> ## 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 ; 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or unversioned operation only when no newer versioned equivalent exists — the company-v0 notes below list the known superseded operations.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. # Property schemas and defaults > Create clear builder fields, theme-aware defaults, and resilient widget inputs. A widget property schema defines its builder editor. Put each prop's author-facing description on the field that produces that prop. ## Define useful fields Each prop-producing field needs: * a stable `key`; * a clear `label`; * a precise `description`; * a valid default when the field supports one. Section headers and separators organize the editor but do not produce props. Use [`WidgetSourcePropertyField`](/portal-widgets/reference/widget-worker-sdk/types/WidgetSourcePropertyField) and [`WidgetSourcePropertySchema`](/portal-widgets/reference/widget-worker-sdk/interfaces/WidgetSourcePropertySchema) for current field types and required members. ## Keep defaults valid The widget's `defaultProps` and field defaults must satisfy the same property contract. New widget instances should render a useful state without manual setup. Components must also handle missing, empty, partial, or malformed JSON without crashing. ## Use theme-aware visual fields Use `colorSelect` when an author must choose a color. It stores a semantic theme token. Do not add new uses of the deprecated `color` field. Prefer the host theme for typography, spacing, radii, borders, shadows, focus, and charts. Add a widget-owned visual field only when the product requirement cannot use a semantic theme value. See [Runtime, styling, and accessibility](/portal-widgets/widget-packages/runtime-and-accessibility#use-portal-theme-semantics) for the supported theme-variable families and a complete CSS example. ## Describe data-source results When a prop exists only as a data-source result, describe it on the canonical data-source field and keep its target-prop mapping synchronized. Prefer host data sources and props to direct network requests. ## Validate the editor contract Test a new widget instance, every field type, empty data, and invalid persisted values. Confirm that author labels and descriptions explain the outcome rather than the implementation.