NVIDIA-NeMo · steramae-nvidia · Jul 15, 2026 · Jul 14, 2026 · Jul 15, 2026
@@ -12,19 +12,22 @@ import type { FC } from 'react';
 interface ColumnTypeCardProps {
   option: ColumnTypeOption;
   onSelect: (selection: AddColumnSelection) => void;
+  disabledReason?: string;
 }
 
 /**
  * A single column-type option, rendered as a {@link SelectableCard} so it is reachable and
  * activatable by keyboard (Tab to focus, Enter/Space to add) with no drag interaction.
  */
-export const ColumnTypeCard: FC<ColumnTypeCardProps> = ({ option, onSelect }) => {
+export const ColumnTypeCard: FC<ColumnTypeCardProps> = ({ option, onSelect, disabledReason }) => {
   const { icon: Icon, label, description, color, columnType, samplerType } = option;
   return (
     <SelectableCard
       className="w-full"
       title={label}
       subtitle={description}
+      disabled={Boolean(disabledReason)}
+      disabledReason={disabledReason}
       onActivate={() => onSelect({ columnType, samplerType })}
       leading={
         <CardIconBadge>

@@ -14,13 +14,16 @@ interface ColumnTypeGroupSectionProps {
   group: ColumnTypeGroup;
   options: ColumnTypeOption[];
   onSelect: (selection: AddColumnSelection) => void;
+  /** Disabled reasons keyed by column type; a set entry disables that option's card. */
+  disabledReasons?: Partial<Record<string, string>>;
 }
 
 /** A labeled group heading (with a count) above its option cards. */
 export const ColumnTypeGroupSection: FC<ColumnTypeGroupSectionProps> = ({
   group,
   options,
   onSelect,
+  disabledReasons,
 }) => (
   <Stack gap="1" className="w-full">
     <Flex align="center" gap="density-xs">
@@ -30,7 +33,12 @@ export const ColumnTypeGroupSection: FC<ColumnTypeGroupSectionProps> = ({
     </Flex>
     <Stack gap="1.5" className="w-full">
       {options.map((option) => (
-        <ColumnTypeCard key={option.id} option={option} onSelect={onSelect} />
+        <ColumnTypeCard
+          key={option.id}
+          option={option}
+          onSelect={onSelect}
+          disabledReason={option.columnType ? disabledReasons?.[option.columnType] : undefined}
+        />
       ))}
     </Stack>
   </Stack>

@@ -18,6 +18,11 @@ const matchesQuery = (option: ColumnTypeOption, query: string): boolean =>
 export interface AddColumnPaletteProps {
   /** Called with the chosen column type when an option is activated. */
   onAddColumn?: (selection: AddColumnSelection) => void;
+  /**
+   * Disabled reasons keyed by column type. An option whose column type has an entry renders as a
+   * disabled card with the reason as its tooltip — e.g. `{ 'seed-dataset': 'Only one…' }`.
+   */
+  disabledReasons?: Partial<Record<string, string>>;
   className?: string;
 }
 
@@ -30,7 +35,11 @@ export interface AddColumnPaletteProps {
  * presentational: wire {@link AddColumnPaletteProps.onAddColumn} to append a column to
  * the recipe.
  */
-export const AddColumnPalette: FC<AddColumnPaletteProps> = ({ onAddColumn, className }) => {
+export const AddColumnPalette: FC<AddColumnPaletteProps> = ({
+  onAddColumn,
+  disabledReasons,
+  className,
+}) => {
   const [search, setSearch] = useState('');
 
   const handleSelect = (selection: AddColumnSelection) => onAddColumn?.(selection);
@@ -76,6 +85,7 @@ export const AddColumnPalette: FC<AddColumnPaletteProps> = ({ onAddColumn, class
               group={group}
               options={options}
               onSelect={handleSelect}
+              disabledReasons={disabledReasons}
             />
           ))
         )}

@@ -0,0 +1,189 @@
+// SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+import { getPartsFromReference } from '@nemo/common/src/namedEntity';
+import { useFilesListFilesetFiles } from '@nemo/sdk/generated/platform/api';
+import { Flex, FormField, Select, Tag, Text } from '@nvidia/foundations-react-core';
+import { useDatasetFileContent } from '@studio/api/datasets/useDatasetFileContent';
+import { useWorkspaceFromPath } from '@studio/hooks/useWorkspaceFromPath';
+import {
+  SAMPLING_STRATEGY_OPTIONS,
+  SEED_AVAILABLE_COLUMNS_KEY,
+  SEED_FILE_PATH_KEY,
+  SEED_FILESET_REF_KEY,
+  SEED_SAMPLING_STRATEGY_KEY,
+} from '@studio/routes/DataDesignerJobBuildRoute/columns';
+import { FilesetSearchableSelect } from '@studio/routes/DeploymentsListRoute/CreateDeploymentSidePanel/FilesetSearchableSelect';
+import { getContentColumns, getFileExtension } from '@studio/util/files';
+import { type FC, useEffect, useMemo } from 'react';
+import { useForm } from 'react-hook-form';
+
+export interface SeedDatasetConfigProps {
+  /** The seed-dataset column's current field values. */
+  values: Record<string, string>;
+  /** Merges the given keys into the column's values (parent spreads onto the rest). */
+  onPatch: (patch: Record<string, string>) => void;
+}
+
+interface SeedFilesetForm {
+  [SEED_FILESET_REF_KEY]: string;
+}
+
+/**
+ * Config controls for a seed-dataset column, sourced from a platform fileset.
+ *
+ * The SDK's `FilesetFileSeedSource` takes a single composite `path`
+ * (`{workspace}/{fileset}#{file}`); rather than have the user hand-type that, this collects the
+ * fileset and the in-fileset file as separate picks (stored under {@link SEED_FILESET_REF_KEY} /
+ * {@link SEED_FILE_PATH_KEY}). `buildSeedConfig` assembles them into the composite path at submit.
+ *
+ * The fileset uses {@link FilesetSearchableSelect} for server-side `$like` search + paging. It is
+ * react-hook-form based, so a local form holds its value and pushes changes up via `onPatch`.
+ * The panel keys this component by column id, so each column mounts a form seeded from its values.
+ */
+export const SeedDatasetConfig: FC<SeedDatasetConfigProps> = ({ values, onPatch }) => {
+  const workspace = useWorkspaceFromPath();
+  const filesetRef = values[SEED_FILESET_REF_KEY] ?? '';
+  const filePath = values[SEED_FILE_PATH_KEY] ?? '';
+  const samplingStrategy = values[SEED_SAMPLING_STRATEGY_KEY] ?? '';
+
+  const { control, watch } = useForm<SeedFilesetForm>({
+    defaultValues: { [SEED_FILESET_REF_KEY]: filesetRef },
+  });
+
+  useEffect(() => {
+    const subscription = watch((formValues, { name }) => {
+      if (name !== SEED_FILESET_REF_KEY) return;
+      onPatch({
+        [SEED_FILESET_REF_KEY]: formValues[SEED_FILESET_REF_KEY] ?? '',
+        [SEED_FILE_PATH_KEY]: '',
+        [SEED_AVAILABLE_COLUMNS_KEY]: '',
+      });
+    });
+    return () => subscription.unsubscribe();
+  }, [watch, onPatch]);
+
+  const { workspace: filesetWorkspace, name: filesetName } = getPartsFromReference(filesetRef);
+  const { data: filesResponse, isLoading: isLoadingFiles } = useFilesListFilesetFiles(
+    filesetWorkspace,
+    filesetName,
+    undefined,
+    { query: { enabled: Boolean(filesetRef) } }
+  );
+  const fileItems = useMemo(
+    () => (filesResponse?.data ?? []).map((file) => ({ children: file.path, value: file.path })),
+    [filesResponse?.data]
+  );
+
+  const isParquet = filePath.endsWith('parquet');
+  const {
+    data: fileContent,
+    isLoading: isLoadingSchema,
+    isError: isSchemaError,
+  } = useDatasetFileContent({
+    workspace: filesetWorkspace,
+    name: filesetName,
+    path: filePath,
+    range: isParquet ? [0, 1] : undefined,
+    enabled: Boolean(filesetRef && filePath),
+  });
+  const availableColumns = useMemo(() => {
+    if (!fileContent) return [];
+    const fileType = isParquet ? 'jsonl' : (getFileExtension(filePath) ?? undefined);
+    return getContentColumns(fileContent, fileType);
+  }, [fileContent, filePath, isParquet]);
+
+  useEffect(() => {
+    const joined = availableColumns.join(',');
+    if ((values[SEED_AVAILABLE_COLUMNS_KEY] ?? '') !== joined) {
+      onPatch({ [SEED_AVAILABLE_COLUMNS_KEY]: joined });
+    }
+  }, [availableColumns, values, onPatch]);
+
+  const samplingItems = SAMPLING_STRATEGY_OPTIONS.map((option) => ({
+    children: option.label,
+    value: option.value,
+  }));
+
+  return (
+    <>
+      <FilesetSearchableSelect
+        workspace={workspace}
+        useControllerProps={{ control, name: SEED_FILESET_REF_KEY }}
+        formFieldProps={{
+          slotLabel: 'Fileset',
+          slotInfo: 'The platform fileset to seed rows from.',
+        }}
+        triggerPlaceholder="Select a fileset"
+      />
+
+      <FormField
+        slotLabel="File"
+        required
+        slotInfo="The file within the fileset to read rows from."
+      >
+        <Select
+          aria-label="Seed file"
+          disabled={!filesetRef}
+          items={fileItems}
+          value={filePath || undefined}
+          onValueChange={(value) =>
+            onPatch({
+              [SEED_FILE_PATH_KEY]: value ?? '',
+              [SEED_AVAILABLE_COLUMNS_KEY]: '',
+            })
+          }
+          placeholder={
+            !filesetRef
+              ? 'Select a fileset first'
+              : isLoadingFiles
+                ? 'Loading files…'
+                : 'Select a file'
+          }
+        />
+      </FormField>
+
+      {filePath && (
+        <FormField
+          slotLabel="Available columns"
+          slotInfo="Columns provided by the seed file. Reference them from other columns with {{ name }}."
+        >
+          {isLoadingSchema ? (
+            <Text kind="body/regular/sm" className="text-secondary">
+              Reading columns…
+            </Text>
+          ) : isSchemaError ? (
+            <Text kind="body/regular/sm" className="text-feedback-danger">
+              Couldn't read columns from this file.
+            </Text>
+          ) : availableColumns.length === 0 ? (
+            <Text kind="body/regular/sm" className="text-secondary">
+              No columns found in this file.
+            </Text>
+          ) : (
+            <Flex gap="density-xs" className="flex-wrap">
+              {availableColumns.map((name) => (
+                <Tag key={name} kind="outline" color="gray" readOnly>
+                  {name}
+                </Tag>
+              ))}
+            </Flex>
+          )}
+        </FormField>
+      )}
+
+      <FormField
+        slotLabel="Sampling strategy"
+        slotInfo="How rows are read from the seed dataset. Defaults to ordered."
+      >
+        <Select
+          aria-label="Sampling strategy"
+          items={samplingItems}
+          value={samplingStrategy || undefined}
+          onValueChange={(value) => onPatch({ [SEED_SAMPLING_STRATEGY_KEY]: value ?? '' })}
+          placeholder="Ordered"
+        />
+      </FormField>
+    </>
+  );
+};
@@ -19,6 +19,7 @@ import {
   TextInput,
 } from '@nvidia/foundations-react-core';
 import { ICON_COLOR_CLASS } from '@studio/components/AddColumnPalette/constants';
+import { SeedDatasetConfig } from '@studio/components/ColumnConfigPanel/SeedDatasetConfig';
 import { CardIconBadge } from '@studio/components/common/SelectableCard';
 import {
   type BuilderColumn,
@@ -209,14 +210,22 @@ export const ColumnConfigPanel: FC<ColumnConfigPanelProps> = ({
           />
         </FormField>
 
-        {fields.map((field) => (
-          <FieldControl
-            key={field.key}
-            field={field}
-            value={values[field.key] ?? ''}
-            onChange={(value) => setValue(field.key, value)}
+        {option.columnType === 'seed-dataset' ? (
+          <SeedDatasetConfig
+            key={column.id}
+            values={values}
+            onPatch={(patch) => onChange({ values: { ...values, ...patch } })}
           />
-        ))}
+        ) : (
+          fields.map((field) => (
+            <FieldControl
+              key={field.key}
+              field={field}
+              value={values[field.key] ?? ''}
+              onChange={(value) => setValue(field.key, value)}
+            />
+          ))
+        )}
       </Stack>
 
       <Flex align="center" justify="start" className="shrink-0 border-t border-base p-density-lg">

@@ -2,7 +2,10 @@
 // SPDX-License-Identifier: Apache-2.0
 
 import { parseFilesetUrl } from '@nemo/common/src/components/DatasetFileSelect/utils';
-import { parseCSV, parseFileContent } from '@studio/components/SafeSynthesizerFilesetPreview/util';
+import {
+  parseCSVTable,
+  parseFileContent,
+} from '@studio/components/SafeSynthesizerFilesetPreview/util';
 
 vi.mock('papaparse', () => ({
   default: {
@@ -39,7 +42,7 @@ describe('SafeSynthesizerDatasetPreview utils', () => {
 
       mockPapaParse.mockImplementation(vi.fn().mockReturnValue(mockParsedData));
 
-      const result = parseCSV(mockCsvContent);
+      const result = parseCSVTable(mockCsvContent);
 
       expect(mockPapaParse).toHaveBeenCalledWith(mockCsvContent, { header: true });
       expect(result.columns).toEqual([
@@ -71,7 +74,7 @@ describe('SafeSynthesizerDatasetPreview utils', () => {
 
       mockPapaParse.mockImplementation(vi.fn().mockReturnValue(mockParsedData));
 
-      const result = parseCSV('id,name\ncustom-id,John');
+      const result = parseCSVTable('id,name\ncustom-id,John');
 
       expect(result.rows[0].id).toBe('custom-id');
     });
@@ -92,7 +95,7 @@ describe('SafeSynthesizerDatasetPreview utils', () => {
 
       mockPapaParse.mockImplementation(vi.fn().mockReturnValue(mockParsedData));
 
-      const result = parseCSV('name\nJohn\nJane');
+      const result = parseCSVTable('name\nJohn\nJane');
 
       expect(result.rows[0].id).toBe('0');
       expect(result.rows[1].id).toBe('1');
@@ -114,7 +117,7 @@ describe('SafeSynthesizerDatasetPreview utils', () => {
 
       mockPapaParse.mockImplementation(vi.fn().mockReturnValue(mockParsedData));
 
-      const result = parseCSV('name,age,city\nJohn,,');
+      const result = parseCSVTable('name,age,city\nJohn,,');
 
       expect(result.rows[0].cells[1].children).toBe('');
       expect(result.rows[0].cells[2].children).toBe('');

@@ -4,7 +4,12 @@
 import Papa from 'papaparse';
 import { ReactNode } from 'react';
 
-export const parseCSV = (response: string) => {
+export interface ParsedCSVTable {
+  rows: { id: string; cells: { children: ReactNode }[] }[];
+  columns: { children: string }[];
+}
+
+export const parseCSVTable = (response: string): ParsedCSVTable => {
   const csvData = Papa.parse(response, { header: true });
   const rawRows = csvData.data as Record<string, unknown>[];
   const columnNames = csvData.meta.fields || [];
@@ -28,10 +33,7 @@ export const parseCSV = (response: string) => {
 export interface ParsedFileContent {
   type: 'json' | 'csv' | 'error';
   jsonData?: string;
-  tabularData?: {
-    rows: { id: string; cells: { children: ReactNode }[] }[];
-    columns: { children: string }[];
-  };
+  tabularData?: ParsedCSVTable;
   error?: string;
 }
 
@@ -43,7 +45,7 @@ export interface ParsedFileContent {
  */
 export const parseFileContent = (filePath: string, content: string): ParsedFileContent => {
   if (filePath.endsWith('.csv')) {
-    const csvData = parseCSV(content);
+    const csvData = parseCSVTable(content);
     return { type: 'csv', tabularData: csvData };
   }
   if (filePath.endsWith('.json') || filePath.endsWith('.jsonl')) {