diff --git a/docs/spec-driven-countries.md b/docs/spec-driven-countries.md
index 6d438af0..f34d2394 100644
--- a/docs/spec-driven-countries.md
+++ b/docs/spec-driven-countries.md
@@ -212,37 +212,57 @@ artifact label, range values such as `0_17` and `65_plus` become `0–17` and
 A geography-role dimension sets `row.geography` and uses its declared `level`
 or `"region"`. Other dimensions become `target_dimensions` with `key`,
 `label`, `value`, `source_key`, `raw_value`, and an optional zero-based `rank`.
+The published dimension ID, not its display label, determines `key`. Simple
+lowercase IDs retain keys such as `bd_age_band`; IDs containing other
+characters receive a lossless query-safe encoding. Consequently, two distinct
+dimensions may share a display label without merging into one facet.
 Facet values use rank order only when every displayed value has a rank;
 otherwise the legacy facet sorter remains in force. Structured rows are also
 excluded from whole-population estimate-scope inference.
 
-Adapter selection is per row and never by country:
+### Target representation classification
 
-1. A plain-object `targets[].dimensions` selects `structured`, even when the
-   dictionary is absent or the row object is empty.
-2. Otherwise, a filter matched by the shared filter-decomposition specs selects
-   `legacy_filter`.
-3. Every other row selects `legacy_name`, preserving dotted/slash name parsing
-   and Chronicle metadata dimensions.
+The dashboard classifies each target row by structure before normalizing it,
+then summarizes the complete `targets` array. Diagnostics schema versions do
+not identify the target representation: published schema 5 and schema 6 files
+can both contain legacy string fields. The structural classification is:
 
-Each target response records this choice as `dimension_adapter`. Calibration
-summary and target-diagnostics responses include:
+1. `structured` when every row has a plain-object `source` with a non-empty
+   `id`, a plain-object `variable` with a non-empty `id`, and a plain-object
+   `dimensions` field. Use `{}` when a target has no dimensions.
+2. `legacy` when no row has object-valued `source`, `variable`, or `dimensions`
+   fields.
+3. `mixed` when complete structured rows and complete legacy rows occur together.
+4. `unknown` when there are no target rows.
+
+Every target row must independently satisfy either the structured or legacy
+shape. Partially structured rows are invalid. In a mixed file, each complete
+structured row uses the structured reader and each complete legacy row uses the
+legacy reader; the file-level `mixed` value is descriptive and does not select a
+third normalization strategy.
+
+Calibration summary and target-diagnostics responses report the classification:
 
 ```json
 {
   "target_schema": {
     "diagnostics_schema_version": 7,
-    "structured_dimensions": true
+    "structured_dimensions": true,
+    "target_representation": "structured"
   }
 }
 ```
 
 `structured_dimensions` reports whether the diagnostics published a plain
-dimension dictionary; it does not choose every row's adapter.
+dimension dictionary. `target_representation` summarizes the collection. The
+existing per-row `dimension_adapter` response field remains for compatibility
+and describes only whether that row's dimensions came from a structured object,
+a known legacy filter, or legacy name and metadata parsing.
 
 ### Structured source and variable identifiers
 
-Targets accept their legacy strings or the following objects:
+Fully structured targets use the following objects together. The `dimensions`
+object is required and may be empty:
 
 ```json
 {
@@ -258,34 +278,38 @@ Targets accept their legacy strings or the following objects:
         "id": "population",
         "label": "Resident population",
         "measure": "count"
-      }
+      },
+      "dimensions": {}
     }
   ]
 }
 ```
 
-Publisher-key precedence is Chronicle metadata, then `source.id`, then legacy
-name grammar. `source_citation` is the legacy source string or
-`source.citation`; `source_url` is the structured URL or `null`. The publisher
-label precedence is the manifest map, `source.label`, then the shared
-humanizer.
-
-Variable-ID precedence is `variable.id`, `metadata.variable`, then the existing
-artifact/name fallbacks. A structured ID remains an identifier; its display
-name is separately returned as `variable_label`. Measure precedence is
-`variable.measure`, then the existing first-dimension and Chronicle metadata
-logic. Legacy string sources and variables retain their existing values,
-families, citations, facets, and grouping. The new response fields are
-additive: `source_label`, `source_url`, `variable_label`, and
-`dimension_adapter`.
+For a `structured` file, navigation identity comes only from `source`,
+`variable`, and `dimensions`. Legacy names, filters, registry families, and
+Chronicle metadata cannot change its source, statistic, geography, or
+breakdown dimensions. The source and variable IDs remain stable selection
+keys; their labels are returned separately for display.
+
+For a `legacy` file, the isolated legacy reader handles the established dotted,
+slash, Chronicle metadata, and known filter encodings. It does not interpret an
+arbitrary underscore as a structural separator.
+
+For a `mixed` file, fully legacy rows retain legacy behavior. Partially
+structured rows use the compatibility precedence: Chronicle publisher ID,
+then `source.id`, then legacy source parsing; `variable.id`, then legacy
+variable parsing; structured dimensions, then known filter dimensions, then
+legacy metadata and name dimensions. This prevents one partially migrated row
+from changing unrelated legacy rows in the same file.
 
 ### Producer follow-up
 
 Microcosm release producers must publish all of the following before the legacy
-presentation and parsing adapters can be retired:
+presentation and normalization readers can be retired:
 
 - `release_manifest.country`;
 - `release_manifest.presentation`;
 - `release_manifest.publisher_labels`;
-- `calibration_diagnostics.dimensions` and `targets[].dimensions`; and
-- structured `targets[].source` and `targets[].variable` objects.
+- `calibration_diagnostics.dimensions`;
+- a `targets[].dimensions` object on every row, including `{}` where empty; and
+- structured `targets[].source` and `targets[].variable` objects on every row.
diff --git a/frontend/app/microcosm/page.tsx b/frontend/app/microcosm/page.tsx
index a61f5535..8b000029 100644
--- a/frontend/app/microcosm/page.tsx
+++ b/frontend/app/microcosm/page.tsx
@@ -1,10 +1,24 @@
 import { AppShell } from "@/components/layout/app-shell";
 import { MicrocosmOverviewView } from "@/components/microcosm/microcosm-overview-view";
+import { parseCountry } from "@/lib/microcosm/countries";
+
+interface MicrocosmOverviewPageProps {
+  searchParams?: Promise<Record<string, string | string[] | undefined>>;
+}
+
+export default async function MicrocosmOverviewPage({
+  searchParams,
+}: MicrocosmOverviewPageProps) {
+  const params = await searchParams;
+  const rawRelease = Array.isArray(params?.release) ? params.release[0] : params?.release;
+  const rawCountry = Array.isArray(params?.country) ? params.country[0] : params?.country;
 
-export default function MicrocosmOverviewPage() {
   return (
     <AppShell>
-      <MicrocosmOverviewView />
+      <MicrocosmOverviewView
+        initialCountry={parseCountry(rawCountry)}
+        initialRelease={rawRelease ?? ""}
+      />
     </AppShell>
   );
 }
diff --git a/frontend/app/microcosm/targets/page.tsx b/frontend/app/microcosm/targets/page.tsx
index 86558d64..6f709322 100644
--- a/frontend/app/microcosm/targets/page.tsx
+++ b/frontend/app/microcosm/targets/page.tsx
@@ -1,5 +1,6 @@
 import { AppShell } from "@/components/layout/app-shell";
 import { MicrocosmTargetsView } from "@/components/microcosm/microcosm-targets-view";
+import { parseCountry } from "@/lib/microcosm/countries";
 
 interface MicrocosmTargetsPageProps {
   searchParams?: Promise<Record<string, string | string[] | undefined>>;
@@ -13,6 +14,9 @@ export default async function MicrocosmTargetsPage({
   const initialScope = rawScope === "healthcare" ? "healthcare" : "all";
   const rawSource = Array.isArray(params?.source) ? params.source[0] : params?.source;
   const rawLevel = Array.isArray(params?.level) ? params.level[0] : params?.level;
+  const rawRelease = Array.isArray(params?.release) ? params.release[0] : params?.release;
+  const rawStart = Array.isArray(params?.start) ? params.start[0] : params?.start;
+  const rawCountry = Array.isArray(params?.country) ? params.country[0] : params?.country;
 
   return (
     <AppShell>
@@ -20,6 +24,9 @@ export default async function MicrocosmTargetsPage({
         initialScope={initialScope}
         initialSource={rawSource ?? ""}
         initialLevel={rawLevel ?? ""}
+        initialCountry={parseCountry(rawCountry)}
+        initialRelease={rawRelease ?? ""}
+        initialStep={rawStart === "explore" ? "pick" : "results"}
       />
     </AppShell>
   );
diff --git a/frontend/components/layout/country-context.test.ts b/frontend/components/layout/country-context.test.ts
index 10f378f4..10a9ed34 100644
--- a/frontend/components/layout/country-context.test.ts
+++ b/frontend/components/layout/country-context.test.ts
@@ -1,6 +1,10 @@
 import { expect, test } from "bun:test";
 
-import { countrySwitchUrl, isCountry } from "./country-context";
+import {
+  countrySwitchUrl,
+  isCountry,
+  selectedReleaseForCountry,
+} from "./country-context";
 
 test("country switching clears bundle-specific Cross-dataset state", () => {
   const switched = new URL(
@@ -14,16 +18,24 @@ test("country switching clears bundle-specific Cross-dataset state", () => {
   expect(switched.searchParams.toString()).toBe("country=be");
 });
 
-test("country switching preserves route state outside Cross-dataset", () => {
+test("country switching preserves route filters but clears the selected release", () => {
   const switched = new URL(
     countrySwitchUrl(
-      "https://example.test/microcosm/targets?country=us&variable=income_tax",
+      "https://example.test/microcosm/targets?country=us&release=us-build&variable=income_tax",
       "uk",
     ),
   );
 
   expect(switched.pathname).toBe("/microcosm/targets");
   expect(switched.searchParams.toString()).toBe("country=uk&variable=income_tax");
+  expect(switched.searchParams.has("release")).toBe(false);
+});
+
+test("a release selection is used only by the country that supplied it", () => {
+  const selection = { country: "us" as const, value: "us-build" };
+
+  expect(selectedReleaseForCountry("us", selection)).toBe("us-build");
+  expect(selectedReleaseForCountry("be", selection)).toBe("");
 });
 
 test("the client country parser accepts every registered country and nothing else", () => {
diff --git a/frontend/components/layout/country-context.tsx b/frontend/components/layout/country-context.tsx
index 46f5f74c..4e8d4a4b 100644
--- a/frontend/components/layout/country-context.tsx
+++ b/frontend/components/layout/country-context.tsx
@@ -7,6 +7,7 @@ import {
   useState,
   type ReactNode,
 } from "react";
+import { useRouter } from "next/navigation";
 
 import {
   DEFAULT_COUNTRY,
@@ -16,6 +17,11 @@ import {
 
 export type Country = MicrocosmCountry;
 
+export interface CountryReleaseSelection {
+  country: Country;
+  value: string;
+}
+
 export { isCountry };
 
 const STORAGE_KEY = "microcosm-country";
@@ -24,11 +30,22 @@ export function countrySwitchUrl(currentUrl: string, next: Country): string {
   const url = new URL(currentUrl);
   if (url.pathname.endsWith("/microcosm/datasets")) {
     url.search = "";
+  } else {
+    // Release identifiers are repository-specific. A release selected for one
+    // country must never be requested from another country's repository.
+    url.searchParams.delete("release");
   }
   url.searchParams.set("country", next);
   return url.toString();
 }
 
+export function selectedReleaseForCountry(
+  country: Country,
+  selection: CountryReleaseSelection,
+): string {
+  return selection.country === country ? selection.value : "";
+}
+
 function persistCountry(country: Country) {
   try {
     window.localStorage.setItem(STORAGE_KEY, country);
@@ -48,6 +65,7 @@ const CountryContext = createContext<CountryContextValue>({
 });
 
 export function CountryProvider({ children }: { children: ReactNode }) {
+  const router = useRouter();
   const [country, setCountryState] = useState<Country>(DEFAULT_COUNTRY);
 
   useEffect(() => {
@@ -65,11 +83,9 @@ export function CountryProvider({ children }: { children: ReactNode }) {
     if (next === country) return;
     setCountryState(next);
     persistCountry(next);
-    window.history.replaceState(
-      window.history.state,
-      "",
-      countrySwitchUrl(window.location.href, next),
-    );
+    // Route through Next so server page search parameters are recalculated;
+    // raw history replacement would leave initialRelease props stale.
+    router.replace(countrySwitchUrl(window.location.href, next), { scroll: false });
   };
 
   return (
diff --git a/frontend/components/layout/nav-items.test.ts b/frontend/components/layout/nav-items.test.ts
index fe001f4c..6e5da1f2 100644
--- a/frontend/components/layout/nav-items.test.ts
+++ b/frontend/components/layout/nav-items.test.ts
@@ -16,15 +16,11 @@ function datasetAccuracyItems() {
   return group.items;
 }
 
-test("shows calibration targets directly under calibration fit", () => {
+test("keeps calibration targets out of the sidebar", () => {
   const items = datasetAccuracyItems();
-  const labels = items.map((item) => item.label);
-  const calibrationFitIndex = labels.indexOf("Calibration fit");
-  const calibrationTargetsIndex = labels.indexOf("Calibration targets");
 
-  expect(calibrationFitIndex).toBeGreaterThanOrEqual(0);
-  expect(calibrationTargetsIndex).toBe(calibrationFitIndex + 1);
-  expect(items[calibrationTargetsIndex]?.href).toBe("/microcosm/targets");
+  expect(items.some((item) => item.label === "Calibration targets")).toBe(false);
+  expect(items.some((item) => item.href === "/microcosm/targets")).toBe(false);
 });
 
 test("places external checks at the bottom of dataset accuracy", () => {
@@ -43,19 +39,17 @@ test("models the external checks icon separately from its label", () => {
   expect(externalChecks?.external).toBe(true);
 });
 
-test("targets path activates calibration targets instead of calibration fit", () => {
+test("targets path does not activate calibration fit", () => {
   const items = datasetAccuracyItems();
   const calibrationFit = items.find((item) => item.label === "Calibration fit");
-  const calibrationTargets = items.find((item) => item.label === "Calibration targets");
 
-  if (!calibrationFit || !calibrationTargets) {
-    throw new Error("Calibration nav items not found");
+  if (!calibrationFit) {
+    throw new Error("Calibration fit nav item not found");
   }
 
   expect(calibrationFit.also ?? []).not.toContain("/microcosm/targets");
   expect(isActive("/microcosm", calibrationFit)).toBe(true);
   expect(isActive("/microcosm/targets", calibrationFit)).toBe(false);
-  expect(isActive("/microcosm/targets", calibrationTargets)).toBe(true);
 });
 test("opens external navigation in a new tab without changing internal navigation", () => {
   const items = datasetAccuracyItems();
@@ -105,14 +99,12 @@ test("Belgium navigation keeps country-ready pages and hides pages it lacks capa
   const items = navGroupsForCountry("be").flatMap((group) => group.items);
   expect(items.map((item) => item.href)).toEqual([
     "/microcosm",
-    "/microcosm/targets",
     "/microcosm/datasets",
     "/microcosm/compare",
   ]);
   expect(items.every((item) => hasCapability("be", item.capability!))).toBe(true);
   expect(items.map((item) => navItemHref(item, "be"))).toEqual([
     "/microcosm?country=be",
-    "/microcosm/targets?country=be",
     "/microcosm/datasets?country=be",
     "/microcosm/compare?country=be",
   ]);
@@ -127,10 +119,7 @@ test("US navigation lists every page", () => {
 test("artifact-narrowed capabilities hide pages the release does not serve", () => {
   const groups = navGroupsForCountry("us", ["calibration", "targets"]);
   expect(groups.map((group) => group.label)).toEqual(["Dataset accuracy"]);
-  expect(groups[0].items.map((item) => item.href)).toEqual([
-    "/microcosm",
-    "/microcosm/targets",
-  ]);
+  expect(groups[0].items.map((item) => item.href)).toEqual(["/microcosm"]);
 });
 
 test("shows Cross-dataset navigation for every selectable country", () => {
diff --git a/frontend/components/layout/nav-items.ts b/frontend/components/layout/nav-items.ts
index d3d48127..9c709605 100644
--- a/frontend/components/layout/nav-items.ts
+++ b/frontend/components/layout/nav-items.ts
@@ -24,7 +24,6 @@ export const NAV_GROUPS: { label: string; items: NavItem[] }[] = [
     label: "Dataset accuracy",
     items: [
       { href: "/microcosm", label: "Calibration fit", capability: "calibration" },
-      { href: "/microcosm/targets", label: "Calibration targets", capability: "targets" },
       {
         href: "/microcosm/model-coverage",
         label: "Validation reach",
diff --git a/frontend/components/microcosm/calibration-map.tsx b/frontend/components/microcosm/calibration-map.tsx
index e35623de..9e7f9c89 100644
--- a/frontend/components/microcosm/calibration-map.tsx
+++ b/frontend/components/microcosm/calibration-map.tsx
@@ -38,7 +38,9 @@ function isSynthetic(key: string): boolean {
 }
 
 function variableName(leaf: MicrocosmTreemapLeaf): string {
-  return isSynthetic(leaf.key) ? leaf.variable : humanizeName(leaf.variable) || leaf.variable;
+  return isSynthetic(leaf.key)
+    ? leaf.variable
+    : leaf.label ?? (humanizeName(leaf.variable) || leaf.variable);
 }
 
 function measureLabel(measure: string | null): string | null {
@@ -89,6 +91,7 @@ function aggregateLeaves(
     key,
     source,
     variable,
+    label: null,
     measure: null,
     measure_counts: [],
     n_targets: leaves.reduce((a, c) => a + c.n_targets, 0),
diff --git a/frontend/components/microcosm/calibration-target-navigation-cards.tsx b/frontend/components/microcosm/calibration-target-navigation-cards.tsx
new file mode 100644
index 00000000..044473eb
--- /dev/null
+++ b/frontend/components/microcosm/calibration-target-navigation-cards.tsx
@@ -0,0 +1,144 @@
+"use client";
+
+import { useMemo } from "react";
+import Link from "next/link";
+
+import { useCountry } from "@/components/layout/country-context";
+import { fmt } from "@/components/shared/format";
+import { useMicrocosmTargetDiagnostics } from "@/lib/api/hooks/use-microcosm";
+import { microcosmTargetsIntro } from "@/lib/microcosm/presentation";
+
+type TargetDestination = "explore" | "healthcare" | "everything";
+type CardAccent = "teal" | "slate";
+
+const ACCENTS: Record<
+  CardAccent,
+  { ink: string; border: string; glow: string }
+> = {
+  teal: {
+    ink: "text-primary",
+    border: "hover:border-primary/50",
+    glow: "wiz-glow-teal",
+  },
+  slate: {
+    ink: "text-muted-foreground",
+    border: "hover:border-border-dark",
+    glow: "wiz-glow-neutral",
+  },
+};
+
+function targetHref(
+  country: string,
+  release: string,
+  destination: TargetDestination,
+): string {
+  const params = new URLSearchParams({ country });
+  if (release) params.set("release", release);
+  if (destination === "explore") params.set("start", "explore");
+  if (destination === "healthcare") params.set("scope", "healthcare");
+  return `/microcosm/targets?${params.toString()}`;
+}
+
+function TargetNavigationCard({
+  eyebrow,
+  title,
+  body,
+  stat,
+  accent,
+  href,
+}: {
+  eyebrow: string;
+  title: string;
+  body: string;
+  stat: string;
+  accent: CardAccent;
+  href: string;
+}) {
+  const styles = ACCENTS[accent];
+  return (
+    <Link
+      href={href}
+      className={`group relative flex h-full flex-col gap-5 rounded-2xl border border-border bg-card p-6 text-left shadow-[var(--elev-2)] transition-all duration-200 hover:-translate-y-1 ${styles.border} ${styles.glow} focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-primary`}
+    >
+      <span
+        className={`text-[11px] font-semibold uppercase tracking-[0.14em] ${styles.ink}`}
+      >
+        {eyebrow}
+      </span>
+      <div className="flex-1">
+        <h3 className="text-xl font-semibold leading-snug tracking-tight text-foreground">
+          {title}
+        </h3>
+        <p className="mt-2 text-sm leading-relaxed text-muted-foreground">{body}</p>
+      </div>
+      <div className="flex items-center justify-between border-t border-border/60 pt-4">
+        <span className={`text-sm font-semibold tabular-nums ${styles.ink}`}>{stat}</span>
+        <span
+          className={`grid h-8 w-8 place-items-center rounded-full border border-border text-muted-foreground transition-all group-hover:translate-x-0.5 group-hover:border-current ${styles.ink}`}
+          aria-hidden
+        >
+          →
+        </span>
+      </div>
+    </Link>
+  );
+}
+
+export function CalibrationTargetNavigationCards({ release }: { release?: string }) {
+  const { country } = useCountry();
+  const { data, isPlaceholderData } = useMicrocosmTargetDiagnostics({
+    release,
+    limit: 1,
+  });
+  const variableGroupCount = useMemo(
+    () =>
+      new Set(
+        (data?.variables ?? []).map((variable) =>
+          [variable.source, variable.level, variable.variable].join("::"),
+        ),
+      ).size,
+    [data?.variables],
+  );
+  const hasHealthcareTargets =
+    !isPlaceholderData && (data?.scope_counts?.healthcare ?? 0) > 0;
+  const allTargets = data?.total_targets ?? null;
+
+  return (
+    <div className="grid gap-5 sm:grid-cols-2 lg:grid-cols-3">
+      <TargetNavigationCard
+        eyebrow="Browse"
+        title="Explore a statistic"
+        body={microcosmTargetsIntro(country, data?.presentation)}
+        stat={
+          variableGroupCount
+            ? `${fmt(variableGroupCount, { digits: 0 })} statistics`
+            : "Browse measures"
+        }
+        accent="teal"
+        href={targetHref(country, release ?? "", "explore")}
+      />
+      {hasHealthcareTargets ? (
+        <TargetNavigationCard
+          eyebrow="Focus"
+          title="Healthcare programs"
+          body="ACA marketplace, Medicaid, CHIP, and Medicare enrollment and premium targets."
+          stat="ACA · Medicaid · Medicare"
+          accent="teal"
+          href={targetHref(country, release ?? "", "healthcare")}
+        />
+      ) : null}
+      <TargetNavigationCard
+        eyebrow="Everything"
+        title="See everything"
+        body="Browse the full target surface with all filters and column sorting."
+        stat={
+          allTargets != null
+            ? `${fmt(allTargets, { digits: 0 })} targets`
+            : "All targets"
+        }
+        accent="slate"
+        href={targetHref(country, release ?? "", "everything")}
+      />
+    </div>
+  );
+}
diff --git a/frontend/components/microcosm/cluster-detail.tsx b/frontend/components/microcosm/cluster-detail.tsx
index 06e66e6d..54a6c390 100644
--- a/frontend/components/microcosm/cluster-detail.tsx
+++ b/frontend/components/microcosm/cluster-detail.tsx
@@ -141,7 +141,9 @@ export function ClusterDetail({
     .filter((d) => d.values.length > 0);
   const filteredTotal = data?.filtered_total ?? rows.length;
   const within = leaf.scored > 0 ? leaf.within_10pct / leaf.scored : null;
-  const name = synthetic ? leaf.variable : humanizeName(leaf.variable) || leaf.variable;
+  const name = synthetic
+    ? leaf.variable
+    : leaf.label ?? (humanizeName(leaf.variable) || leaf.variable);
   const measureOptions = (leaf.measure_counts ?? []).filter((option) => option.measure);
   const showMeasureFilter = !synthetic && Boolean(filters.program) && measureOptions.length > 1;
   const hasFilters =
diff --git a/frontend/components/microcosm/microcosm-overview-view.tsx b/frontend/components/microcosm/microcosm-overview-view.tsx
index 87b3f6d1..f5f3a757 100644
--- a/frontend/components/microcosm/microcosm-overview-view.tsx
+++ b/frontend/components/microcosm/microcosm-overview-view.tsx
@@ -7,9 +7,14 @@ import {
   CalibrationExplorerDataPrefetch,
   CalibrationExplorerMap,
 } from "@/components/microcosm/calibration-explorer-map";
+import { CalibrationTargetNavigationCards } from "@/components/microcosm/calibration-target-navigation-cards";
 import { ArtifactDescriptionBanner } from "@/components/microcosm/artifact-description-banner";
 import { WEIGHTED_TARGET_ERROR_HELP } from "@/components/microcosm/calibration-explorer-view";
-import { useCountry } from "@/components/layout/country-context";
+import {
+  selectedReleaseForCountry,
+  useCountry,
+  type Country,
+} from "@/components/layout/country-context";
 import { EmptyState } from "@/components/shared/empty-state";
 import { fmt, fmtCompact } from "@/components/shared/format";
 import { HelpHint } from "@/components/shared/help-hint";
@@ -70,9 +75,19 @@ function OverviewMetric({ label, value }: { label: ReactNode; value: string }) {
   );
 }
 
-export function MicrocosmOverviewView() {
+export function MicrocosmOverviewView({
+  initialCountry = "us",
+  initialRelease = "",
+}: {
+  initialCountry?: Country;
+  initialRelease?: string;
+}) {
   const { country } = useCountry();
-  const [release, setRelease] = useState("");
+  const [releaseSelection, setReleaseSelection] = useState({
+    country: initialCountry,
+    value: initialRelease,
+  });
+  const release = selectedReleaseForCountry(country, releaseSelection);
   const [pageIntroHeight, setPageIntroHeight] = useState(0);
   const { data: releaseData } = useMicrocosmReleases();
   const { data, isLoading, error } = useMicrocosm(release || undefined);
@@ -140,7 +155,7 @@ export function MicrocosmOverviewView() {
             <ToolbarSelect
               label="Release"
               value={release}
-              onChange={setRelease}
+              onChange={(value) => setReleaseSelection({ country, value })}
               options={releaseOptions}
             />
             <Button
@@ -245,6 +260,10 @@ export function MicrocosmOverviewView() {
         />
       </SectionCard>
 
+      <SectionCard title="Calibration target details">
+        <CalibrationTargetNavigationCards release={release || undefined} />
+      </SectionCard>
+
       <SectionCard title="Limitations">
         <ul className="list-disc space-y-1 pl-5 text-sm text-muted-foreground">
           {data.limitations.map((limitation) => (
diff --git a/frontend/components/microcosm/microcosm-targets-view.tsx b/frontend/components/microcosm/microcosm-targets-view.tsx
index 99edfec3..7ae7315c 100644
--- a/frontend/components/microcosm/microcosm-targets-view.tsx
+++ b/frontend/components/microcosm/microcosm-targets-view.tsx
@@ -1,10 +1,15 @@
 "use client";
 
 import { useEffect, useMemo, useState } from "react";
+import { useRouter } from "next/navigation";
 
 import { EmptyState } from "@/components/shared/empty-state";
 import { fmt, fmtCompact, humanizeName, releaseLabel } from "@/components/shared/format";
-import { useCountry } from "@/components/layout/country-context";
+import {
+  selectedReleaseForCountry,
+  useCountry,
+  type Country,
+} from "@/components/layout/country-context";
 import { ArtifactDescriptionBanner } from "@/components/microcosm/artifact-description-banner";
 import { KpiCard } from "@/components/shared/kpi-card";
 import { LoadingBlock } from "@/components/shared/LoadingBlock";
@@ -12,9 +17,7 @@ import { PageHeader } from "@/components/shared/page-header";
 import { SectionCard } from "@/components/shared/section-card";
 import { ToolbarSelect } from "@/components/shared/toolbar-select";
 import { MicrocosmTargetDetail } from "@/components/microcosm/microcosm-target-detail";
-import { withBasePath } from "@/lib/base-path";
 import { hasCapability } from "@/lib/microcosm/countries";
-import { microcosmTargetsIntro } from "@/lib/microcosm/presentation";
 import { sourceLabel } from "@/lib/microcosm/source-label";
 import {
   releaseSelectOptions,
@@ -476,87 +479,27 @@ function VariableBrowser({
   );
 }
 
-type WizardStep = "home" | "pick" | "refine" | "results";
-type WizardAccent = "teal" | "amber" | "slate";
-
-const ACCENTS: Record<
-  WizardAccent,
-  { chip: string; ink: string; border: string; glow: string }
-> = {
-  teal: {
-    chip: "bg-primary/10 text-primary",
-    ink: "text-primary",
-    border: "hover:border-primary/50",
-    glow: "wiz-glow-teal",
-  },
-  amber: {
-    chip: "pill-warn",
-    ink: "tone-warn",
-    border: "hover:border-[var(--warn)]",
-    glow: "wiz-glow-warn",
-  },
-  slate: {
-    chip: "pill-neutral",
-    ink: "text-muted-foreground",
-    border: "hover:border-border-dark",
-    glow: "wiz-glow-neutral",
-  },
-};
-
-function WizardCard({
-  eyebrow,
-  title,
-  body,
-  stat,
-  accent,
-  onClick,
-}: {
-  eyebrow: string;
-  title: string;
-  body: string;
-  stat: string;
-  accent: WizardAccent;
-  onClick: () => void;
-}) {
-  const a = ACCENTS[accent];
-  return (
-    <button
-      type="button"
-      onClick={onClick}
-      className={`group relative flex h-full flex-col gap-5 rounded-2xl border border-border bg-card p-6 text-left shadow-[var(--elev-2)] transition-all duration-200 hover:-translate-y-1 ${a.border} ${a.glow} focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-primary`}
-    >
-      <span className={`text-[11px] font-semibold uppercase tracking-[0.14em] ${a.ink}`}>
-        {eyebrow}
-      </span>
-      <div className="flex-1">
-        <h3 className="text-xl font-semibold leading-snug tracking-tight text-foreground">
-          {title}
-        </h3>
-        <p className="mt-2 text-sm leading-relaxed text-muted-foreground">{body}</p>
-      </div>
-      <div className="flex items-center justify-between border-t border-border/60 pt-4">
-        <span className={`text-sm font-semibold tabular-nums ${a.ink}`}>{stat}</span>
-        <span
-          className={`grid h-8 w-8 place-items-center rounded-full border border-border text-muted-foreground transition-all group-hover:translate-x-0.5 group-hover:border-current ${a.ink}`}
-          aria-hidden
-        >
-          →
-        </span>
-      </div>
-    </button>
-  );
-}
+type WizardStep = "pick" | "refine" | "results";
 
 export function MicrocosmTargetsView({
   initialScope = "all",
   initialSource = "",
   initialLevel = "",
+  initialCountry = "us",
+  initialRelease = "",
+  initialStep = "results",
 }: {
   initialScope?: TargetScope;
   initialSource?: string;
   initialLevel?: string;
+  initialCountry?: Country;
+  initialRelease?: string;
+  initialStep?: "pick" | "results";
 }) {
-  const [release, setRelease] = useState("");
+  const [releaseSelection, setReleaseSelection] = useState({
+    country: initialCountry,
+    value: initialRelease,
+  });
   const [scope, setScope] = useState<TargetScope>(initialScope);
   const [variable, setVariable] = useState("");
   const [source, setSource] = useState(initialSource);
@@ -569,11 +512,13 @@ export function MicrocosmTargetsView({
   const [selected, setSelected] = useState<MicrocosmTargetRow | null>(null);
   const [page, setPage] = useState(0);
   const [sort, setSort] = useState<SortState>({ by: "abs_relative_error", dir: "desc" });
-  const [step, setStep] = useState<WizardStep>(initialSource ? "results" : "home");
+  const [step, setStep] = useState<WizardStep>(initialSource ? "results" : initialStep);
   const [showAdvanced, setShowAdvanced] = useState(false);
   const [refineIndex, setRefineIndex] = useState(0);
 
   const { country } = useCountry();
+  const release = selectedReleaseForCountry(country, releaseSelection);
+  const router = useRouter();
   const { data: releaseData } = useMicrocosmReleases();
   const { data: stagingData } = useMicrocosmStagingRuns();
   const releaseOptions = useMemo(
@@ -593,7 +538,7 @@ export function MicrocosmTargetsView({
 
   function pickRelease(value: string) {
     // A different release is a different surface — reset everything below it.
-    setRelease(value);
+    setReleaseSelection({ country, value });
     setVariable("");
     setFacetFilters({});
     setSource("");
@@ -621,28 +566,14 @@ export function MicrocosmTargetsView({
     setPage(0);
   }
 
-  function startOver() {
-    resetFilters();
-    setStep("home");
-  }
-
-  function startExplore() {
-    resetFilters();
-    setStep("pick");
-  }
-
-  function startHealthcare() {
-    resetFilters();
-    setScope("healthcare");
-    setStep("results");
-  }
-
-  function startEverything() {
+  function returnToCalibrationFit() {
     resetFilters();
-    setStep("results");
+    const query = new URLSearchParams({ country });
+    if (release) query.set("release", release);
+    router.push(`/microcosm?${query.toString()}`);
   }
 
-  // Step back one level toward the starting cards.
+  // Step back one level toward the statistic picker.
   function goBack() {
     if (step === "results" && activeVariable) {
       setStep("refine");
@@ -652,7 +583,7 @@ export function MicrocosmTargetsView({
       setStep("pick");
       return;
     }
-    startOver();
+    returnToCalibrationFit();
   }
 
   const facetParam = useMemo(
@@ -697,7 +628,7 @@ export function MicrocosmTargetsView({
     ],
   );
 
-  const { data, isLoading, isFetching, error, isPlaceholderData } =
+  const { data, isLoading, isFetching, error } =
     useMicrocosmTargetDiagnostics(params);
 
   const variables = data?.variables ?? [];
@@ -711,12 +642,6 @@ export function MicrocosmTargetsView({
     [scope, variables],
   );
   const filteredTotal = data?.filtered_total ?? 0;
-  const allTargets = data?.total_targets ?? null;
-  // The healthcare focus is offered when the release has healthcare targets.
-  // Kept-previous placeholder data belongs to the prior country/release, so it
-  // must not decide the card.
-  const hasHealthcareTargets =
-    !isPlaceholderData && (data?.scope_counts?.healthcare ?? 0) > 0;
   const pageCount = Math.max(Math.ceil(filteredTotal / PAGE_SIZE), 1);
   const activeVariable = variables.find((v) => v.variable_key === variable);
 
@@ -1053,19 +978,7 @@ export function MicrocosmTargetsView({
       <PageHeader
         eyebrow="Microcosm · calibration fit"
         title="Target diagnostics"
-        description={
-          <>
-            See how closely the calibrated weights reproduce each official statistic — by
-            source, measure, and breakdown. This is the drill-down behind the{" "}
-            <a
-              href={withBasePath(`/microcosm?country=${country}`)}
-              className="text-primary hover:underline"
-            >
-              calibration map
-            </a>
-            .
-          </>
-        }
+        description="See how closely the calibrated weights reproduce each official statistic by source, measure, and breakdown."
         actions={
           <ToolbarSelect
             label="Release"
@@ -1078,61 +991,34 @@ export function MicrocosmTargetsView({
 
       <ArtifactDescriptionBanner description={data?.description} />
 
-      {step === "home" && (
-        <div className="flex flex-col gap-4">
-          <h2 className="text-base font-semibold text-foreground">
-            Where would you like to start?
-          </h2>
-          <div className="grid gap-5 sm:grid-cols-2 lg:grid-cols-3">
-            <WizardCard
-              eyebrow="Browse"
-              title="Explore a statistic"
-              body={microcosmTargetsIntro(country, data?.presentation)}
-              stat={variableGroupCount ? `${fmt(variableGroupCount, { digits: 0 })} statistics` : "Browse measures"}
-              accent="teal"
-              onClick={startExplore}
-            />
-            {hasHealthcareTargets ? (
-              <WizardCard
-                eyebrow="Focus"
-                title="Healthcare programs"
-                body="ACA marketplace, Medicaid, CHIP, and Medicare enrollment and premium targets."
-                stat="ACA · Medicaid · Medicare"
-                accent="teal"
-                onClick={startHealthcare}
-              />
-            ) : null}
-            <WizardCard
-              eyebrow="Everything"
-              title="See everything"
-              body="Browse the full target surface with all filters and column sorting."
-              stat={allTargets != null ? `${fmt(allTargets, { digits: 0 })} targets` : "All targets"}
-              accent="slate"
-              onClick={startEverything}
-            />
-          </div>
-        </div>
-      )}
-
       {step === "pick" && (
         <div className="flex flex-col gap-4">
           <div className="flex flex-wrap items-center gap-2 rounded-xl border border-border bg-card px-4 py-2.5 text-sm shadow-[var(--elev-2)]">
             <button
               type="button"
               onClick={goBack}
-              className="flex items-center gap-1 font-medium text-muted-foreground hover:text-foreground"
+              className="flex cursor-pointer items-center gap-1 font-medium text-muted-foreground hover:text-foreground"
             >
               <span aria-hidden>←</span> Back
             </button>
             <span className="text-muted-foreground/50">/</span>
             <span className="font-semibold text-foreground">Pick a statistic</span>
           </div>
-          <SectionCard
-            title="Which statistic?"
-            description={`${fmt(variableGroupCount, { digits: 0 })} measures in this release — pick one to see its breakdowns.`}
-          >
-            <VariableBrowser variables={variables} active={variable} onPick={pickVariable} />
-          </SectionCard>
+          {isLoading ? (
+            <LoadingBlock label="Loading target diagnostics…" />
+          ) : error || !data ? (
+            <EmptyState
+              title="Target diagnostics unavailable"
+              description={error instanceof Error ? error.message : "Unknown error."}
+            />
+          ) : (
+            <SectionCard
+              title="Which statistic?"
+              description={`${fmt(variableGroupCount, { digits: 0 })} measures in this release — pick one to see its breakdowns.`}
+            >
+              <VariableBrowser variables={variables} active={variable} onPick={pickVariable} />
+            </SectionCard>
+          )}
         </div>
       )}
 
@@ -1140,7 +1026,7 @@ export function MicrocosmTargetsView({
         <div className="flex flex-col gap-4">
           <div className="flex flex-wrap items-center justify-between gap-3 rounded-xl border border-border bg-card px-4 py-2.5 shadow-[var(--elev-2)]">
             <div className="flex min-w-0 flex-wrap items-center gap-2 text-sm">
-              <button type="button" onClick={goBack} className="flex items-center gap-1 font-medium text-muted-foreground hover:text-foreground">
+              <button type="button" onClick={goBack} className="flex cursor-pointer items-center gap-1 font-medium text-muted-foreground hover:text-foreground">
                 <span aria-hidden>←</span> Back
               </button>
               <span className="text-muted-foreground/50">/</span>
@@ -1151,7 +1037,7 @@ export function MicrocosmTargetsView({
             <div className="flex items-center gap-2">
               <button
                 type="button"
-                onClick={startOver}
+                onClick={returnToCalibrationFit}
                 className="rounded-md border border-border px-2.5 py-1 text-xs text-muted-foreground hover:bg-muted/60 hover:text-foreground"
               >
                 Start over
@@ -1275,7 +1161,7 @@ export function MicrocosmTargetsView({
               <button
                 type="button"
                 onClick={goBack}
-                className="flex items-center gap-1 font-medium text-muted-foreground hover:text-foreground"
+                className="flex cursor-pointer items-center gap-1 font-medium text-muted-foreground hover:text-foreground"
               >
                 <span aria-hidden>←</span> Back
               </button>
@@ -1307,7 +1193,7 @@ export function MicrocosmTargetsView({
               )}
               <button
                 type="button"
-                onClick={startOver}
+                onClick={returnToCalibrationFit}
                 className="rounded-md border border-border px-2.5 py-1 text-xs text-muted-foreground hover:bg-muted/60 hover:text-foreground"
               >
                 Start over
diff --git a/frontend/lib/api/hooks/use-microcosm.ts b/frontend/lib/api/hooks/use-microcosm.ts
index 42355127..77ff7e99 100644
--- a/frontend/lib/api/hooks/use-microcosm.ts
+++ b/frontend/lib/api/hooks/use-microcosm.ts
@@ -208,6 +208,7 @@ export interface MicrocosmArtifactPresentation {
 export interface MicrocosmTargetSchema {
   diagnostics_schema_version: number | null;
   structured_dimensions: boolean;
+  target_representation: "legacy" | "structured" | "mixed" | "unknown";
 }
 
 export interface MicrocosmCalibration {
@@ -746,6 +747,7 @@ export interface MicrocosmTreemapLeaf {
   key: string;
   source: string;
   variable: string;
+  label: string | null;
   measure: string | null;
   measure_counts: { measure: string | null; n_targets: number }[];
   filters?: {
diff --git a/frontend/lib/microcosm/calibration-tree.ts b/frontend/lib/microcosm/calibration-tree.ts
index 59663e45..80290aae 100644
--- a/frontend/lib/microcosm/calibration-tree.ts
+++ b/frontend/lib/microcosm/calibration-tree.ts
@@ -24,6 +24,7 @@ export interface CalibrationTreeTarget {
   source?: string | null;
   source_label?: string | null;
   variable?: string | null;
+  variable_label?: string | null;
   variable_key?: string | null;
   measure?: string | null;
   source_measure_id?: string | null;
@@ -415,15 +416,22 @@ function programGroups(rows: CalibrationTreeTarget[]): CalibrationTreeGroup[] {
         .find((label): label is string => Boolean(label));
       const byProgram = groupRows(sourceRows, programId);
       const nodes = sortNodes(
-        [...byProgram.entries()].map(([program, programRows]) =>
-          node(
+        [...byProgram.entries()].map(([program, programRows]) => {
+          const labels = [
+            ...new Set(
+              programRows
+                .map((row) => row.variable_label?.trim())
+                .filter((label): label is string => Boolean(label)),
+            ),
+          ];
+          return node(
             program,
-            programLabel(program),
+            programLabel(program, labels.length === 1 ? labels[0] : null),
             "program",
             { kind: "program", source, value: program },
             programRows,
-          ),
-        ),
+          );
+        }),
       );
       return {
         id: source,
diff --git a/frontend/lib/microcosm/fixtures/us-legacy-target-identities.json.gz b/frontend/lib/microcosm/fixtures/us-legacy-target-identities.json.gz
new file mode 100644
index 00000000..bc89ce86
Binary files /dev/null and b/frontend/lib/microcosm/fixtures/us-legacy-target-identities.json.gz differ
diff --git a/frontend/lib/microcosm/latest-artifact.test.ts b/frontend/lib/microcosm/latest-artifact.test.ts
index 886e402a..73acb2b0 100644
--- a/frontend/lib/microcosm/latest-artifact.test.ts
+++ b/frontend/lib/microcosm/latest-artifact.test.ts
@@ -198,7 +198,8 @@ test("structured dimensions shape rows and honor artifact value order", () => {
   ) => ({
     name: `fixture.population.${suffix}@2026`,
     target_name: `fixture.population.${suffix}`,
-    source: "ZZ official population table",
+    source: { id: "novastat_agency", citation: "ZZ official population table" },
+    variable: { id: "population", measure: "count" },
     metadata: {
       chronicle_record_ids: [`novastat_agency.population.${suffix}`],
       variable: "population",
@@ -256,6 +257,7 @@ test("structured dimensions shape rows and honor artifact value order", () => {
   expect(cal.target_schema).toEqual({
     diagnostics_schema_version: 7,
     structured_dimensions: true,
+    target_representation: "structured",
   });
   expect(cal.rows.every((row) => row.dimension_adapter === "structured")).toBe(true);
   expect(cal.rows[0]).toMatchObject({
@@ -304,7 +306,8 @@ test("structured dimensions shape rows and honor artifact value order", () => {
 test("structured facet ordering falls back when any displayed value lacks a rank", () => {
   const target = (suffix: string, category: string) => ({
     name: `fixture.population.${suffix}@2026`,
-    source: "Citation",
+    source: { id: "novastat_agency", citation: "Citation" },
+    variable: { id: "population", measure: "count" },
     metadata: {
       chronicle_record_ids: ["novastat_agency.population.total"],
       variable: "population",
@@ -338,7 +341,7 @@ test("structured facet ordering falls back when any displayed value lacks a rank
   ]);
 });
 
-test("dimension adapters are selected per row and structured values beat legacy filters", () => {
+test("mixed files select the dimension adapter from each complete row representation", () => {
   const base = {
     source: "ZZ official population table",
     metadata: {
@@ -366,6 +369,8 @@ test("dimension adapters are selected per row and structured values beat legacy
         {
           ...base,
           name: "fixture_population_north_female_0_17@2026",
+          source: { id: "novastat_agency", citation: "ZZ official population table" },
+          variable: { id: "population", measure: "count" },
           filter: "cell_south_male_65_plus",
           dimensions: { region: "north", sex: "female", age_band: "0_17" },
         },
@@ -401,7 +406,8 @@ test("dimension adapters are selected per row and structured values beat legacy
 
 test("structured rows do not require a dimensions dictionary, including empty objects", () => {
   const base = {
-    source: "Citation",
+    source: { id: "novastat_agency", citation: "Citation" },
+    variable: { id: "population", measure: "count" },
     metadata: { variable: "population", source_measure_id: "population_count" },
     filter: "cell_south_male_18_64",
     target: 1,
@@ -450,7 +456,8 @@ test("structured rows do not require a dimensions dictionary, including empty ob
 test("structured dimensions prevent whole-population estimate-scope warnings", () => {
   const target = (recordSet: string, category: string, targetValue: number) => ({
     name: `source.example.${category}.amount@2026`,
-    source: "Citation",
+    source: { id: "source", citation: "Citation" },
+    variable: { id: "example", measure: "amount" },
     metadata: {
       variable: "example",
       source_measure_id: "example_amount",
@@ -1846,7 +1853,250 @@ test("publisher label lookup does not read inherited object properties", () => {
   expect(cal.rows[0].source_label).toBe("Constructor");
 });
 
-test("structured source and variable fields follow artifact precedence", () => {
+test("fully structured targets ignore conflicting legacy identity fields", () => {
+  const cal = buildCalibration(
+    {
+      dimensions: {
+        region: {
+          label: "Region",
+          role: "geography",
+          level: "region",
+          values: { north: "North" },
+        },
+        sex: { label: "Sex", values: { female: "Female" } },
+      },
+      targets: [
+        {
+          name: "legacy.publisher.incorrect_variable.total@2026",
+          source: {
+            id: "novastat_agency",
+            citation: "Official population table",
+            label: "Nova Statistics Agency",
+            url: "https://stats.example/population",
+          },
+          variable: {
+            id: "resident_population",
+            label: "Resident population",
+            measure: "count",
+          },
+          dimensions: { region: "north", sex: "female" },
+          filter: "cell_be1_male_65_plus",
+          metadata: {
+            chronicle_record_ids: ["legacy_agency.incorrect.total"],
+            variable: "incorrect_variable",
+            ledger_geography_level: "state",
+            ledger_geography_id: "0400000US06",
+            ledger_layout_groupby_value_id: "incorrect_breakdown",
+          },
+          target: 100,
+          initial_estimate: 90,
+          final_estimate: 100,
+        },
+      ],
+    },
+    "structured-only",
+  );
+
+  expect(cal.target_schema.target_representation).toBe("structured");
+  expect(cal.rows[0]).toMatchObject({
+    family: "novastat_agency/resident_population",
+    source: "novastat_agency",
+    source_label: "Nova Statistics Agency",
+    source_citation: "Official population table",
+    source_url: "https://stats.example/population",
+    variable: "resident_population",
+    variable_label: "Resident population",
+    measure: "count",
+    geography: "North",
+    level: "region",
+    state: null,
+    breakdown: "Female",
+    dimension_adapter: "structured",
+    variable_key: "novastat_agency / resident_population · count",
+    target_dimensions: [
+      expect.objectContaining({ key: "bd_sex", label: "Sex", value: "Female" }),
+    ],
+  });
+  const map = microcosmTargetTreemap(cal.rows, cal.release_id);
+  expect(map.groups[0]).toMatchObject({
+    source: "novastat_agency",
+    label: "Nova Statistics Agency",
+  });
+  expect(map.groups[0].children[0]).toMatchObject({
+    variable: "resident_population",
+    label: "Resident population",
+  });
+  const tree = buildCalibrationTree(cal.rows, {
+    breakdown: "program",
+    path: { dimensions: [] },
+    filters: {
+      geographyLevels: [],
+      geographies: [],
+      fitBands: [],
+      calibrationStatuses: [],
+    },
+  });
+  expect(tree.groups[0].nodes[0]).toMatchObject({
+    id: "resident_population",
+    label: "Resident population",
+  });
+});
+
+test("structured dimension ids remain independent when display labels repeat", () => {
+  const structuredTargets = [
+    ["north", "east"],
+    ["north", "west"],
+    ["south", "east"],
+    ["south", "west"],
+  ].map(([origin, destination], index) => ({
+    name: `population-${index}`,
+    source: { id: "agency" },
+    variable: { id: "population", measure: "count" },
+    dimensions: { origin, destination },
+    target: 100,
+    initial_estimate: 90,
+    final_estimate: 100,
+  }));
+  const diagnostics = {
+    dimensions: {
+      origin: {
+        label: "Region",
+        values: { north: "North", south: "South" },
+      },
+      destination: {
+        label: "Region",
+        values: { east: "East", west: "West" },
+      },
+    },
+    targets: structuredTargets,
+  };
+  const cal = buildCalibration(diagnostics, "repeated-dimension-labels");
+
+  expect(cal.rows[0].target_dimensions).toEqual([
+    expect.objectContaining({ key: "bd_origin", label: "Region", value: "North" }),
+    expect.objectContaining({ key: "bd_destination", label: "Region", value: "East" }),
+  ]);
+
+  const requestUrl = new URL("http://x/api/microcosm/target-diagnostics");
+  requestUrl.searchParams.set("variable", "agency / population · count");
+  requestUrl.searchParams.append("facet", "bd_origin:North");
+  requestUrl.searchParams.append("facet", "bd_destination:East");
+  const page = latestMicrocosmTargetDiagnosticsPage(requestUrl.toString(), cal);
+  expect(page.dimensions).toEqual([
+    { key: "bd_origin", label: "Region", values: ["North", "South"] },
+    { key: "bd_destination", label: "Region", values: ["East", "West"] },
+  ]);
+  expect(page.filtered_total).toBe(1);
+
+  const treeState = {
+    breakdown: "program" as const,
+    path: {
+      source: "agency",
+      program: "population",
+      geography: "United States",
+      dimensions: [],
+    },
+    filters: {
+      geographyLevels: [],
+      geographies: [],
+      fitBands: [],
+      calibrationStatuses: [],
+    },
+  };
+  const tree = buildCalibrationTree(cal.rows, treeState);
+  expect(tree.dimensionOrder).toEqual([
+    { key: "bd_destination", label: "Region" },
+    { key: "bd_origin", label: "Region" },
+  ]);
+  expect(tree.groups[0]?.id).toBe("bd_destination");
+  const destinationTree = buildCalibrationTree(cal.rows, {
+    ...treeState,
+    path: {
+      ...treeState.path,
+      dimensions: [{ key: "bd_destination", label: "Region", value: "East" }],
+    },
+  });
+  expect(destinationTree.groups[0]?.id).toBe("bd_origin");
+
+  const mixed = buildCalibration(
+    {
+      ...diagnostics,
+      targets: [
+        ...structuredTargets,
+        {
+          name: "nation/legacy/population",
+          target: 1,
+          initial_estimate: 1,
+          final_estimate: 1,
+        },
+      ],
+    },
+    "mixed-repeated-dimension-labels",
+  );
+  expect(mixed.target_schema.target_representation).toBe("mixed");
+  expect(mixed.rows[0].target_dimensions).toEqual(cal.rows[0].target_dimensions);
+});
+
+test("mixed diagnostics dispatch complete legacy and structured rows independently", () => {
+  const cal = buildCalibration(
+    {
+      targets: [
+        {
+          name: "bea_nipa.cy2023.proprietors_income.a041rc.amount@2024",
+          source: "BEA citation",
+          metadata: {
+            chronicle_record_ids: ["bea.nipa.proprietors_income.amount"],
+            source_measure_id: "amount",
+            ledger_geography_level: "country",
+          },
+          target: 100,
+          initial_estimate: 90,
+          final_estimate: 99,
+        },
+        {
+          name: "legacy.publisher.population.total@2026",
+          source: {
+            id: "artifact_agency",
+            citation: "Official population table",
+            label: "Artifact agency",
+          },
+          variable: {
+            id: "resident_population",
+            label: "Resident population",
+            measure: "count",
+          },
+          dimensions: {},
+          metadata: {
+            chronicle_record_ids: ["chronicle_agency.population.total"],
+            variable: "legacy_population",
+          },
+          target: 100,
+          initial_estimate: 90,
+          final_estimate: 100,
+        },
+      ],
+    },
+    "mixed-identities",
+  );
+
+  expect(cal.target_schema.target_representation).toBe("mixed");
+  expect(cal.rows[0]).toMatchObject({
+    source: "bea",
+    variable: "amount",
+    dimension_adapter: "legacy_name",
+  });
+  expect(cal.rows[1]).toMatchObject({
+    source: "artifact_agency",
+    source_label: "Artifact agency",
+    source_citation: "Official population table",
+    variable: "resident_population",
+    variable_label: "Resident population",
+    measure: "count",
+    dimension_adapter: "structured",
+  });
+});
+
+test("structured source and variable fields remain authoritative", () => {
   const target = {
     name: "legacy.publisher.population.total@2026",
     source: {
@@ -1860,6 +2110,7 @@ test("structured source and variable fields follow artifact precedence", () => {
       label: "Resident population",
       measure: "mean",
     },
+    dimensions: {},
     metadata: {
       chronicle_record_ids: ["chronicle_agency.population.total"],
       variable: "legacy_population",
@@ -1874,18 +2125,18 @@ test("structured source and variable fields follow artifact precedence", () => {
     "structured-identifiers",
     null,
     {},
-    { publisher_labels: { chronicle_agency: "Manifest agency label" } },
+    { publisher_labels: { artifact_agency: "Manifest agency label" } },
   );
 
   expect(cal.rows[0]).toMatchObject({
-    source: "chronicle_agency",
+    source: "artifact_agency",
     source_label: "Manifest agency label",
     source_citation: "Official population table",
     source_url: "https://stats.example/population",
     variable: "resident_population",
     variable_label: "Resident population",
     measure: "mean",
-    variable_key: "chronicle_agency / resident_population · mean",
+    variable_key: "artifact_agency / resident_population · mean",
   });
   const response = latestMicrocosmTargetDiagnosticsPage(
     "http://x/api/microcosm/target-diagnostics",
diff --git a/frontend/lib/microcosm/latest-artifact.ts b/frontend/lib/microcosm/latest-artifact.ts
index f2110601..6032263d 100644
--- a/frontend/lib/microcosm/latest-artifact.ts
+++ b/frontend/lib/microcosm/latest-artifact.ts
@@ -6,6 +6,13 @@
 import { sourceAuthorityLabel } from "@/lib/source-labels";
 
 import { normalizeChronicleMetadata } from "./chronicle-metadata";
+import {
+  chroniclePublisherFromMetadata,
+  qualifyingChildrenFromRecordSet,
+  readLegacyTarget,
+  stateFromGeoId,
+  type ParsedLegacyTarget,
+} from "./legacy-target-reader";
 import {
   COUNTRY_REGISTRY,
   DEFAULT_COUNTRY,
@@ -23,6 +30,12 @@ import {
   type FinalTargetLossAttribution,
   type TargetLossDiagnosticWarning,
 } from "./target-loss-attribution";
+import {
+  classifyTargetRow,
+  classifyTargetRepresentation,
+  type TargetRepresentation,
+} from "./target-representation";
+import { readStructuredTarget } from "./structured-target-reader";
 
 // The registry is the registration point; these re-exports keep the server
 // modules and routes that import country helpers from here working.
@@ -125,24 +138,6 @@ function hfAuthHeaders(): HeadersInit | undefined {
   return token ? { Authorization: `Bearer ${token}` } : undefined;
 }
 
-// --- name decomposition (matches microcosm.institute's parse_target) ---------------
-const FIPS_TO_ABBR: Record<string, string> = {
-  "01": "AL", "02": "AK", "04": "AZ", "05": "AR", "06": "CA", "08": "CO",
-  "09": "CT", "10": "DE", "11": "DC", "12": "FL", "13": "GA", "15": "HI",
-  "16": "ID", "17": "IL", "18": "IN", "19": "IA", "20": "KS", "21": "KY",
-  "22": "LA", "23": "ME", "24": "MD", "25": "MA", "26": "MI", "27": "MN",
-  "28": "MS", "29": "MO", "30": "MT", "31": "NE", "32": "NV", "33": "NH",
-  "34": "NJ", "35": "NM", "36": "NY", "37": "NC", "38": "ND", "39": "OH",
-  "40": "OK", "41": "OR", "42": "PA", "44": "RI", "45": "SC", "46": "SD",
-  "47": "TN", "48": "TX", "49": "UT", "50": "VT", "51": "VA", "53": "WA",
-  "54": "WV", "55": "WI", "56": "WY",
-};
-const STATE_ABBRS = new Set([
-  "AL", "AK", "AZ", "AR", "CA", "CO", "CT", "DE", "DC", "FL", "GA", "HI", "ID",
-  "IL", "IN", "IA", "KS", "KY", "LA", "ME", "MD", "MA", "MI", "MN", "MS", "MO",
-  "MT", "NE", "NV", "NH", "NJ", "NM", "NY", "NC", "ND", "OH", "OK", "OR", "PA",
-  "RI", "SC", "SD", "TN", "TX", "UT", "VT", "VA", "WA", "WV", "WI", "WY", "US",
-]);
 const FILING_MODIFIERS = new Set(["Surviving Spouse"]);
 const FILING_STATUSES = new Set([
   "All", "Single", "Head of Household", "Married Filing Jointly",
@@ -225,13 +220,7 @@ function relativeError(estimate: number | null, target: number | null): number |
   return (estimate - target) / Math.abs(target);
 }
 
-interface ParsedTarget {
-  geography: string;
-  level: string;
-  source: string;
-  variable: string;
-  breakdown: string;
-}
+type ParsedTarget = ParsedLegacyTarget;
 
 interface TargetBreakdownDimension {
   key: string;
@@ -287,22 +276,6 @@ function stringValue(value: unknown): string | null {
   return typeof value === "string" && value.trim() ? value : null;
 }
 
-function stateFromGeoId(value: string | null): string | null {
-  if (!value) return null;
-  const match = /US(\d{2})$/.exec(value);
-  return match ? FIPS_TO_ABBR[match[1]] ?? null : null;
-}
-
-// Census CD geo ids end in SSDD (state FIPS + district number), e.g.
-// 5001700US0101 -> AL-01.
-function districtFromGeoId(value: string | null): string | null {
-  if (!value) return null;
-  const match = /US(\d{2})(\d{2})$/.exec(value);
-  if (!match) return null;
-  const state = FIPS_TO_ABBR[match[1]];
-  return state ? `${state}-${match[2]}` : null;
-}
-
 function readableToken(value: string | null): string | null {
   if (!value) return null;
   return value.replace(/_/g, " ");
@@ -341,51 +314,6 @@ function addDimension(
   });
 }
 
-function variableFromMeasure(value: string | null): string | null {
-  if (!value) return null;
-  return value.replace(/_(amount|returns|claims|count|total|collections|projected_amount)$/, "");
-}
-
-function breakdownFromSourceMeasure(
-  variable: string | null,
-  measureId: string | null,
-): string | null {
-  if (!variable || !measureId) return null;
-  const variablePrefix = variable.replace(/\s+/g, "_").toLowerCase();
-  const measure = measureId.toLowerCase();
-  if (!measure.startsWith(`${variablePrefix}_`)) return null;
-  const detail = measure
-    .slice(variablePrefix.length + 1)
-    .replace(/_(amount|returns|claims|count|total|collections|projected_amount)$/, "");
-  if (
-    variablePrefix === "eitc" &&
-    ["amount", "returns", "claims", "count", "total"].includes(detail)
-  ) {
-    return "all children";
-  }
-  if (
-    ["amount", "returns", "claims", "count", "total", "collections", "projected_amount"].includes(detail)
-  ) {
-    return null;
-  }
-  if (!detail || MEASURES.has(detail)) return null;
-  return readableToken(detail);
-}
-
-function qualifyingChildrenFromRecordSet(value: string | null): string | null {
-  if (!value) return null;
-  const match = /\.eitc_by_agi_children\.([^.]+)$/.exec(value);
-  if (!match) return null;
-  const childGroup = match[1];
-  if (childGroup === "no_qualifying_children") return "no qualifying children";
-  if (childGroup === "one_qualifying_child") return "one qualifying child";
-  if (childGroup === "two_qualifying_children") return "two qualifying children";
-  if (childGroup === "three_or_more_qualifying_children") {
-    return "three or more qualifying children";
-  }
-  return readableToken(childGroup);
-}
-
 function qualifyingChildrenFromCount(value: string | null): string | null {
   if (value == null) return null;
   if (value === "0") return "no qualifying children";
@@ -700,12 +628,6 @@ interface DecomposedTargetFilter {
   dimensions: TargetBreakdownDimension[];
 }
 
-interface DecomposedStructuredDimensions {
-  geography: string | null;
-  level: string | null;
-  dimensions: TargetBreakdownDimension[];
-}
-
 function dimensionValue(
   label: string,
   rawValue: string,
@@ -729,39 +651,6 @@ function filterDimensionValue(spec: FilterDimensionSpec, rawValue: string): stri
   return dimensionValue(spec.label, rawValue, spec.valueLabels);
 }
 
-function decomposeStructuredDimensions(
-  values: JsonObject,
-  definitions: Record<string, DiagnosticsDimension>,
-): DecomposedStructuredDimensions {
-  let geography: string | null = null;
-  let level: string | null = null;
-  const dimensions: TargetBreakdownDimension[] = [];
-  for (const [id, raw] of Object.entries(values)) {
-    const rawValue = stringValue(raw)?.trim();
-    if (!rawValue) continue;
-    const definition = definitions[id];
-    const label = definition?.label ?? dimensionLabel(id);
-    const value = dimensionValue(label, rawValue, definition?.values);
-    const rankOrder = definition?.order ??
-      (definition?.values ? Object.keys(definition.values) : undefined);
-    const rank = rankOrder?.indexOf(rawValue) ?? -1;
-    if (definition?.role === "geography") {
-      geography ??= value;
-      level ??= definition.level ?? "region";
-      continue;
-    }
-    dimensions.push({
-      key: dimensionKey(label),
-      label,
-      value,
-      source_key: id,
-      raw_value: rawValue,
-      ...(rank >= 0 ? { rank } : {}),
-    });
-  }
-  return { geography, level, dimensions };
-}
-
 function decomposeTargetFilter(value: unknown): DecomposedTargetFilter | null {
   const filter = stringValue(value);
   if (!filter) return null;
@@ -793,164 +682,6 @@ function decomposeTargetFilter(value: unknown): DecomposedTargetFilter | null {
   return null;
 }
 
-function chroniclePublisherFromMetadata(metadata: JsonObject): string | null {
-  if (!Array.isArray(metadata.chronicle_record_ids)) return null;
-  const first = metadata.chronicle_record_ids.find(
-    (value): value is string => typeof value === "string" && Boolean(value.trim()),
-  );
-  return first?.trim().split(".", 1)[0] || null;
-}
-
-interface StructuredTargetSource {
-  id: string | null;
-  citation: string | null;
-  label: string | null;
-  url: string | null;
-}
-
-interface StructuredTargetVariable {
-  id: string;
-  label: string | null;
-  measure: string | null;
-}
-
-function structuredTargetSource(value: unknown): StructuredTargetSource | null {
-  if (!isPlainObject(value)) return null;
-  return {
-    id: stringValue(value.id)?.trim() ?? null,
-    citation: stringValue(value.citation)?.trim() ?? null,
-    label: stringValue(value.label)?.trim() ?? null,
-    url: stringValue(value.url)?.trim() ?? null,
-  };
-}
-
-function structuredTargetVariable(value: unknown): StructuredTargetVariable | null {
-  if (!isPlainObject(value)) return null;
-  const id = stringValue(value.id)?.trim();
-  if (!id) return null;
-  return {
-    id,
-    label: stringValue(value.label)?.trim() ?? null,
-    measure: stringValue(value.measure)?.trim() ?? null,
-  };
-}
-
-function artifactVariable(
-  name: string,
-  row: TargetRow,
-  decomposition: DecomposedTargetFilter | null,
-  structuredVariable: StructuredTargetVariable | null,
-): string | null {
-  const metadata = asObject(row.metadata);
-  if (structuredVariable) return structuredVariable.id;
-  const published =
-    stringValue(metadata.variable) ??
-    (typeof row.variable === "string" ? stringValue(row.variable) : null);
-  if (published) return readableToken(published);
-  if (!name.includes("_") || name.includes("/")) return null;
-
-  let identifier = name;
-  const filter = decomposition ? stringValue(row.filter) : null;
-  const filterSuffix = filter?.replace(/^cell_/, "");
-  if (filterSuffix && identifier.endsWith(`_${filterSuffix}`)) {
-    identifier = identifier.slice(0, -(filterSuffix.length + 1));
-  }
-  const separator = identifier.indexOf("_");
-  if (separator >= 0) identifier = identifier.slice(separator + 1);
-  return readableToken(identifier);
-}
-
-function parseDottedTarget(
-  name: string,
-  row: TargetRow,
-  nationalGeography: string,
-): ParsedTarget | null {
-  if (!name.includes(".")) return null;
-  const metadata = asObject(row.metadata);
-  const registry = asObject(row.registry);
-  const parts = name.split(".");
-  const source = stringValue(registry.family) ?? parts[0] ?? "";
-  const geoLevel = stringValue(metadata.ledger_geography_level);
-  const geoId = stringValue(metadata.ledger_geography_id);
-  const geography =
-    geoLevel === "country"
-      ? nationalGeography
-      : geoLevel === "congressional_district"
-        ? districtFromGeoId(geoId) ?? ""
-        : stateFromGeoId(geoId) ?? stringValue(metadata.state) ?? "";
-  const level =
-    geoLevel === "country"
-      ? "national"
-      : geoLevel === "state"
-        ? "state"
-        : geoLevel === "congressional_district"
-          ? "congressional_district"
-          : "";
-  const measureId = stringValue(metadata.source_measure_id) ?? parts.at(-1) ?? "";
-  const variable =
-    readableToken(stringValue(metadata.variable)) ??
-    readableToken(variableFromMeasure(measureId)) ??
-    readableToken(parts.at(-2) ?? null) ??
-    "";
-  const childBreakdown = qualifyingChildrenFromRecordSet(
-    stringValue(metadata.ledger_layout_record_set_id),
-  );
-  const breakdown = [
-    readableToken(stringValue(metadata.ledger_layout_groupby_value_id)),
-    childBreakdown ?? breakdownFromSourceMeasure(variable, measureId),
-    readableToken(stringValue(metadata.filing_status)),
-  ]
-    .filter((value): value is string => Boolean(value && value !== variable))
-    .join(" · ");
-
-  return { geography, level, source, variable, breakdown };
-}
-
-function parseTarget(name: string, nationalGeography: string): ParsedTarget {
-  const parts = name.split("/");
-  const p0 = parts[0] ?? "";
-  const fips = /^US(\d{2})$/.exec(p0);
-  if (fips) {
-    return {
-      geography: FIPS_TO_ABBR[fips[1]] ?? p0,
-      level: "state",
-      source: "admin",
-      variable: parts[1] ?? "",
-      breakdown: parts.slice(2).join(" · "),
-    };
-  }
-  if (p0 === "state") {
-    const second = parts[1] ?? "";
-    if (STATE_ABBRS.has(second) && second !== "US") {
-      return {
-        geography: second, level: "state", source: "state",
-        variable: parts[2] ?? "", breakdown: parts.slice(3).join(" · "),
-      };
-    }
-    const last = parts[parts.length - 1];
-    if (parts.length >= 4 && STATE_ABBRS.has(last)) {
-      return {
-        geography: last, level: "state", source: parts[1] ?? "",
-        variable: parts[2] ?? "", breakdown: parts.slice(3, -1).join(" · "),
-      };
-    }
-    return {
-      geography: "state", level: "state", source: parts[1] ?? "",
-      variable: parts[2] ?? "", breakdown: parts.slice(3).join(" · "),
-    };
-  }
-  if (p0 === "nation" || p0 === "national" || p0 === "us") {
-    return {
-      geography: nationalGeography, level: "national", source: parts[1] ?? "",
-      variable: parts[2] ?? "", breakdown: parts.slice(3).join(" · "),
-    };
-  }
-  return {
-    geography: "", level: "", source: p0,
-    variable: parts[1] ?? "", breakdown: parts.slice(2).join(" · "),
-  };
-}
-
 function variableKeyOf(parsed: ParsedTarget): string {
   return [parsed.source, parsed.variable].filter(Boolean).join(" / ");
 }
@@ -1285,59 +1016,41 @@ function enrichTargetRow(
     initialError == null || finalError == null
       ? null
       : Math.abs(initialError) - Math.abs(finalError);
-  const publishedSource = structuredTargetSource(row.source);
-  const publishedVariable = structuredTargetVariable(row.variable);
-  const structuredDecomposition = isPlainObject(row.dimensions)
-    ? decomposeStructuredDimensions(row.dimensions, dimensionDefinitions)
+  const rowRepresentation = classifyTargetRow(row);
+  const structuredIdentity = rowRepresentation === "structured"
+    ? readStructuredTarget(row, dimensionDefinitions, nationalGeography)
     : null;
-  const filterDecomposition = structuredDecomposition
+  const filterDecomposition = structuredIdentity
     ? null
     : decomposeTargetFilter(row.filter);
-  const dimensionAdapter = structuredDecomposition
+  const dimensionAdapter = structuredIdentity
     ? "structured"
     : filterDecomposition
       ? "legacy_filter"
       : "legacy_name";
-  const publisher =
-    chroniclePublisherFromMetadata(metadata) ?? publishedSource?.id ?? null;
-  const parsedFromName =
-    parseDottedTarget(baseName, row, nationalGeography) ??
-    parseTarget(baseName, nationalGeography);
-  const parsed: ParsedTarget = {
-    ...parsedFromName,
-    geography:
-      structuredDecomposition?.geography ??
-      filterDecomposition?.geography ??
-      parsedFromName.geography,
-    level:
-      structuredDecomposition?.level ??
-      filterDecomposition?.level ??
-      parsedFromName.level,
-    source: publisher ?? parsedFromName.source,
-    variable:
-      artifactVariable(
+  const legacyParsed = structuredIdentity
+    ? null
+    : readLegacyTarget(
         baseName,
         row,
+        nationalGeography,
         filterDecomposition,
-        publishedVariable,
-      ) ??
-      parsedFromName.variable,
-    breakdown: structuredDecomposition
-      ? structuredDecomposition.dimensions
-          .map((dimension) => dimension.value)
-          .join(" · ")
-      : filterDecomposition
-        ? filterDecomposition.dimensions
-            .map((dimension) => dimension.value)
-            .join(" · ")
-        : parsedFromName.breakdown,
-  };
+      );
+  const parsed: ParsedTarget = structuredIdentity
+    ? {
+        geography: structuredIdentity.geography,
+        level: structuredIdentity.level,
+        source: structuredIdentity.source,
+        variable: structuredIdentity.variable,
+        breakdown: structuredIdentity.breakdown,
+      }
+    : legacyParsed!;
   const hasGeography = Boolean(parsed.geography.trim());
   const geography = hasGeography ? parsed.geography : nationalGeography;
   const level = hasGeography ? parsed.level : DEFAULT_GEOGRAPHY_LEVEL;
   const measureCol = asObject(row.measure);
   const metadataTargetDimensions =
-    structuredDecomposition?.dimensions ??
+    structuredIdentity?.dimensions ??
     filterDecomposition?.dimensions ??
     metadataDimensions(row);
   const targetDimensions =
@@ -1356,11 +1069,11 @@ function enrichTargetRow(
   // IRS variables publish both a total (dollar amount) and a count (number of
   // returns), so the measure is part of the variable's identity, not a
   // breakdown within it — fold it into variable_key so they're distinct things.
-  const measure =
-    publishedVariable?.measure ??
-    (dims[0] && MEASURES.has(dims[0])
+  const measure = structuredIdentity
+    ? structuredIdentity.measure
+    : dims[0] && MEASURES.has(dims[0])
       ? dims[0]
-      : measureFromMetadata(metadata));
+      : measureFromMetadata(metadata);
   const variableKey =
     variableKeyOf(parsed) + (measure ? ` · ${measure}` : "");
   // Underscore identifiers and filter-decomposed targets use the structured
@@ -1368,17 +1081,19 @@ function enrichTargetRow(
   // without filter dimensions retain their legacy family so US/UK releases do
   // not regroup merely because they also carry Chronicle record IDs.
   const usesArtifactFamily =
-    publishedSource?.id != null ||
-    publishedVariable != null ||
-    structuredDecomposition != null ||
+    structuredIdentity != null ||
     filterDecomposition != null ||
-    (publisher != null && !baseName.includes("/") && !baseName.includes("."));
+    (chroniclePublisherFromMetadata(metadata) != null &&
+      !baseName.includes("/") &&
+      !baseName.includes("."));
   return {
     ...row,
     name: fullName,
     base_name: baseName,
     family: deriveFamily(baseName, parsed, usesArtifactFamily),
-    state: stateFromGeoId(stringValue(metadata.ledger_geography_id)) ?? deriveState(baseName),
+    state: structuredIdentity
+      ? null
+      : stateFromGeoId(stringValue(metadata.ledger_geography_id)) ?? deriveState(baseName),
     geography,
     level,
     source: parsed.source,
@@ -1386,10 +1101,10 @@ function enrichTargetRow(
       (Object.hasOwn(publisherLabels, parsed.source)
         ? publisherLabels[parsed.source]
         : undefined) ??
-      publishedSource?.label ??
+      structuredIdentity?.sourceLabel ??
       sourceAuthorityLabel(parsed.source),
     variable: parsed.variable,
-    variable_label: publishedVariable?.label ?? null,
+    variable_label: structuredIdentity?.variableLabel ?? null,
     measure,
     target_role: targetRole,
     source_measure_id: sourceMeasureId,
@@ -1415,10 +1130,11 @@ function enrichTargetRow(
     variable_key: variableKey,
     // v2 published metadata (null on v1).
     source_citation:
-      typeof row.source === "string"
+      structuredIdentity?.sourceCitation ??
+      (typeof row.source === "string"
         ? (row.source as string)
-        : publishedSource?.citation ?? null,
-    source_url: publishedSource?.url ?? null,
+        : null),
+    source_url: structuredIdentity?.sourceUrl ?? null,
     entity: typeof row.entity === "string" ? (row.entity as string) : null,
     aggregation: typeof row.aggregation === "string" ? (row.aggregation as string) : null,
     measure_name: typeof measureCol.name === "string" ? (measureCol.name as string) : null,
@@ -1770,6 +1486,7 @@ export interface TreemapLeaf {
   key: string;
   source: string;
   variable: string;
+  label: string | null;
   measure: string | null;
   measure_counts: { measure: string | null; n_targets: number }[];
   filters: TreemapFilters;
@@ -1874,6 +1591,13 @@ export function microcosmTargetTreemap(
       .map((row) => numberOrNull(row.abs_relative_error))
       .filter((v): v is number => v != null && Number.isFinite(v));
     const first = group[0];
+    const variableLabels = [
+      ...new Set(
+        group
+          .map((row) => stringValue(row.variable_label)?.trim())
+          .filter((label): label is string => Boolean(label)),
+      ),
+    ];
     const filters: TreemapFilters =
       breakdown === "geography"
         ? { geography: key }
@@ -1885,6 +1609,10 @@ export function microcosmTargetTreemap(
         breakdown === "geography"
           ? key
           : String(first.variable ?? key),
+      label:
+        breakdown === "geography" || variableLabels.length !== 1
+          ? null
+          : variableLabels[0],
       measure: null,
       measure_counts: measureCounts(group),
       filters,
@@ -1953,6 +1681,7 @@ export function microcosmTargetTreemap(
 export interface TargetSchema {
   diagnostics_schema_version: number | null;
   structured_dimensions: boolean;
+  target_representation: TargetRepresentation;
 }
 
 export interface Calibration {
@@ -2209,6 +1938,7 @@ export function buildCalibration(
   const targets = (Array.isArray(diag.targets) ? (diag.targets as TargetRow[]) : []).map(
     normalizeDiagnosticsRow,
   );
+  const targetRepresentation = classifyTargetRepresentation(targets);
   const skipped = Array.isArray(diag.skipped) ? (diag.skipped as JsonObject[]) : [];
   const targetCompilation = asObject(asObject(buildManifest.gates).target_compilation);
   const droppedTargetNames = Array.isArray(targetCompilation.dropped_target_names)
@@ -2253,6 +1983,7 @@ export function buildCalibration(
     target_schema: {
       diagnostics_schema_version: numberOrNull(diag.schema_version),
       structured_dimensions: isPlainObject(diag.dimensions),
+      target_representation: targetRepresentation,
     },
     description:
       stringValue(diag.description) ??
@@ -2300,13 +2031,13 @@ export function hfResolveUrl(path: string, country: MicrocosmCountry = "us"): st
 
 // A hung HF request would otherwise block the function for the whole route
 // maxDuration and pin the shared in-flight cache promise; cap each fetch.
-const HF_FETCH_TIMEOUT_MS = 20_000;
+const MICROCOSM_RELEASE_FETCH_TIMEOUT_MS = 120_000;
 
 async function hfFetch(url: string, revalidate: number): Promise<Response> {
   return fetch(url, {
     next: { revalidate },
     headers: hfAuthHeaders(),
-    signal: AbortSignal.timeout(HF_FETCH_TIMEOUT_MS),
+    signal: AbortSignal.timeout(MICROCOSM_RELEASE_FETCH_TIMEOUT_MS),
   });
 }
 
diff --git a/frontend/lib/microcosm/legacy-target-reader.ts b/frontend/lib/microcosm/legacy-target-reader.ts
new file mode 100644
index 00000000..8d32441b
--- /dev/null
+++ b/frontend/lib/microcosm/legacy-target-reader.ts
@@ -0,0 +1,289 @@
+type JsonObject = Record<string, unknown>;
+
+export interface ParsedLegacyTarget {
+  geography: string;
+  level: string;
+  source: string;
+  variable: string;
+  breakdown: string;
+}
+
+export interface LegacyFilterDecomposition {
+  geography: string;
+  level: string;
+  dimensions: ReadonlyArray<{ value: string }>;
+}
+
+const FIPS_TO_ABBR: Record<string, string> = {
+  "01": "AL", "02": "AK", "04": "AZ", "05": "AR", "06": "CA", "08": "CO",
+  "09": "CT", "10": "DE", "11": "DC", "12": "FL", "13": "GA", "15": "HI",
+  "16": "ID", "17": "IL", "18": "IN", "19": "IA", "20": "KS", "21": "KY",
+  "22": "LA", "23": "ME", "24": "MD", "25": "MA", "26": "MI", "27": "MN",
+  "28": "MS", "29": "MO", "30": "MT", "31": "NE", "32": "NV", "33": "NH",
+  "34": "NJ", "35": "NM", "36": "NY", "37": "NC", "38": "ND", "39": "OH",
+  "40": "OK", "41": "OR", "42": "PA", "44": "RI", "45": "SC", "46": "SD",
+  "47": "TN", "48": "TX", "49": "UT", "50": "VT", "51": "VA", "53": "WA",
+  "54": "WV", "55": "WI", "56": "WY",
+};
+
+const STATE_ABBRS = new Set([
+  "AL", "AK", "AZ", "AR", "CA", "CO", "CT", "DE", "DC", "FL", "GA", "HI", "ID",
+  "IL", "IN", "IA", "KS", "KY", "LA", "ME", "MD", "MA", "MI", "MN", "MS", "MO",
+  "MT", "NE", "NV", "NH", "NJ", "NM", "NY", "NC", "ND", "OH", "OK", "OR", "PA",
+  "RI", "SC", "SD", "TN", "TX", "UT", "VT", "VA", "WA", "WV", "WI", "WY", "US",
+]);
+
+const MEASURES = new Set(["total", "count", "mean", "filers", "nonfilers"]);
+const LEGACY_UNDERSCORE_PUBLISHERS = new Set([
+  "statbel",
+  "onss",
+  "jrc",
+  "sfpd",
+  "nasa",
+]);
+
+function asObject(value: unknown): JsonObject {
+  return value != null && typeof value === "object" && !Array.isArray(value)
+    ? (value as JsonObject)
+    : {};
+}
+
+function stringValue(value: unknown): string | null {
+  return typeof value === "string" && value.trim() ? value : null;
+}
+
+function readableToken(value: string | null): string | null {
+  return value ? value.replace(/_/g, " ") : null;
+}
+
+export function stateFromGeoId(value: string | null): string | null {
+  if (!value) return null;
+  const match = /US(\d{2})$/.exec(value);
+  return match ? FIPS_TO_ABBR[match[1]] ?? null : null;
+}
+
+export function districtFromGeoId(value: string | null): string | null {
+  if (!value) return null;
+  const match = /US(\d{2})(\d{2})$/.exec(value);
+  if (!match) return null;
+  const state = FIPS_TO_ABBR[match[1]];
+  return state ? `${state}-${match[2]}` : null;
+}
+
+function variableFromMeasure(value: string | null): string | null {
+  return value
+    ? value.replace(/_(amount|returns|claims|count|total|collections|projected_amount)$/, "")
+    : null;
+}
+
+function breakdownFromSourceMeasure(
+  variable: string | null,
+  measureId: string | null,
+): string | null {
+  if (!variable || !measureId) return null;
+  const variablePrefix = variable.replace(/\s+/g, "_").toLowerCase();
+  const measure = measureId.toLowerCase();
+  if (!measure.startsWith(`${variablePrefix}_`)) return null;
+  const detail = measure
+    .slice(variablePrefix.length + 1)
+    .replace(/_(amount|returns|claims|count|total|collections|projected_amount)$/, "");
+  if (
+    variablePrefix === "eitc" &&
+    ["amount", "returns", "claims", "count", "total"].includes(detail)
+  ) {
+    return "all children";
+  }
+  if (
+    !detail ||
+    MEASURES.has(detail) ||
+    ["amount", "returns", "claims", "count", "total", "collections", "projected_amount"]
+      .includes(detail)
+  ) {
+    return null;
+  }
+  return readableToken(detail);
+}
+
+export function qualifyingChildrenFromRecordSet(value: string | null): string | null {
+  if (!value) return null;
+  const match = /\.eitc_by_agi_children\.([^.]+)$/.exec(value);
+  if (!match) return null;
+  const childGroup = match[1];
+  if (childGroup === "no_qualifying_children") return "no qualifying children";
+  if (childGroup === "one_qualifying_child") return "one qualifying child";
+  if (childGroup === "two_qualifying_children") return "two qualifying children";
+  if (childGroup === "three_or_more_qualifying_children") {
+    return "three or more qualifying children";
+  }
+  return readableToken(childGroup);
+}
+
+export function chroniclePublisherFromMetadata(metadata: JsonObject): string | null {
+  if (!Array.isArray(metadata.chronicle_record_ids)) return null;
+  const first = metadata.chronicle_record_ids.find(
+    (value): value is string => typeof value === "string" && Boolean(value.trim()),
+  );
+  return first?.trim().split(".", 1)[0] || null;
+}
+
+function legacyVariable(
+  name: string,
+  row: JsonObject,
+  decomposition: LegacyFilterDecomposition | null,
+): string | null {
+  const metadata = asObject(row.metadata);
+  const published =
+    stringValue(metadata.variable) ??
+    (typeof row.variable === "string" ? stringValue(row.variable) : null);
+  if (published) return readableToken(published);
+
+  if (decomposition && name.includes("_") && !name.includes("/")) {
+    let identifier = name;
+    const filterSuffix = stringValue(row.filter)?.replace(/^cell_/, "");
+    if (filterSuffix && identifier.endsWith(`_${filterSuffix}`)) {
+      identifier = identifier.slice(0, -(filterSuffix.length + 1));
+    }
+    const separator = identifier.indexOf("_");
+    if (separator >= 0) identifier = identifier.slice(separator + 1);
+    return readableToken(identifier);
+  }
+
+  const namePublisher = name.split("_", 1)[0];
+  if (LEGACY_UNDERSCORE_PUBLISHERS.has(namePublisher)) {
+    return readableToken(name.slice(namePublisher.length + 1));
+  }
+  const publisher = chroniclePublisherFromMetadata(metadata);
+  if (publisher && !name.includes(".") && name.startsWith(`${publisher}_`)) {
+    return readableToken(name.slice(publisher.length + 1));
+  }
+  return null;
+}
+
+function parseDottedTarget(
+  name: string,
+  row: JsonObject,
+  nationalGeography: string,
+): ParsedLegacyTarget | null {
+  if (!name.includes(".")) return null;
+  const metadata = asObject(row.metadata);
+  const registry = asObject(row.registry);
+  const parts = name.split(".");
+  const source = stringValue(registry.family) ?? parts[0] ?? "";
+  const geoLevel = stringValue(metadata.ledger_geography_level);
+  const geoId = stringValue(metadata.ledger_geography_id);
+  const geography =
+    geoLevel === "country"
+      ? nationalGeography
+      : geoLevel === "congressional_district"
+        ? districtFromGeoId(geoId) ?? ""
+        : stateFromGeoId(geoId) ?? stringValue(metadata.state) ?? "";
+  const level =
+    geoLevel === "country"
+      ? "national"
+      : geoLevel === "state"
+        ? "state"
+        : geoLevel === "congressional_district"
+          ? "congressional_district"
+          : "";
+  const measureId = stringValue(metadata.source_measure_id) ?? parts.at(-1) ?? "";
+  const variable =
+    readableToken(stringValue(metadata.variable)) ??
+    readableToken(variableFromMeasure(measureId)) ??
+    readableToken(parts.at(-2) ?? null) ??
+    "";
+  const childBreakdown = qualifyingChildrenFromRecordSet(
+    stringValue(metadata.ledger_layout_record_set_id),
+  );
+  const breakdown = [
+    readableToken(stringValue(metadata.ledger_layout_groupby_value_id)),
+    childBreakdown ?? breakdownFromSourceMeasure(variable, measureId),
+    readableToken(stringValue(metadata.filing_status)),
+  ]
+    .filter((value): value is string => Boolean(value && value !== variable))
+    .join(" · ");
+
+  return { geography, level, source, variable, breakdown };
+}
+
+function parseSlashTarget(name: string, nationalGeography: string): ParsedLegacyTarget {
+  const parts = name.split("/");
+  const p0 = parts[0] ?? "";
+  const fips = /^US(\d{2})$/.exec(p0);
+  if (fips) {
+    return {
+      geography: FIPS_TO_ABBR[fips[1]] ?? p0,
+      level: "state",
+      source: "admin",
+      variable: parts[1] ?? "",
+      breakdown: parts.slice(2).join(" · "),
+    };
+  }
+  if (p0 === "state") {
+    const second = parts[1] ?? "";
+    if (STATE_ABBRS.has(second) && second !== "US") {
+      return {
+        geography: second,
+        level: "state",
+        source: "state",
+        variable: parts[2] ?? "",
+        breakdown: parts.slice(3).join(" · "),
+      };
+    }
+    const last = parts[parts.length - 1];
+    if (parts.length >= 4 && STATE_ABBRS.has(last)) {
+      return {
+        geography: last,
+        level: "state",
+        source: parts[1] ?? "",
+        variable: parts[2] ?? "",
+        breakdown: parts.slice(3, -1).join(" · "),
+      };
+    }
+    return {
+      geography: "state",
+      level: "state",
+      source: parts[1] ?? "",
+      variable: parts[2] ?? "",
+      breakdown: parts.slice(3).join(" · "),
+    };
+  }
+  if (p0 === "nation" || p0 === "national" || p0 === "us") {
+    return {
+      geography: nationalGeography,
+      level: "national",
+      source: parts[1] ?? "",
+      variable: parts[2] ?? "",
+      breakdown: parts.slice(3).join(" · "),
+    };
+  }
+  return {
+    geography: "",
+    level: "",
+    source: p0,
+    variable: parts[1] ?? "",
+    breakdown: parts.slice(2).join(" · "),
+  };
+}
+
+export function readLegacyTarget(
+  name: string,
+  row: JsonObject,
+  nationalGeography: string,
+  decomposition: LegacyFilterDecomposition | null,
+): ParsedLegacyTarget {
+  const metadata = asObject(row.metadata);
+  const parsed =
+    parseDottedTarget(name, row, nationalGeography) ??
+    parseSlashTarget(name, nationalGeography);
+  const publisher = chroniclePublisherFromMetadata(metadata);
+  return {
+    ...parsed,
+    geography: decomposition?.geography ?? parsed.geography,
+    level: decomposition?.level ?? parsed.level,
+    source: publisher ?? parsed.source,
+    variable: legacyVariable(name, row, decomposition) ?? parsed.variable,
+    breakdown: decomposition
+      ? decomposition.dimensions.map((dimension) => dimension.value).join(" · ")
+      : parsed.breakdown,
+  };
+}
diff --git a/frontend/lib/microcosm/legacy-target-regression.test.ts b/frontend/lib/microcosm/legacy-target-regression.test.ts
new file mode 100644
index 00000000..c4d4fd3c
--- /dev/null
+++ b/frontend/lib/microcosm/legacy-target-regression.test.ts
@@ -0,0 +1,226 @@
+import { expect, test } from "bun:test";
+import { readFileSync } from "node:fs";
+import { gunzipSync } from "node:zlib";
+
+import { createExplorerState } from "./calibration-explorer";
+import { buildCalibrationTree } from "./calibration-tree";
+import { buildCalibration } from "./latest-artifact";
+
+const RELEASE_ID =
+  "populace-us-2024-buildp-sparse-rmloss100-cae8640-20260728T011454Z";
+
+function legacyIdentityFixture(): Record<string, unknown> {
+  const compressed = readFileSync(
+    new URL("./fixtures/us-legacy-target-identities.json.gz", import.meta.url),
+  );
+  return JSON.parse(gunzipSync(compressed).toString("utf8"));
+}
+
+function normalizedIdentity(row: Record<string, unknown>) {
+  const dimensions = Array.isArray(row.target_dimensions)
+    ? row.target_dimensions.map((value) => {
+        const dimension = value as Record<string, unknown>;
+        return {
+          key: dimension.key,
+          label: dimension.label,
+          value: dimension.value,
+        };
+      })
+    : [];
+
+  return {
+    name: row.name,
+    family: row.family,
+    source: row.source,
+    variable: row.variable,
+    variable_key: row.variable_key,
+    geography: row.geography,
+    level: row.level,
+    state: row.state,
+    measure: row.measure,
+    breakdown: row.breakdown,
+    dimension_adapter: row.dimension_adapter,
+    dimensions,
+  };
+}
+
+test("the pinned US release retains its legacy source and statistic grouping", () => {
+  const calibration = buildCalibration(legacyIdentityFixture(), RELEASE_ID);
+  const tree = buildCalibrationTree(calibration.rows, createExplorerState());
+  const nodeCounts = Object.fromEntries(
+    tree.groups.map((group) => [group.id, group.nodes.length]),
+  );
+
+  expect(calibration.target_schema.target_representation).toBe("legacy");
+  expect(calibration.rows).toHaveLength(5_659);
+  expect(tree.groups).toHaveLength(15);
+  expect(Object.values(nodeCounts).reduce((sum, count) => sum + count, 0)).toBe(53);
+  expect(nodeCounts).toEqual({
+    irs_soi: 33,
+    census_population: 1,
+    cms_medicaid: 3,
+    ssa: 2,
+    usda_snap: 2,
+    cms_aca: 2,
+    state_income_tax: 1,
+    hhs_acf_tanf: 1,
+    jct: 1,
+    cbo: 1,
+    bea: 2,
+    cms_medicare: 1,
+    federal_reserve: 1,
+    hhs_acf_liheap: 1,
+    unspecified: 1,
+  });
+  expect(tree.groups.find((group) => group.id === "bea")?.nodes.map((node) => node.label))
+    .toEqual(["Amount", "Wages salaries"]);
+});
+
+test("the pinned US release retains representative normalized target identities", () => {
+  const calibration = buildCalibration(legacyIdentityFixture(), RELEASE_ID);
+  const rowsByName = new Map(
+    calibration.rows.map((row) => [String(row.name), row]),
+  );
+  const names = [
+    "irs_soi.ty2024.filing_season_week47.eitc_all_returns.earned_income_credit.total_earned_income_credit_returns@2024",
+    "irs_soi.ty2022.historic_table_2.state_agi.al.1_to_10k.taxable_interest_returns@2024",
+    "census_pep.cy2024.national_resident_population_age.0_to_4.population@2024",
+    "cms_medicaid.month2024_12.state_enrollment.ak.total_medicaid_chip_enrollment@2024",
+    "ssa_supplement.cy2024.oasdi_ssi_payments.social_security_benefits.payment_amount@2024",
+    "census_stc.fy2023.individual_income_tax_collections.al.t40.collections@2024",
+    "bea_nipa.cy2023.proprietors_income.a041rc.amount@2024",
+    "selection_mass_protection.keogh_distributions@0",
+  ];
+  const identities = names.map((name) => {
+    const row = rowsByName.get(name);
+    if (!row) throw new Error(`Pinned legacy fixture is missing ${name}`);
+    return normalizedIdentity(row);
+  });
+
+  expect(identities).toEqual([
+    {
+      name: names[0],
+      family:
+        "irs_soi.ty2024.filing_season_week47.eitc_all_returns.earned_income_credit.total_earned_income_credit_returns",
+      source: "irs_soi",
+      variable: "eitc",
+      variable_key: "irs_soi / eitc · count",
+      geography: "United States",
+      level: "national",
+      state: null,
+      measure: "count",
+      breakdown: "earned income credit · All",
+      dimension_adapter: "legacy_name",
+      dimensions: [
+        { key: "bd_breakdown", label: "Breakdown", value: "earned income credit" },
+        { key: "bd_filing_status", label: "Filing status", value: "All" },
+      ],
+    },
+    {
+      name: names[1],
+      family:
+        "irs_soi.ty2022.historic_table_2.state_agi.al.1_to_10k.taxable_interest_returns",
+      source: "irs_soi",
+      variable: "taxable interest income",
+      variable_key: "irs_soi / taxable interest income · count",
+      geography: "AL",
+      level: "state",
+      state: "AL",
+      measure: "count",
+      breakdown: "1 to 10k · All",
+      dimension_adapter: "legacy_name",
+      dimensions: [
+        { key: "bd_breakdown", label: "Breakdown", value: "1 to 10k" },
+        { key: "bd_filing_status", label: "Filing status", value: "All" },
+      ],
+    },
+    {
+      name: names[2],
+      family: "census_pep.cy2024.national_resident_population_age.0_to_4.population",
+      source: "census_population",
+      variable: "population",
+      variable_key: "census_population / population",
+      geography: "United States",
+      level: "national",
+      state: null,
+      measure: null,
+      breakdown: "0 to 4",
+      dimension_adapter: "legacy_name",
+      dimensions: [{ key: "bd_breakdown", label: "Breakdown", value: "0 to 4" }],
+    },
+    {
+      name: names[3],
+      family:
+        "cms_medicaid.month2024_12.state_enrollment.ak.total_medicaid_chip_enrollment",
+      source: "cms_medicaid",
+      variable: "total medicaid chip enrollment",
+      variable_key: "cms_medicaid / total medicaid chip enrollment",
+      geography: "AK",
+      level: "state",
+      state: "AK",
+      measure: null,
+      breakdown: "",
+      dimension_adapter: "legacy_name",
+      dimensions: [],
+    },
+    {
+      name: names[4],
+      family:
+        "ssa_supplement.cy2024.oasdi_ssi_payments.social_security_benefits.payment_amount",
+      source: "ssa",
+      variable: "payment",
+      variable_key: "ssa / payment · total",
+      geography: "United States",
+      level: "national",
+      state: null,
+      measure: "total",
+      breakdown: "social security benefits",
+      dimension_adapter: "legacy_name",
+      dimensions: [
+        { key: "bd_breakdown", label: "Breakdown", value: "social security benefits" },
+      ],
+    },
+    {
+      name: names[5],
+      family: "census_stc.fy2023.individual_income_tax_collections.al.t40.collections",
+      source: "state_income_tax",
+      variable: "collections",
+      variable_key: "state_income_tax / collections",
+      geography: "AL",
+      level: "state",
+      state: "AL",
+      measure: null,
+      breakdown: "t40",
+      dimension_adapter: "legacy_name",
+      dimensions: [{ key: "bd_breakdown", label: "Breakdown", value: "t40" }],
+    },
+    {
+      name: names[6],
+      family: "bea_nipa.cy2023.proprietors_income.a041rc.amount",
+      source: "bea",
+      variable: "amount",
+      variable_key: "bea / amount",
+      geography: "United States",
+      level: "national",
+      state: null,
+      measure: null,
+      breakdown: "a041rc",
+      dimension_adapter: "legacy_name",
+      dimensions: [{ key: "bd_breakdown", label: "Breakdown", value: "a041rc" }],
+    },
+    {
+      name: names[7],
+      family: "selection_mass_protection.keogh_distributions",
+      source: "unspecified",
+      variable: "keogh distributions",
+      variable_key: "unspecified / keogh distributions",
+      geography: "United States",
+      level: "national",
+      state: null,
+      measure: null,
+      breakdown: "",
+      dimension_adapter: "legacy_name",
+      dimensions: [],
+    },
+  ]);
+});
diff --git a/frontend/lib/microcosm/presentation.test.ts b/frontend/lib/microcosm/presentation.test.ts
index 31b402e6..34e4c403 100644
--- a/frontend/lib/microcosm/presentation.test.ts
+++ b/frontend/lib/microcosm/presentation.test.ts
@@ -14,7 +14,7 @@ test("artifact presentation takes precedence over legacy country copy", () => {
 
 test("legacy presentation copy remains the fallback for existing countries", () => {
   expect(microcosmOverviewIntro("us")).toBe(
-    "Microcosm reweights survey microdata so it matches official statistics from agencies like the IRS, the Census Bureau, and CMS. Each tile in the Calibration fit explorer below is a category we calibrate to, including EITC statistics, population, and Medicaid enrollment.",
+    "Microcosm reweights survey microdata so it matches official statistics from agencies like the IRS, the Census Bureau, and CMS. Each of these official statistics is a calibration target, grouped by category in the calibration fit explorer below.",
   );
   expect(microcosmTargetsIntro("us")).toBe(
     "Pick a measure like EITC, population, or AGI and see how each breakdown is calibrated.",
@@ -23,7 +23,7 @@ test("legacy presentation copy remains the fallback for existing countries", ()
 
 test("unpublished countries receive the generic presentation copy", () => {
   expect(microcosmOverviewIntro("zz")).toBe(
-    "Microcosm reweights survey microdata so it matches official statistics from national statistical agencies and administrative sources. Each tile in the Calibration fit explorer below is a category we calibrate to.",
+    "Microcosm reweights survey microdata so it matches official statistics from national statistical agencies and administrative sources. Each of these official statistics is a calibration target, grouped by category in the calibration fit explorer below.",
   );
   expect(microcosmTargetsIntro("zz")).toBe(
     "Pick a measure and see how each breakdown is calibrated.",
diff --git a/frontend/lib/microcosm/presentation.ts b/frontend/lib/microcosm/presentation.ts
index 5e674f6f..d74c78bf 100644
--- a/frontend/lib/microcosm/presentation.ts
+++ b/frontend/lib/microcosm/presentation.ts
@@ -8,24 +8,21 @@ export interface MicrocosmPresentationSlots {
 // Legacy copy for releases published before `release_manifest.presentation`;
 // delete once US/UK/BE publish the block.
 const LEGACY_OVERVIEW_COPY: Partial<
-  Record<MicrocosmCountry, { authorities: string; examples: string }>
+  Record<MicrocosmCountry, { authorities: string }>
 > = {
   us: {
     authorities: "the IRS, the Census Bureau, and CMS",
-    examples: "EITC statistics, population, and Medicaid enrollment",
   },
   uk: {
     authorities: "the ONS, OBR, and HMRC",
-    examples: "population by region and age, household types, and tax receipts",
   },
   be: {
     authorities: "Statbel, ONSS, JRC, and SFPD",
-    examples: "population by region, sex, and age band, tax receipts, and benefit totals",
   },
 };
 
 const GENERIC_OVERVIEW_INTRO =
-  "Microcosm reweights survey microdata so it matches official statistics from national statistical agencies and administrative sources. Each tile in the Calibration fit explorer below is a category we calibrate to.";
+  "Microcosm reweights survey microdata so it matches official statistics from national statistical agencies and administrative sources. Each of these official statistics is a calibration target, grouped by category in the calibration fit explorer below.";
 
 // Legacy copy for releases published before `release_manifest.presentation`;
 // delete once US/UK/BE publish the block.
@@ -48,7 +45,7 @@ export function microcosmOverviewIntro(
   if (presentation?.overview_intro) return presentation.overview_intro;
   const legacy = LEGACY_OVERVIEW_COPY[country];
   return legacy
-    ? `Microcosm reweights survey microdata so it matches official statistics from agencies like ${legacy.authorities}. Each tile in the Calibration fit explorer below is a category we calibrate to, including ${legacy.examples}.`
+    ? `Microcosm reweights survey microdata so it matches official statistics from agencies like ${legacy.authorities}. Each of these official statistics is a calibration target, grouped by category in the calibration fit explorer below.`
     : GENERIC_OVERVIEW_INTRO;
 }
 
diff --git a/frontend/lib/microcosm/structured-dimension-reader.test.ts b/frontend/lib/microcosm/structured-dimension-reader.test.ts
new file mode 100644
index 00000000..6777b8d9
--- /dev/null
+++ b/frontend/lib/microcosm/structured-dimension-reader.test.ts
@@ -0,0 +1,31 @@
+import { expect, test } from "bun:test";
+
+import {
+  readStructuredDimensions,
+  structuredDimensionKey,
+} from "./structured-dimension-reader";
+
+test("structured dimension keys derive from ids rather than display labels", () => {
+  const result = readStructuredDimensions(
+    { origin: "north", destination: "east" },
+    {
+      origin: { label: "Region", values: { north: "North" } },
+      destination: { label: "Region", values: { east: "East" } },
+    },
+  );
+
+  expect(result.dimensions).toEqual([
+    expect.objectContaining({ key: "bd_origin", label: "Region", value: "North" }),
+    expect.objectContaining({ key: "bd_destination", label: "Region", value: "East" }),
+  ]);
+});
+
+test("punctuated and reserved ids receive distinct query-safe keys", () => {
+  const punctuated = structuredDimensionKey("us:statutes/26/62#income");
+  const reserved = structuredDimensionKey("x0_7573");
+
+  expect(punctuated).toMatch(/^bd_[a-z0-9_]+$/);
+  expect(reserved).toMatch(/^bd_[a-z0-9_]+$/);
+  expect(punctuated).not.toBe(reserved);
+  expect(structuredDimensionKey("age_band")).toBe("bd_age_band");
+});
diff --git a/frontend/lib/microcosm/structured-dimension-reader.ts b/frontend/lib/microcosm/structured-dimension-reader.ts
new file mode 100644
index 00000000..6ca60d87
--- /dev/null
+++ b/frontend/lib/microcosm/structured-dimension-reader.ts
@@ -0,0 +1,116 @@
+type JsonObject = Record<string, unknown>;
+
+export interface StructuredDimensionDefinition {
+  label: string;
+  role?: "geography";
+  level?: string;
+  values?: Record<string, string>;
+  order?: string[];
+}
+
+export interface StructuredTargetDimension {
+  key: string;
+  label: string;
+  value: string;
+  source_key: string;
+  raw_value: string;
+  rank?: number;
+}
+
+export interface StructuredDimensions {
+  geography: string | null;
+  level: string | null;
+  dimensions: StructuredTargetDimension[];
+}
+
+function stringValue(value: unknown): string | null {
+  return typeof value === "string" && value.trim() ? value.trim() : null;
+}
+
+function titleCase(value: string): string {
+  return value
+    .replace(/[_:./#-]+/g, " ")
+    .replace(/\s+/g, " ")
+    .trim()
+    .replace(/\b\w/g, (char) => char.toUpperCase());
+}
+
+function dimensionLabel(value: string): string {
+  if (value === "us:statutes/26/62#adjusted_gross_income") return "Income band";
+  if (value === "census_stc.item") return "Item";
+  if (value === "hhs_acf_tanf.spending_category") return "Spending category";
+  if (value.startsWith("cms_medicaid.")) {
+    return titleCase(value.replace(/^cms_medicaid\./, ""));
+  }
+  const hash = value.split("#").at(-1);
+  const last = hash?.split(".").at(-1) ?? value;
+  return titleCase(last);
+}
+
+function utf8Hex(value: string): string {
+  return [...new TextEncoder().encode(value)]
+    .map((byte) => byte.toString(16).padStart(2, "0"))
+    .join("");
+}
+
+// Simple lowercase identifiers retain their established keys. Identifiers
+// containing punctuation, uppercase characters, or the reserved escape prefix
+// use an injective UTF-8 encoding that remains safe in facet query parameters.
+export function structuredDimensionKey(id: string): string {
+  if (/^[a-z0-9_]+$/.test(id) && !id.startsWith("x0_")) return `bd_${id}`;
+  return `bd_x0_${utf8Hex(id)}`;
+}
+
+function dimensionValue(
+  label: string,
+  rawValue: string,
+  valueLabels?: Readonly<Record<string, string>>,
+): string {
+  const explicit = valueLabels && Object.hasOwn(valueLabels, rawValue)
+    ? valueLabels[rawValue]
+    : undefined;
+  if (explicit) return explicit;
+  if (label.toLowerCase() === "age band") {
+    const range = /^(\d+)_(\d+)$/.exec(rawValue);
+    if (range) return `${range[1]}–${range[2]}`;
+    const openEnded = /^(\d+)_plus$/.exec(rawValue);
+    if (openEnded) return `${openEnded[1]}+`;
+  }
+  return titleCase(rawValue);
+}
+
+export function readStructuredDimensions(
+  values: JsonObject,
+  definitions: Record<string, StructuredDimensionDefinition>,
+): StructuredDimensions {
+  let geography: string | null = null;
+  let level: string | null = null;
+  const dimensions: StructuredTargetDimension[] = [];
+
+  for (const [id, raw] of Object.entries(values)) {
+    if (!id) continue;
+    const rawValue = stringValue(raw);
+    if (!rawValue) continue;
+    const definition = definitions[id];
+    const label = definition?.label ?? dimensionLabel(id);
+    const value = dimensionValue(label, rawValue, definition?.values);
+    const rankOrder = definition?.order ??
+      (definition?.values ? Object.keys(definition.values) : undefined);
+    const rank = rankOrder?.indexOf(rawValue) ?? -1;
+    if (definition?.role === "geography") {
+      geography ??= value;
+      level ??= definition.level ?? "region";
+      continue;
+    }
+    dimensions.push({
+      key: structuredDimensionKey(id),
+      label,
+      value,
+      source_key: id,
+      raw_value: rawValue,
+      ...(rank >= 0 ? { rank } : {}),
+    });
+  }
+
+  return { geography, level, dimensions };
+}
diff --git a/frontend/lib/microcosm/structured-target-reader.ts b/frontend/lib/microcosm/structured-target-reader.ts
new file mode 100644
index 00000000..3213d784
--- /dev/null
+++ b/frontend/lib/microcosm/structured-target-reader.ts
@@ -0,0 +1,61 @@
+import {
+  readStructuredDimensions,
+  type StructuredDimensionDefinition,
+  type StructuredTargetDimension,
+} from "./structured-dimension-reader";
+
+type JsonObject = Record<string, unknown>;
+
+export interface StructuredTargetIdentity {
+  source: string;
+  sourceLabel: string | null;
+  sourceCitation: string | null;
+  sourceUrl: string | null;
+  variable: string;
+  variableLabel: string | null;
+  measure: string | null;
+  geography: string;
+  level: string;
+  dimensions: StructuredTargetDimension[];
+  breakdown: string;
+}
+
+function isPlainObject(value: unknown): value is JsonObject {
+  if (!value || typeof value !== "object" || Array.isArray(value)) return false;
+  const prototype = Object.getPrototypeOf(value);
+  return prototype === Object.prototype || prototype === null;
+}
+
+function stringValue(value: unknown): string | null {
+  return typeof value === "string" && value.trim() ? value.trim() : null;
+}
+
+export function readStructuredTarget(
+  row: JsonObject,
+  definitions: Record<string, StructuredDimensionDefinition>,
+  nationalGeography: string,
+): StructuredTargetIdentity {
+  const source = isPlainObject(row.source) ? row.source : {};
+  const variable = isPlainObject(row.variable) ? row.variable : {};
+  const values = isPlainObject(row.dimensions) ? row.dimensions : {};
+  const sourceId = stringValue(source.id) ?? "other";
+  const variableId = stringValue(variable.id) ?? "unknown";
+  const structured = readStructuredDimensions(values, definitions);
+  const geography = structured.geography ?? nationalGeography;
+  const level = structured.level ?? "national";
+  const { dimensions } = structured;
+
+  return {
+    source: sourceId,
+    sourceLabel: stringValue(source.label),
+    sourceCitation: stringValue(source.citation),
+    sourceUrl: stringValue(source.url),
+    variable: variableId,
+    variableLabel: stringValue(variable.label),
+    measure: stringValue(variable.measure),
+    geography,
+    level,
+    dimensions,
+    breakdown: dimensions.map((dimension) => dimension.value).join(" · "),
+  };
+}
diff --git a/frontend/lib/microcosm/target-representation.test.ts b/frontend/lib/microcosm/target-representation.test.ts
new file mode 100644
index 00000000..a72c482b
--- /dev/null
+++ b/frontend/lib/microcosm/target-representation.test.ts
@@ -0,0 +1,57 @@
+import { describe, expect, test } from "bun:test";
+
+import {
+  classifyTargetRow,
+  classifyTargetRepresentation,
+  isCompleteStructuredTarget,
+  isLegacyTarget,
+} from "./target-representation";
+
+const structured = {
+  source: { id: "novastat" },
+  variable: { id: "population" },
+  dimensions: {},
+};
+
+describe("calibration target representation", () => {
+  test("reports unknown when there are no target rows", () => {
+    expect(classifyTargetRepresentation([])).toBe("unknown");
+  });
+
+  test("classifies rows without structured identity fields as legacy", () => {
+    const rows = [
+      { name: "irs.population.total", source: "IRS SOI" },
+      { name: "state/ca/population", variable: "population" },
+    ];
+    expect(rows.every(isLegacyTarget)).toBe(true);
+    expect(classifyTargetRepresentation(rows)).toBe("legacy");
+  });
+
+  test("requires complete structured identity on every structured row", () => {
+    expect(isCompleteStructuredTarget(structured)).toBe(true);
+    expect(isCompleteStructuredTarget({ ...structured, dimensions: undefined })).toBe(false);
+    expect(isCompleteStructuredTarget({ ...structured, source: { label: "Nova" } })).toBe(false);
+    expect(isCompleteStructuredTarget({ ...structured, variable: { id: " " } })).toBe(false);
+  });
+
+  test("classifies complete structured rows independently of diagnostics schema", () => {
+    expect(classifyTargetRepresentation([
+      { ...structured, schema_version: 5 },
+      { ...structured, schema_version: 6 },
+    ])).toBe("structured");
+  });
+
+  test("classifies a collection containing complete structured and legacy rows as mixed", () => {
+    expect(classifyTargetRepresentation([
+      structured,
+      { name: "irs.population.total", source: "IRS SOI" },
+    ])).toBe("mixed");
+  });
+
+  test("rejects partially structured rows", () => {
+    expect(() => classifyTargetRow({
+      source: { id: "novastat" },
+      variable: "population",
+    })).toThrow("complete structured identity fields or legacy fields");
+  });
+});
diff --git a/frontend/lib/microcosm/target-representation.ts b/frontend/lib/microcosm/target-representation.ts
new file mode 100644
index 00000000..1bd041d6
--- /dev/null
+++ b/frontend/lib/microcosm/target-representation.ts
@@ -0,0 +1,47 @@
+export type TargetRepresentation = "legacy" | "structured" | "mixed" | "unknown";
+export type TargetRowRepresentation = "legacy" | "structured";
+
+type JsonObject = Record<string, unknown>;
+
+function isPlainObject(value: unknown): value is JsonObject {
+  return value != null && typeof value === "object" && !Array.isArray(value);
+}
+
+function nonEmptyString(value: unknown): value is string {
+  return typeof value === "string" && value.trim().length > 0;
+}
+
+export function isCompleteStructuredTarget(row: JsonObject): boolean {
+  return (
+    isPlainObject(row.source) &&
+    nonEmptyString(row.source.id) &&
+    isPlainObject(row.variable) &&
+    nonEmptyString(row.variable.id) &&
+    isPlainObject(row.dimensions)
+  );
+}
+
+export function isLegacyTarget(row: JsonObject): boolean {
+  return (
+    !isPlainObject(row.source) &&
+    !isPlainObject(row.variable) &&
+    !isPlainObject(row.dimensions)
+  );
+}
+
+export function classifyTargetRow(row: JsonObject): TargetRowRepresentation {
+  if (isCompleteStructuredTarget(row)) return "structured";
+  if (isLegacyTarget(row)) return "legacy";
+  throw new Error(
+    "Calibration target rows must use either complete structured identity fields or legacy fields.",
+  );
+}
+
+export function classifyTargetRepresentation(
+  rows: readonly JsonObject[],
+): TargetRepresentation {
+  if (rows.length === 0) return "unknown";
+  const representations = new Set(rows.map(classifyTargetRow));
+  if (representations.size > 1) return "mixed";
+  return representations.has("structured") ? "structured" : "legacy";
+}
diff --git a/frontend/lib/microcosm/third-country-conformance.test.ts b/frontend/lib/microcosm/third-country-conformance.test.ts
index 6acc972b..422b79f1 100644
--- a/frontend/lib/microcosm/third-country-conformance.test.ts
+++ b/frontend/lib/microcosm/third-country-conformance.test.ts
@@ -202,7 +202,7 @@ describe("synthetic third-country conformance", () => {
       navGroupsForCountry(COUNTRY)
         .flatMap((group) => group.items)
         .map((item) => item.href),
-    ).toEqual(["/microcosm", "/microcosm/targets", "/microcosm/compare"]);
+    ).toEqual(["/microcosm", "/microcosm/compare"]);
   });
   test(
     "zz overview data can carry artifact-provided intro copy: the summary omits a typed presentation contract",
@@ -280,7 +280,13 @@ describe("synthetic third-country conformance", () => {
         },
         targets: diagnosticsFixture.targets.map((target, index) =>
           index < facetValues.length
-            ? { ...target, filter: null, dimensions: facetValues[index] }
+            ? {
+                ...target,
+                source: { id: PUBLISHER, citation: "ZZ official population table" },
+                variable: { id: "population", measure: "count" },
+                filter: null,
+                dimensions: facetValues[index],
+              }
             : target,
         ),
       };
@@ -335,16 +341,14 @@ describe("synthetic third-country conformance", () => {
         );
         return {
           ...target,
-          ...(index === 0
+          filter: index === 0 ? null : target.filter,
+          dimensions: index === 0
             ? {
-                filter: null,
-                dimensions: {
-                  region: "north",
-                  sex: "female",
-                  age_band: "0_17",
-                },
+                region: "north",
+                sex: "female",
+                age_band: "0_17",
               }
-            : {}),
+            : {},
           source: structuredSource,
           variable: structuredVariable,
           metadata,
@@ -361,12 +365,8 @@ describe("synthetic third-country conformance", () => {
       COUNTRY,
     );
 
-    expect(futureCalibration.rows.map((row) => row.dimension_adapter)).toEqual([
-      "structured",
-      "legacy_filter",
-      "legacy_filter",
-      "legacy_name",
-    ]);
+    expect(futureCalibration.rows.every((row) => row.dimension_adapter === "structured"))
+      .toBe(true);
     const page = latestMicrocosmTargetDiagnosticsPage(
       `http://x/api/microcosm/target-diagnostics?variable=${encodeURIComponent("novastat_agency / population · count")}`,
       futureCalibration,