Package Exports

@localess/client

Readme

Localess JavaScript / TypeScript Client SDK

The @localess/client package is the core JavaScript/TypeScript SDK for the Localess headless CMS platform. It provides a type-safe API client for fetching content, translations, and assets, along with Visual Editor integration utilities.

⚠️ Security Notice: This SDK is designed for server-side use only. It requires a Localess API Token that must be kept secret. Never use this package in browser/client-side code, as it would expose your API token to the public. In React applications, always fetch data server-side (e.g., Next.js Server Components, API routes, or server-side rendering).

Requirements

Node.js >= 20.0.0

Installation

# npm
npm install @localess/client

# yarn
yarn add @localess/client

# pnpm
pnpm add @localess/client

Getting Started

Initializing the Client

import { localessClient } from "@localess/client";

const client = localessClient({
  origin: 'https://my-localess.web.app', // Fully qualified domain with protocol
  spaceId: 'YOUR_SPACE_ID',              // Found in Localess Space settings
  token: 'YOUR_API_TOKEN',               // Found in Localess Space settings (keep secret!)
});

Client Options

Option	Type	Required	Default	Description
`origin`	`string`	✅	—	Fully qualified domain with protocol (e.g., `https://my-localess.web.app`)
`spaceId`	`string`	✅	—	Localess Space ID, found in Space settings
`token`	`string`	✅	—	Localess API token, found in Space settings
`version`	`'draft' \| string`	❌	`'published'`	Default content version to fetch
`debug`	`boolean`	❌	`false`	Enable debug logging
`cacheTTL`	`number \| false`	❌	`300000`	Cache TTL in milliseconds (5 minutes). Set `false` to disable caching

Fetching Content

`getContentBySlug<T>(slug, params?)`

Fetch a content document by its slug path. Supports generic typing for full type safety.

// Basic usage
const content = await client.getContentBySlug('docs/overview');

// With type safety (requires generated types from @localess/cli)
import type { Page } from './.localess/localess';

const content = await client.getContentBySlug<Page>('home', {
  locale: 'en',
  resolveReference: true,
  resolveLink: true,
});

`getContentById<T>(id, params?)`

Fetch a content document by its unique ID. Accepts the same parameters as getContentBySlug.

const content = await client.getContentById<Page>('FRnIT7CUABoRCdSVVGGs', {
  locale: 'de',
  version: 'draft',
});

Content Fetch Parameters

Parameter	Type	Default	Description
`version`	`'draft' \| string`	Client default	Override the client's default content version
`locale`	`string`	—	ISO 639-1 locale code (e.g., `'en'`, `'de'`)
`resolveReference`	`boolean`	`false`	Resolve content references inline
`resolveLink`	`boolean`	`false`	Resolve content links inline

Fetching Content Links

`getLinks(params?)`

Fetch all content links from the space, optionally filtered by type or parent.

// Fetch all links
const links = await client.getLinks();

// Fetch only documents under a specific parent
const legalLinks = await client.getLinks({
  kind: 'DOCUMENT',
  parentSlug: 'legal',
  excludeChildren: false,
});

Parameter	Type	Description
`kind`	`'DOCUMENT' \| 'FOLDER'`	Filter results by content kind
`parentSlug`	`string`	Filter by parent slug (e.g., `'legal/policy'`)
`excludeChildren`	`boolean`	When `true`, excludes nested sub-slugs from results

Fetching Translations

`getTranslations(locale)`

Fetch all translations for a given locale. Returns a flat key-value map.

const translations = await client.getTranslations('en');
// { "common.submit": "Submit", "nav.home": "Home", ... }

Assets

`assetLink(asset)`

Generate a fully qualified URL for a content asset.

import { localessClient } from "@localess/client";

const client = localessClient({ origin, spaceId, token });

// From a ContentAsset object
const url = client.assetLink(content.data.image);

// From a URI string
const url = client.assetLink('/spaces/abc/assets/photo.jpg');

Visual Editor Integration

`loadLocalessSync(origin, force?)`

Injects the Localess Visual Editor sync script into the document <head>. This enables live-editing capabilities when your site is opened inside the Localess Visual Editor.

import { loadLocalessSync } from "@localess/client";

loadLocalessSync('https://my-localess.web.app');

// Force injection even when not running inside an iframe
loadLocalessSync('https://my-localess.web.app', true);

`syncScriptUrl()`

Returns the URL of the Localess sync script, useful for manual script injection.

const scriptUrl = client.syncScriptUrl();

Marking Editable Content

Use these helpers to add Localess editable attributes to your HTML elements, enabling element selection and highlighting in the Visual Editor.

`localessEditable(content)`

Marks a content block as editable.

import { localessEditable } from "@localess/client";

// Returns: { 'data-ll-id': '...', 'data-ll-schema': '...' }
<section {...localessEditable(content.data)}>...</section>

`localessEditableField<T>(fieldName)`

Marks a specific field within a content block as editable, with type-safe field name inference.

import { localessEditableField } from "@localess/client";

// Returns: { 'data-ll-field': 'title' }
<h1 {...localessEditableField<MyPage>('title')}>...</h1>

Deprecated: llEditable() and llEditableField() are deprecated aliases. Use localessEditable() and localessEditableField() instead.

Listening to Visual Editor Events

When your application is loaded inside the Localess Visual Editor, you can subscribe to editing events via window.localess.

if (window.localess) {
  // Subscribe to a single event
  window.localess.on('change', (event) => {
    if (event.type === 'change') {
      setPageData(event.data);
    }
  });

  // Subscribe to multiple events
  window.localess.on(['input', 'change'], (event) => {
    if (event.type === 'input' || event.type === 'change') {
      setPageData(event.data);
    }
  });
}

Available Event Types

Event	Payload	Description
`input`	`{ type: 'input', data: any }`	Fired while a field is being edited (real-time)
`change`	`{ type: 'change', data: any }`	Fired after a field value is confirmed
`save`	`{ type: 'save' }`	Fired when content is saved
`publish`	`{ type: 'publish' }`	Fired when content is published
`pong`	`{ type: 'pong' }`	Heartbeat response from the editor
`enterSchema`	`{ type: 'enterSchema', id, schema, field? }`	Fired when hovering over a schema element
`hoverSchema`	`{ type: 'hoverSchema', id, schema, field? }`	Fired when entering a schema element

Caching

All API responses are cached by default using a TTL (time-to-live) cache. You can configure caching when initializing the client.

// Default: 5-minute TTL cache
const client = localessClient({ origin, spaceId, token });

// Custom TTL (e.g., 10 minutes)
const client = localessClient({ origin, spaceId, token, cacheTTL: 600000 });

// Disable caching entirely
const client = localessClient({ origin, spaceId, token, cacheTTL: false });

Type Reference

`Content<T>`

interface Content<T extends ContentData> extends ContentMetadata {
  data?: T;
  links?: Links;        // Populated when resolveLink: true
  references?: References; // Populated when resolveReference: true
}

`ContentMetadata`

interface ContentMetadata {
  id: string;
  name: string;
  kind: 'FOLDER' | 'DOCUMENT';
  slug: string;
  fullSlug: string;
  parentSlug: string;
  publishedAt?: string;
  createdAt: string;
  updatedAt: string;
}

`ContentData`

Base type for all content schema data objects.

interface ContentDataSchema {
  _id: string;
  _schema: string;
}

interface ContentData extends ContentDataSchema {
  [field: string]: ContentDataField | undefined;
}

`ContentAsset`

interface ContentAsset {
  kind: 'ASSET';
  uri: string;
}

`ContentLink`

interface ContentLink {
  kind: 'LINK';
  type: 'url' | 'content';
  target: '_blank' | '_self';
  uri: string;
}

`ContentReference`

interface ContentReference {
  kind: 'REFERENCE';
  uri: string;
}

`ContentRichText`

interface ContentRichText {
  type?: string;
  content?: ContentRichText[];
}

`Links`

A key-value map of content IDs to ContentMetadata objects.

`References`

A key-value map of reference IDs to Content objects.

`Translations`

A key-value map of translation keys to translated string values.

Utility Functions

Function	Returns	Description
`isBrowser()`	`boolean`	Returns `true` if code is running in a browser environment
`isServer()`	`boolean`	Returns `true` if code is running in a server/Node.js environment
`isIframe()`	`boolean`	Returns `true` if the page is rendered inside an iframe

AI Coding Agents

This package ships a SKILL.md file that provides AI coding agents (GitHub Copilot, Claude Code, Cursor, and others) with accurate, up-to-date APIs, patterns, and best practices. Most agents automatically read SKILL.md when starting a session.

Using SKILL.md in your project

SKILL.md is included in the npm package, so it is available locally after installation. Reference it from your project's AGENTS.md to ensure your agent reads accurate Localess documentation every session:

## Localess

@node_modules/@localess/client/SKILL.md

The @ prefix is the syntax used by most agent tools (GitHub Copilot, Claude Code, Cursor) to import file contents inline into the agent context.

When you change the public API of this package, update SKILL.md alongside your code:

New option or parameter → add it to the relevant options table and usage example
Changed behaviour → update the description and any affected code snippets
Deprecated API → mark it clearly and point to the replacement

License

MIT