BreadcrumbList builder

Creates breadcrumbs and assigns one-based positions automatically. The BreadcrumbList builder injects @type, validates synchronously, and rejects unknown properties.

Import

// Astro — shown first when Astro is selected
import { BreadcrumbList } from '@unschema-graph/astro';

// Svelte 5
import { BreadcrumbList } from '@unschema-graph/svelte';

// Core / Node.js
import { BreadcrumbList } from '@unschema-graph/core';
import { BreadcrumbListSchema } from '@unschema-graph/core';

The BreadcrumbListSchema Zod schema is also exported for composition and advanced validation.

TypeScript types

import {
  BreadcrumbListSchema,
  type SchemaInput,
  type SchemaOutput,
} from '@unschema-graph/core';

type BreadcrumbListInput = SchemaInput<typeof BreadcrumbListSchema>;
type BreadcrumbListOutput = SchemaOutput<typeof BreadcrumbListSchema, 'BreadcrumbList'>;

Input properties

Property	Input type	Required	Default / constraints
@id	string	No	non-empty
itemListElement	Array	Yes	—

The aliases above remain the exact authority for nested object types. The builder also accepts a validation configuration as its second argument and always returns @type: 'BreadcrumbList'.

Minimal example

import { BreadcrumbList } from '@unschema-graph/core';

const entity = BreadcrumbList({
  "itemListElement": [
    {
      "name": "Home",
      "item": "/"
    },
    {
      "name": "Guides",
      "item": "/guides/"
    },
    {
      "name": "Current page"
    }
  ]
});

Output

{
  "@type": "BreadcrumbList",
  "itemListElement": [
    {
      "@type": "ListItem",
      "position": 1,
      "name": "Home",
      "item": "/"
    },
    {
      "@type": "ListItem",
      "position": 2,
      "name": "Guides",
      "item": "/guides/"
    },
    {
      "@type": "ListItem",
      "position": 3,
      "name": "Current page"
    }
  ]
}

Relationships and recipes

• Related builders: Article, BlogPosting, NewsArticle, Recipe
• Used by: Blog & media
• External sources: Schema.org BreadcrumbList · Google Search Central

Common errors

• Passing an unknown property to the strict builder.
• Using source data that is missing a required property.
• Assuming valid Schema.org guarantees a search appearance.

Validation

Use BreadcrumbList.safeParse(input) for external data. If Schema.org supports a property that is not modeled yet, validate the entity first and then use withAdditionalProperties(). Never pass invented properties to the strict builder.