Add label, defaultValue, and unique attributes to schema fields

Extend the Field interface with optional label, defaultValue, and unique
properties to support richer form rendering and database constraints.
Update all consumers for consistency: schema dialog UI, form page,
SQL generation, schema validation, JSON Schema output, and table
introspection.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: bchapuis

apps/api/src/routes/forms.ts

@@ -7,6 +7,7 @@
  */
 
 import { verifyFormToken } from "@dafthunk/runtime";
+import type { Field } from "@dafthunk/types";
 import { Hono } from "hono";
 
 import type { ApiContext } from "../context";
@@ -42,7 +43,7 @@ formRoutes.get("/:signedToken", async (c) => {
     const parsed = JSON.parse(schema) as {
       title: string;
       description?: string;
-      fields: Array<{ name: string; type: string; required?: boolean }>;
+      fields: Field[];
     };
 
     return c.json({

apps/app/src/components/schema-dialog.tsx

@@ -1,4 +1,6 @@
 import type { Field, FieldType, SchemaEntity } from "@dafthunk/types";
+import Asterisk from "lucide-react/icons/asterisk";
+import Hash from "lucide-react/icons/hash";
 import KeyRound from "lucide-react/icons/key-round";
 import PlusCircle from "lucide-react/icons/plus-circle";
 import Trash2 from "lucide-react/icons/trash-2";
@@ -22,7 +24,6 @@ import {
   SelectValue,
 } from "@/components/ui/select";
 import { Spinner } from "@/components/ui/spinner";
-import { Switch } from "@/components/ui/switch";
 import { Textarea } from "@/components/ui/textarea";
 import {
   Tooltip,
@@ -88,18 +89,43 @@ function FieldEditor({ fields, onChange }: FieldEditorProps) {
         return (
           <div key={index} className="flex items-center gap-2">
             <Input
-              placeholder="Field name"
+              placeholder="Name"
               value={field.name}
-              onChange={(e) => updateField(index, { name: e.target.value })}
-              className={cn("flex-1", isDuplicate && "border-destructive")}
+              onChange={(e) =>
+                updateField(index, { name: e.target.value })
+              }
+              className={cn(
+                "flex-1 min-w-0",
+                isDuplicate && "border-destructive"
+              )}
+            />
+            <Input
+              placeholder="Label"
+              value={field.label ?? ""}
+              onChange={(e) =>
+                updateField(index, {
+                  label: e.target.value || undefined,
+                })
+              }
+              className="flex-1 min-w-0"
+            />
+            <Input
+              placeholder="Default value"
+              value={field.defaultValue ?? ""}
+              onChange={(e) =>
+                updateField(index, {
+                  defaultValue: e.target.value || undefined,
+                })
+              }
+              className="flex-1 min-w-0"
             />
             <Select
               value={field.type}
               onValueChange={(val) =>
                 updateField(index, { type: val as FieldType })
               }
             >
-              <SelectTrigger className="w-32">
+              <SelectTrigger className="w-28">
                 <SelectValue />
               </SelectTrigger>
               <SelectContent>
@@ -110,18 +136,6 @@ function FieldEditor({ fields, onChange }: FieldEditorProps) {
                 ))}
               </SelectContent>
             </Select>
-            <div className="flex items-center gap-1">
-              <Switch
-                checked={field.required ?? false}
-                onCheckedChange={(checked) =>
-                  updateField(index, {
-                    required: checked ? true : undefined,
-                  })
-                }
-                className="scale-75"
-              />
-              <span className="text-xs text-muted-foreground">Req</span>
-            </div>
             <TooltipProvider>
               <Tooltip>
                 <TooltipTrigger asChild>
@@ -137,7 +151,8 @@ function FieldEditor({ fields, onChange }: FieldEditorProps) {
                         onChange(
                           fields.map((f, i) => ({
                             ...f,
-                            primaryKey: i === index ? true : undefined,
+                            primaryKey:
+                              i === index ? true : undefined,
                           }))
                         );
                       }
@@ -160,6 +175,69 @@ function FieldEditor({ fields, onChange }: FieldEditorProps) {
                 </TooltipContent>
               </Tooltip>
             </TooltipProvider>
+            <TooltipProvider>
+              <Tooltip>
+                <TooltipTrigger asChild>
+                  <Button
+                    type="button"
+                    variant={field.unique ? "secondary" : "ghost"}
+                    size="icon"
+                    className="h-8 w-8 shrink-0"
+                    disabled={field.primaryKey}
+                    onClick={() =>
+                      updateField(index, {
+                        unique: field.unique ? undefined : true,
+                      })
+                    }
+                  >
+                    <Hash
+                      className={cn(
+                        "h-4 w-4",
+                        field.unique
+                          ? "text-foreground"
+                          : "text-muted-foreground"
+                      )}
+                    />
+                  </Button>
+                </TooltipTrigger>
+                <TooltipContent>
+                  {field.unique
+                    ? "Remove unique constraint"
+                    : "Set as unique"}
+                </TooltipContent>
+              </Tooltip>
+            </TooltipProvider>
+            <TooltipProvider>
+              <Tooltip>
+                <TooltipTrigger asChild>
+                  <Button
+                    type="button"
+                    variant={field.required ? "secondary" : "ghost"}
+                    size="icon"
+                    className="h-8 w-8 shrink-0"
+                    onClick={() =>
+                      updateField(index, {
+                        required: field.required ? undefined : true,
+                      })
+                    }
+                  >
+                    <Asterisk
+                      className={cn(
+                        "h-4 w-4",
+                        field.required
+                          ? "text-foreground"
+                          : "text-muted-foreground"
+                      )}
+                    />
+                  </Button>
+                </TooltipTrigger>
+                <TooltipContent>
+                  {field.required
+                    ? "Set as optional"
+                    : "Set as required"}
+                </TooltipContent>
+              </Tooltip>
+            </TooltipProvider>
             <Button
               type="button"
               variant="ghost"
@@ -232,7 +310,7 @@ export function SchemaDialog({
 
   return (
     <Dialog open={open} onOpenChange={onOpenChange}>
-      <DialogContent className="sm:max-w-lg">
+      <DialogContent className="sm:max-w-5xl max-h-[85vh] overflow-y-auto">
         <DialogHeader>
           <DialogTitle>{title}</DialogTitle>
         </DialogHeader>

apps/app/src/pages/form-page.tsx

@@ -24,6 +24,8 @@ interface SchemaField {
   name: string;
   type: string;
   required?: boolean;
+  label?: string;
+  defaultValue?: string;
 }
 
 interface FormConfig {
@@ -54,6 +56,8 @@ function SchemaFieldInput({
   onChange: (value: unknown) => void;
   disabled: boolean;
 }) {
+  const displayLabel = field.label || field.name;
+
   switch (field.type) {
     case "boolean":
       return (
@@ -64,7 +68,7 @@ function SchemaFieldInput({
             onCheckedChange={onChange}
             disabled={disabled}
           />
-          <Label htmlFor={field.name}>{field.name}</Label>
+          <Label htmlFor={field.name}>{displayLabel}</Label>
         </div>
       );
 
@@ -73,7 +77,7 @@ function SchemaFieldInput({
       return (
         <div className="space-y-2">
           <Label htmlFor={field.name}>
-            {field.name}
+            {displayLabel}
             {field.required && <span className="text-destructive"> *</span>}
           </Label>
           <Input
@@ -100,7 +104,7 @@ function SchemaFieldInput({
       return (
         <div className="space-y-2">
           <Label htmlFor={field.name}>
-            {field.name}
+            {displayLabel}
             {field.required && <span className="text-destructive"> *</span>}
           </Label>
           <Input
@@ -117,7 +121,7 @@ function SchemaFieldInput({
       return (
         <div className="space-y-2">
           <Label htmlFor={field.name}>
-            {field.name}
+            {displayLabel}
             {field.required && <span className="text-destructive"> *</span>}
           </Label>
           <Textarea
@@ -136,7 +140,7 @@ function SchemaFieldInput({
       return (
         <div className="space-y-2">
           <Label htmlFor={field.name}>
-            {field.name}
+            {displayLabel}
             {field.required && <span className="text-destructive"> *</span>}
           </Label>
           <Input
@@ -183,6 +187,13 @@ export function FormPage() {
         if (config.submitted) {
           setState({ status: "already_submitted" });
         } else {
+          const defaults: Record<string, unknown> = {};
+          for (const f of config.fields) {
+            if (f.defaultValue !== undefined) {
+              defaults[f.name] = f.defaultValue;
+            }
+          }
+          setValues(defaults);
           setState({ status: "ready", config });
         }
       })

packages/runtime/src/nodes/database/database-describe-table-node.ts

@@ -85,10 +85,44 @@ export class DatabaseDescribeTableNode extends ExecutableNode {
       // Map schema results to Field format
       // PRAGMA table_info returns: cid, name, type, notnull, dflt_value, pk
       const rows = schemaResult.results as unknown as PragmaTableInfoRow[];
+
+      // Collect unique columns from single-column unique indexes
+      const uniqueColumns = new Set<string>();
+      try {
+        const indexList = await connection.query(
+          `PRAGMA index_list(${table})`
+        );
+        if (indexList.results) {
+          for (const idx of indexList.results as unknown as Array<{
+            name: string;
+            unique: number;
+          }>) {
+            if (!idx.unique) continue;
+            const indexInfo = await connection.query(
+              `PRAGMA index_info(${idx.name})`
+            );
+            if (
+              indexInfo.results &&
+              indexInfo.results.length === 1
+            ) {
+              const col = indexInfo.results[0] as unknown as {
+                name: string;
+              };
+              uniqueColumns.add(col.name);
+            }
+          }
+        }
+      } catch {
+        // PRAGMA index_list may not be available; proceed without unique info
+      }
+
       const fields: Field[] = rows.map((col) => ({
         name: col.name,
         type: mapSqliteToType(col.type || "TEXT"),
         ...(col.pk ? { primaryKey: true } : {}),
+        ...(!col.pk && uniqueColumns.has(col.name)
+          ? { unique: true }
+          : {}),
       }));
 
       const schema: Schema = {

packages/runtime/src/utils/database-table.ts

@@ -114,7 +114,8 @@ export function generateCreateTableSQL(schema: Schema): string {
   const columns = fields.map((field) => {
     const sqlType = mapTypeToSqlite(field.type);
     const pk = field.primaryKey ? " PRIMARY KEY" : "";
-    return `${field.name} ${sqlType}${pk}`;
+    const uq = !field.primaryKey && field.unique ? " UNIQUE" : "";
+    return `${field.name} ${sqlType}${pk}${uq}`;
   });
 
   return `CREATE TABLE IF NOT EXISTS ${name} (${columns.join(", ")})`;

packages/runtime/src/utils/schema-to-json-schema.ts

@@ -27,6 +27,12 @@ export function schemaToJsonSchema(schema: Schema): Record<string, unknown> {
     if (field.type === "datetime") {
       prop.format = "date-time";
     }
+    if (field.label) {
+      prop.description = field.label;
+    }
+    if (field.defaultValue !== undefined) {
+      prop.default = field.defaultValue;
+    }
     properties[field.name] = prop;
     if (field.required) {
       required.push(field.name);

packages/runtime/src/utils/schema-validation.ts

@@ -150,6 +150,12 @@ function validateField(
   const value = record[field.name];
 
   if (value === null || value === undefined) {
+    if (field.defaultValue !== undefined) {
+      const coerced = coerceValue(field.defaultValue, field.type);
+      if (coerced.ok) {
+        return { value: coerced.value, error: null };
+      }
+    }
     if (field.required) {
       return { value: null, error: `Missing required field '${field.name}'` };
     }

packages/types/src/types.ts

@@ -26,6 +26,9 @@ export interface Field {
   type: FieldType;
   required?: boolean;
   primaryKey?: boolean;
+  label?: string;
+  defaultValue?: string;
+  unique?: boolean;
 }
 
 /**