans` in `packages/core/src/measurementPlan/actions.ts`) is
+a pure spread-merge — it requires no changes when new fields are added to `MeasurementPlan`
+(the `MeasurementPlanPatch` type auto-widens via `Partial<Omit<...>>`).
+
+## UI threading
+
+```
+WallCanvas (planningProps bag)
+  └─ derives stepOptions from processMap via deriveProcessSteps()
+  └─ forwards defaultScope? + defaultOutcome? from planningProps
+     └─ HypothesisCardWithPlans
+          └─ AddPlanForm
+               scope = defaultScope ?? []
+               processLocation = selected stepOption.id ('' if none / no options)
+               outcome = user input || defaultOutcome || ''
+```
+
+Call sites that cannot cheaply source `defaultScope` or `defaultOutcome` pass `undefined`;
+the form defaults to `[]` / `''` respectively.
+
+## Related decisions
+
+- [ADR-085](../../07-decisions/adr-085-drop-question-problem-statement-scope.md) — `ConditionLeaf`
+  scope capture (WHERE snapshot).
+- [ADR-087](../../07-decisions/adr-087-process-step-model-reconciliation.md) — `processLocation`
+  non-strict join; `deriveProcessSteps` as the single read source.
+- [Decision log 2026-05-30](../../decision-log.md) — `hypothesisId` stays required + immutable;
+  `neededFactors[]` = dataset column names contract pinned.
diff --git a/docs/decision-log.md b/docs/decision-log.md
@@ -28,6 +28,8 @@ When in doubt: capture, don't invent. Record the decision; link to its source ar
 
 Decisions we keep relitigating. Each entry: short statement, rationale, closing artifact, date pinned.
 
+- **2026-05-30 — IM-2: `MeasurementPlan.hypothesisId` stays required + immutable; `neededFactors[]` = dataset column names contract.** `decision`: Spec §11 open-Q #2 resolved. `hypothesisId` is kept required on `MeasurementPlan` (no "bare condition" plan without a Hypothesis); it is excluded from `MeasurementPlanPatch` via `Omit<>` (type-level enforcement). No plan-creation path exists without a Hypothesis, so the weaker "optional at creation, set later" design adds complexity for zero V1 benefit. `neededFactors: string[]` values are **dataset column names** (not display labels) — IM-3's column-overlap matcher joins on these keys. Changing to display labels would silently break the IM-3 join. Related: [measurement-plan-dcp L3 doc](03-features/workflows/measurement-plan-dcp.md), spec §7.1, ADR-085, ADR-087. _Pinned 2026-05-30._
+
 - **2026-05-30 — IM-1 shipped (PR #249); CoScout `legacy.ts` retirement (complete ADR-068) scheduled as a Wave-1 PR, must precede IM-3.** `decision`: IM-1 (drop `Question` entity + `ProblemStatementScope` first-class) merged as an atomic cascade (core/stores/hooks/ui/apps/data/i18n + residual cleanup + 6-package test layer), preceded by Bucket-2 pre-existing-fix PR #245 for a green baseline. Its adversarial review surfaced that `packages/core/src/ai/prompts/coScout/legacy.ts` (1647 lines, the pre-ADR-068 monolith) is a **stalled deprecation**: `buildCoScoutSystemPrompt`/`buildCoScoutMessages` have ZERO production callers (live path is `assembleCoScoutPrompt` via `tools/registry.ts`), but the dead code is kept alive by backward-compat tests (`promptTemplates.test.ts`/`promptSafety.test.ts`), forcing dual-maintenance + duplicated tool defs (IM-1 paid the tax: stale Question prompt copy + a registry/legacy split that turned a 3-line tool removal into a multi-file reconciliation). **Decision:** complete the ADR-068 migration as a dedicated Wave-1 PR (disjoint `coScout/` subtree — no conflict with IM-2/5/7/0b-2): relocate the still-live utils (`formatKnowledgeContext` ×7 callers; audit `buildCoScoutInput`/`buildCoScoutTools`) into the modular tree, move any genuine prompt-safety contract coverage onto `assembleCoScoutPrompt`, then delete the dead monolith + its backward-compat tests. **Must land before IM-3** (auto-link is CoScout-adjacent). Why: a stalled deprecation (dead code pinned by its own tests + a duplicated source of truth) costs more than completing the migration, and doing it before the CoScout-touching wave PRs avoids re-paying the tax. Build-state + tracked deferrals: [[investigation-surface-build]]; IM-1 follow-ups in [`ephemeral/investigations.md`](ephemeral/investigations.md). Related: [adr-068](07-decisions/adr-068-coscout-cognitive-redesign.md), [[investigation-model-design]]. _Pinned 2026-05-30._
 
 - **2026-05-29 — Investigation-model design graduated → spec + 5 ADRs + master plan; four review calls locked.** `new spec` + `new ADR`: promoted the 2026-05-29 Clusters A/B/C investigation-model design from a decision-log candidate to [`superpowers/specs/2026-05-29-investigation-surface-design.md`](superpowers/specs/2026-05-29-investigation-surface-design.md) + ADRs [085](07-decisions/adr-085-drop-question-problem-statement-scope.md)–[089](07-decisions/adr-089-retire-mode-lens-user-axis.md) + [master plan](superpowers/plans/2026-05-29-investigation-surface-master-plan.md) (IM-0a…IM-7). Grounded against source via 8 grounding agents (refined the design: three step homes not two; `ProblemCondition`/`ScopeFilter` name-collisions → new `ProblemStatementScope`; the What-If chain already exists; 8f LOD ≠ factor-family coarsening; no `SuspectedCause` type — `stores/CLAUDE.md` stale; `isPaidTier` fully deleted). Initial commit `04854150`; investigations.md entry marked `[PROMOTED 2026-05-29]`.

diff --git a/packages/core/src/measurementPlan/__tests__/actions.test.ts b/packages/core/src/measurementPlan/__tests__/actions.test.ts
@@ -7,11 +7,15 @@ const basePlan: MeasurementPlan = {
   createdAt: 100,
   deletedAt: null,
   hypothesisId: 'h-1',
-  factor: 'Nozzle temperature',
+  outcome: 'Fill Weight',
+  primaryFactor: 'Nozzle temperature',
+  neededFactors: [],
   method: 'sensor',
   sampleSize: 50,
   owner: 'pm-1',
   status: 'planned',
+  scope: [],
+  processLocation: '',
 };
 
 describe('reduceMeasurementPlans — MEASUREMENT_PLAN_ADD', () => {
@@ -45,7 +49,7 @@ describe('reduceMeasurementPlans — MEASUREMENT_PLAN_UPDATE', () => {
   });
 
   it('leaves non-matching plans unchanged', () => {
-    const otherPlan: MeasurementPlan = { ...basePlan, id: 'mp-2', factor: 'Other' };
+    const otherPlan: MeasurementPlan = { ...basePlan, id: 'mp-2', primaryFactor: 'Other' };
     const next = reduceMeasurementPlans([basePlan, otherPlan], {
       kind: 'MEASUREMENT_PLAN_UPDATE',
       planId: 'mp-1',
@@ -65,7 +69,7 @@ describe('reduceMeasurementPlans — MEASUREMENT_PLAN_REMOVE', () => {
     expect(next).toHaveLength(1);
     expect(next[0].deletedAt).toBe(200);
     expect(next[0].id).toBe('mp-1');
-    expect(next[0].factor).toBe(basePlan.factor);
+    expect(next[0].primaryFactor).toBe(basePlan.primaryFactor);
   });
 
   it('does not mutate input', () => {
@@ -120,7 +124,8 @@ describe('MeasurementPlanPatch', () => {
     const _patch3: MeasurementPlanPatch = { deletedAt: 999 };
     // @ts-expect-error hypothesisId in Omit list
     const _patch4: MeasurementPlanPatch = { hypothesisId: 'h-other' };
-    // Allowed: status, factor, sampleSize, owner, method, linkedFindingIds, msaRequired
+    // Allowed: status, primaryFactor, outcome, neededFactors, sampleSize, owner, method,
+    //          scope, processLocation, opDef, msaNote, linkedFindingIds
     const _patch5: MeasurementPlanPatch = { status: 'complete', sampleSize: 100 };
     expect(true).toBe(true);
   });