feat(ui): every export-target refusal reads as prose

frontend/ui-core/src/data/refusals.ts

@@ -154,6 +154,10 @@ export const REFUSAL_PROSE: Record<string, string> = {
   LOSSY_EXPORT_NOT_CONSENTED: "This target cannot take every shape in the dataset.",
   EXPORT_FORMAT_NOT_FOUND: "No exporter for that format is installed on this server.",
   EXPORT_TARGET_NOT_FOUND: "No installed exporter writes for that model.",
+  EXPORT_TARGET_CONFLICT:
+    "Two installed export plugins claim that model's name — remove one of them before exporting.",
+  INVALID_EXPORT_TARGET:
+    "An installed export plugin declares a model it cannot write for — check the installed export plugins.",
   UNSERIALIZABLE_MANIFEST: "This release's manifest cannot be read back — the workspace may be damaged.",
   EMPTY_RELEASE: "This dataset has no frames yet — promote a completed batch first.",
   // The dialog lists the classes beside this, from the refusal's own `blockers`.

frontend/ui-core/src/index.ts

@@ -445,7 +445,10 @@ export { useExportTargets, type ExportTarget } from "./screens/queries.js";
 export {
   ExportTargetSelect,
   exportTargetMeta,
+  EXPORT_TARGET_FAMILIES,
+  exportTargetFamily,
   groupExportTargets,
+  type ExportTargetFamily,
   type ExportTargetGroup,
   type ExportTargetSelectProps,
 } from "./patterns/ExportTargetSelect.js";

frontend/ui-core/src/patterns/ExportTargetSelect.tsx

@@ -27,11 +27,30 @@ import {
 } from "../primitives/Select";
 import type { ExportTarget } from "../screens/queries";
 
-const FAMILY_HEADINGS: readonly (readonly [family: string, heading: string])[] = [
-  ["ultralytics-yolo", "Ultralytics YOLO"],
-  ["community-yolo", "Community YOLO"],
+export interface ExportTargetFamily {
+  readonly family: string;
+  /** Over a group of targets, in the select. */
+  readonly heading: string;
+  /** Beside one target, inline. */
+  readonly word: string;
+}
+
+/**
+ * The families this build names, in reading order. The last row is the
+ * catch-all: a family the wire declares and no row names reads under it.
+ */
+export const EXPORT_TARGET_FAMILIES: readonly ExportTargetFamily[] = [
+  { family: "ultralytics-yolo", heading: "Ultralytics YOLO", word: "Ultralytics YOLO" },
+  { family: "community-yolo", heading: "Community YOLO", word: "Community YOLO" },
+  { family: "other", heading: "Other formats", word: "Other format" },
 ];
-const OTHER_HEADING = "Other formats";
+
+export function exportTargetFamily(family: string): ExportTargetFamily {
+  return (
+    EXPORT_TARGET_FAMILIES.find((one) => one.family === family) ??
+    EXPORT_TARGET_FAMILIES[EXPORT_TARGET_FAMILIES.length - 1]!
+  );
+}
 
 export interface ExportTargetGroup {
   readonly heading: string;
@@ -40,13 +59,10 @@ export interface ExportTargetGroup {
 
 /** The catalog under its headings, in heading order, groups with nothing omitted. */
 export function groupExportTargets(targets: readonly ExportTarget[]): readonly ExportTargetGroup[] {
-  const known = new Set(FAMILY_HEADINGS.map(([family]) => family));
-  const groups = FAMILY_HEADINGS.map(([family, heading]) => ({
-    heading,
-    targets: targets.filter((one) => one.family === family),
-  }));
-  groups.push({ heading: OTHER_HEADING, targets: targets.filter((one) => !known.has(one.family)) });
-  return groups.filter((group) => group.targets.length > 0);
+  return EXPORT_TARGET_FAMILIES.map((row) => ({
+    heading: row.heading,
+    targets: targets.filter((one) => exportTargetFamily(one.family) === row),
+  })).filter((group) => group.targets.length > 0);
 }
 
 /** The option's second line, or nothing when the target declares neither tasks nor geometries. */

frontend/ui-core/src/patterns/RecipeEditor.tsx

@@ -36,7 +36,7 @@ import {
   type RecipeDraft,
   type ResizeChoice,
 } from "../screens/recipeDraft";
-import { ExportTargetSelect } from "./ExportTargetSelect";
+import { ExportTargetSelect, exportTargetFamily } from "./ExportTargetSelect";
 import { StepMarker, type StepState } from "./StepMarker";
 
 const STRATEGIES: readonly { readonly value: ResizeChoice; readonly label: string }[] = [
@@ -418,17 +418,11 @@ function SizeField({
 
 /** `Ultralytics YOLO · detect, segment · data.yaml (ultralytics)` */
 export function targetSubtitle(target: ExportTarget): string {
-  const family = FAMILY_WORDS[target.family] ?? target.family;
+  const family = exportTargetFamily(target.family).word;
   const tasks = target.tasks.length === 0 ? "no task vocabulary" : target.tasks.join(", ");
   return `${family} · ${tasks} · writes ${target.format}`;
 }
 
-const FAMILY_WORDS: Record<string, string> = {
-  "ultralytics-yolo": "Ultralytics YOLO",
-  "community-yolo": "Community YOLO",
-  other: "Other format",
-};
-
 /** `Carries boxes and polygons · 12 classes` */
 export function targetCarries(target: ExportTarget, classCount: number | undefined): string {
   const words = target.geometries.map(

frontend/ui-core/src/screens/dataset.test.tsx

@@ -1300,4 +1300,27 @@ describe("export, and the recipe beside the target", () => {
     expect(said).toContain("cannot follow a polyline");
     expect(said).not.toContain("PREPROCESSING_STEP_UNSUPPORTED_GEOMETRY");
   });
+
+  // The two 500s a misdeclared export plugin raises. Neither is a rule the
+  // person broke, so the sentence has to say where the problem is.
+  it.each([
+    ["EXPORT_TARGET_CONFLICT", "two export plugins declare target 'dummy'", "Two installed export plugins"],
+    ["INVALID_EXPORT_TARGET", "target 'dummy' claims geometry 'polyline'", "cannot write for"],
+  ])("renders %s as prose", async (code, message, expected) => {
+    baseline();
+    handlers.push((request) =>
+      request.method === "POST" && request.url.includes("/export")
+        ? { status: 500, body: { code, message } }
+        : undefined,
+    );
+    render(mount(<DatasetScreen projectId={PROJECT} tab="releases" />));
+    await userEvent.click(await screen.findByTestId("export-v1"));
+    await userEvent.click(screen.getByTestId("export-target"));
+    await userEvent.click(await screen.findByRole("option", { name: /dummy/ }));
+    await userEvent.click(screen.getByTestId("export-submit"));
+
+    const said = (await screen.findByTestId("export-error")).textContent ?? "";
+    expect(said).toContain(expected);
+    expect(document.body.textContent).not.toContain(code);
+  });
 });