> ## Documentation Index
> Fetch the complete documentation index at: https://docs.fluid.app/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> For new direct REST integrations, use the v2026-04 surfaces. The @fluid-app FairShare SDK continues to use its own published public-v2025-06 contract.
> Authenticate with the header Authorization: Bearer <token>; public storefront read endpoints require no auth.
> Lists use cursor pagination via the page[cursor] and page[limit] query params; follow meta.pagination.next_cursor until it is null.
> When the same operation exists on more than one surface, use the newest: dated API versions are newer than unversioned ones, and later dates win (v2026-04 > v2025-06 > unversioned v0/v1.1). Fall back to a legacy or unversioned operation only when no newer versioned equivalent exists — the company-v0 notes below list the known superseded operations. /api/company/v1 and /api/v1/... paths are documented in no spec here and must never be used (/api/v1.1/... is distinct and documented in company-v0). Use page/per_page offset pagination only where a spec documents it — in practice the unversioned company-v0 admin surface; every versioned surface uses cursor pagination.
> The OpenAPI specs under api-reference/ are the authoritative contracts; prefer them over prose when in doubt. api-reference/storefront-v2026-04.yaml covers the v2026-04 storefront surface (/api/v202604/... paths); api-reference/auth-v0.yaml covers the unversioned auth surface (/api/... paths — authentication, MFA, social auth, and token exchange); api-reference/checkout-v2026-04.yaml covers the v2026-04 checkout surface (/api/checkout/v2026-04/... paths — carts, cart auth, discounts, items, subscriptions, orders, enrollments, and store config); api-reference/public-v2025-06.yaml covers the Public SDK surface used by the @fluid-app FairShare SDK, including its parallel cart lifecycle, browser integrations, versioned payment callbacks, unversioned public utilities, and the cart price-override operation; api-reference/payment-v2026-04.yaml covers the v2026-04 payment gateway admin surface (/api/payment/v2026-04/... paths, bearer-authenticated — gateway CRUD, gateway purchase/authorize/$0-verify, transaction list/show and capture/void/credit, and merchant payment configuration); api-reference/payments-v2026-04.yaml covers the v2026-04 cart payment surface (/api/payments/v2026-04/carts/{cart_token}/... paths, authenticated by the cart token in the path with no bearer — payment-method selection, VGS card tokenization, 3D Secure verification, and PayPal/Braintree/Klarna/Apple Pay flows); api-reference/commerce-v2026-04.yaml covers the v2026-04 commerce order-editing surface (/api/v202604/orders/{order_id}/edits paths, bearer-authenticated — post-checkout order edits that atomically insert items and add adjustments/discounts, with an optional dry-run preview); api-reference/webhooks-v0.yaml covers the unversioned webhooks surface (/api/... paths — webhook registration, delivery payloads, callback registrations, company events, and webhook/callback schemas); api-reference/company-v0.yaml covers the legacy unversioned company admin surface (/api/... paths, bearer-authenticated — company settings and management, customers, users, roles, subscription plans, subscription bundles, subscriptions, media, pages, catch-ups, inventory levels, domains, agreements, and admin order actions). company-v0 caveats: it is the legacy v0 admin contract and its lists use flat page/per_page offset pagination, which is expected there despite the general cursor-pagination rule; where an operation exists in both company-v0 and a versioned spec, prefer the versioned spec — the subscriptions lifecycle (list/create/show/update, cancel, pause, reactivate, resume, retry, skip, failed-cycle-waiver, discounts) and subscription bundles are superseded by checkout-v2026-04, and company pages/media CRUD plus the public pages, categories, products, and media list endpoints are superseded by storefront-v2026-04. Subscription plan management (/api/subscription_plans, resource-wrapped {"subscription_plan": {...}} bodies) exists only in company-v0. api-reference/analytics-v2026-04.yaml covers the v2026-04 Home dashboard analytics surface (/api/v202604/analytics/dashboard/... paths, bearer-authenticated — read-only endpoints for the Home > Overview, Home > Live, and Home > Field tabs, each accepting an optional country ISO alpha-2 query param that scopes aggregations to a single country).
> api-reference/analytics-v0.yaml covers the unversioned analytics surface that backs the fluid-admin Traffic tab (/api/analytics/... and /api/analytics/traffic/... paths, bearer-authenticated — the legacy shares/views/visitors summary plus traffic overview, ranked campaigns, sources, geographies, flows, and per-rep breakdown, all sharing one reporting-period contract).
> Successful responses wrap the resource payload alongside a top-level integer status and a meta object.
> Portal Definition authoring edits and synchronizes the portal JSON resource graph. Widget Package authoring builds either a company-owned or Droplet-owned Remote DOM package. These are separate contracts; do not imply that one defines the other.
> For Widget Package worker code, use only @fluid-app/portal-sdk/widgets/worker. Use only the Portal Definition and Widget Package workflows and public entry points documented here; do not infer support for undocumented surfaces.
> Every portal function and declarative capability used by a widget must appear in that widget's uses array. Use the same typed function value in uses; do not invent capability-name strings.
> Widget styling must use the portal's semantic theme variables for colors, typography, spacing, radii, borders, focus, and charts whenever a token represents the visual decision. Do not create a separate light or dark palette or duplicate theme controls as widget properties.
> Prefer worker-safe Fluid UI components exported by @fluid-app/portal-sdk/widgets/worker when they fit the interaction. When no exported component fits, use semantic HTML, accessible behavior, and the portal theme variables.
> A Portal Definition push updates the remote working definition. A portal version is an immutable snapshot, and activation is a separate live release operation.

# Portal and widget development

> Build Portal Definitions and Remote DOM Widget Packages with Fluid's supported tools.

Fluid supports two separate development journeys:

* **Portal Definition authoring** edits the JSON resource graph that controls screens, navigation, profiles, themes, and built-in widget placement.
* **Widget Package authoring** builds reusable Remote DOM widgets that run inside a portal host.

These journeys use different contracts. A Portal Definition does not define a Widget Package, and a Widget Package does not replace portal JSON.

<CardGroup cols={2}>
  <Card title="Author a Portal Definition" icon="diagram-project" href="/portal-widgets/portal-definitions/quickstart">
    Pull a working definition, edit local JSON, preview it, push the draft, and activate an immutable version.
  </Card>

  <Card title="Build a Widget Package" icon="puzzle-piece" href="/portal-widgets/widget-packages/choose-package-model">
    Choose a company or Droplet package, define widgets, validate them, and publish runtime artifacts.
  </Card>
</CardGroup>

## Supported surfaces

Use these documentation contracts:

* The [Portal Definition Reference](/portal-widgets/reference/portal-definition) for portal resource types and built-in widget nodes.
* The [Widget Worker SDK Reference](/portal-widgets/reference/widget-worker) for `@fluid-app/portal-sdk/widgets/worker`.
* The generated Fluid CLI help for the commands installed in your project.

Use only the workflows and public entry points documented in this section.

## Choose your starting point

Use the Portal Definition quickstart when you need to change an existing portal's content or structure. Use the Widget Package guide when you need new reusable behavior that the built-in widgets do not provide.

<Note>
  You need Fluid credentials for remote pull, push, link, and publish operations. Local editing, type checking, and most build checks do not change remote state.
</Note>
