> ## 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. > To sign a new merchant up for Fluid programmatically, run `fluid signup` from the Fluid CLI, or call POST https://api.fluid.app/api/company with no credentials, as described in /api/agent-signup. Do not automate the signup form or book a demo. Before authenticated calls are possible, the merchant must sign the agent in to the Fluid CLI with the emailed code and --shop set to the company's fluid_shop (which also confirms the signup), or open the emailed confirmation link and give the agent an API token. > After signup, to launch a merchant's store (back-office sync, payments onboarding, store setup, a theme copied from their current site, and a preview link before billing), follow /api/agent-launch. > 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or unversioned operation only when no newer versioned equivalent exists — the company-v0 notes below list the known superseded operations. The same applies to /api/company/v1 and /api/v1/... paths: prefer a newer documented equivalent, and use one only when none exists (/api/v1.1/... is distinct and documented in company-v0). Use page/per_page offset pagination only on an operation whose spec documents those params — mostly the unversioned company-v0 admin surface, plus some lists on other surfaces, versioned ones included; page every other list with cursors. > Fluid has three navigation APIs; don't mix them up. Storefront website menus (navigation bars, footers) are /api/menus and nested menu_items, in api-reference/content-v0.yaml (API Reference: Website > Navigation menus), with a how-to in themes/navigation-menus; their list uses flat page/per_page pagination. The Fluid mobile app's navigation is /api/v2/mobile_navigations, in api-reference/mobile-v2.yaml (API Reference: Mobile app > Navigation); its list also uses page/per_page. Portal navigations belong to a portal definition (Fluid OS), in api-reference/fluid-os-v0.yaml (API Reference: Portal > Portal navigation), and each has a platform of web or mobile. > 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/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 except two operations that take no credential, POST /api/company (create a company) and GET /api/agreements/{id} — 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/members-v2025-06.yaml covers the v2025-06 unified Member identity surface (/api/v2025-06/members/... paths, bearer-authenticated — member list/create/show/update, lookup by email/username/external_id/legacy_customer_id, member-type assignment, and the sponsor genealogy read). Prefer it over the customers and reps surfaces when the member type matters: /customers does not serialize member_type. 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. > The Help Center (/help/...) is for merchants, admins and reps using Fluid. Its admin pages mirror the admin's routes: the screen at admin.fluid.app/settings/taxes is documented at /help/admin/settings/taxes. Use the Help Center for how-to questions about the admin, and the Developer Platform and API Reference for building integrations. > Help Center pages describe what a company admin sees. A reader's role can hide screens and actions; admins manage roles on Settings > Roles (/help/admin/settings/roles). If someone can't find a screen or button, their role's permissions are the first thing to check. > Send people who need Fluid support to /help/getting-help. Don't invent support email addresses, phone numbers or response times. # Update customer address (PUT) > The PUT form of `PATCH /api/checkout/v2026-04/customers/me/addresses/{id}`. Both methods reach one update action, take the same body and return the same responses. Read that operation for the details. ## OpenAPI ````yaml /api-reference/checkout-v2026-04.yaml put /api/checkout/v2026-04/customers/me/addresses/{id} openapi: 3.1.0 info: title: Fluid Checkout API description: > **Fluid Checkout API — for building a checkout directly against REST.** Use this surface if you are integrating server-to-server or building your own checkout UI. It covers the full order lifecycle (cart → address → shipping → discount → complete → order) plus the logged-in customer's account: saved addresses, saved payment methods, order history, loyalty points, and subscription management (pause, resume, skip, cancel, retry). **The cart token in the URL scopes cart access** — creating a cart, adding items, applying a discount, and completing a cart need no bearer token. Among the cart operations, a Bearer token is required for `carts/{cart_token}/sync`, `carts/{cart_token}/volume_rep`, and `carts/{cart_token}/discount/manual`. It is also required conditionally when `PATCH carts/{cart_token}` selects an enrollment target with `member_type_id`; profile-only PATCH requests remain public. Off the cart, a token is required for everything under `customers/me` and `subscriptions`, and for the store and directory lookups (`store/config`, `store/languages`, `reps`, `users`), `subscription_bundles` and `subscription-profiles`. `store/countries` accepts a token but does not require one — it returns the same list either way. **If you are using the `@fluid-app` FairShare SDK in a theme or storefront, you are not calling this surface** — the SDK calls the Fluid Public SDK API (`public-v2025-06`). Do not mix the two against one cart: they share the same cart records and services, but their request shapes differ. See [Choosing a cart surface](https://docs.fluid.app/api/choosing-a-cart-surface) for the operation map and boundary. **Sandbox test companies.** A sandbox test company is linked to a live company. While the test company cannot be reached, because sandbox access is turned off for its live company or the live company was deleted: - a cart token for one of its carts answers exactly as a token no cart holds, with the operation's documented `404` (cart not found), so the response does not reveal that the cart exists; - an operation that resolves the company from a bearer credential refuses that credential with `403` and the body `{"error": ""}`, before the operation runs. These refusals are documented here once rather than on each operation. version: v2026-04 contact: email: support@fluid.app license: name: Proprietary identifier: LicenseRef-Proprietary servers: - url: https://api.fluid.app security: [] tags: - name: carts description: >- Create, read, and mutate checkout carts (email, address, country, language, shipping, recalculation, completion). - name: cart-auth description: >- Cart-scoped customer authentication — magic-link challenge, verification, identity, checkout handoff, and logout. x-fluid-section: Checkout - name: cart-discount description: >- Apply, list, and remove promo codes (discount codes) on a cart, including admin manual discounts. - name: cart-items description: Add, update, and remove line items on a cart. x-fluid-section: Checkout - name: cart-sms-consent description: >- The disclosure for recurring subscription texts and the shopper's choice about them on a cart. x-fluid-section: Checkout - name: cart-points description: Apply and remove loyalty points on a cart. - name: customers description: The authenticated customer's profile and company memberships. - name: customer-addresses description: The authenticated customer's saved shipping/billing addresses. - name: customer-orders description: The authenticated customer's order history. - name: customer-payment-methods description: The authenticated customer's saved payment methods and tokenization. - name: customer-points description: The authenticated customer's loyalty point balances. - name: directory description: Company rep and user directory lookups. - name: enrollments description: >- Public enrollment forms — retrieve a form and submit, update, or upload field answers. - name: orders description: Public order lookup by token. - name: products description: Public product queries for the storefront checkout. - name: store description: >- Store-level checkout configuration — countries, languages, address fields, agreements, drop zones, and Apple Pay domain verification. x-fluid-section: Checkout - name: subscriptions description: >- Manage subscriptions — pause, resume, skip, cancel, reactivate, retry, and failed-cycle waivers. x-fluid-section: Checkout - name: subscription-manage-link description: >- The subscriptions a manage link reaches. The bearer is the link's scoped token (`sml_...`, from the `manage_url` of the subscription_upcoming_renewal webhook), not a session. It names one company, the subscriptions of one renewal order and the actions it allows, and it expires at the end of the day after the local bill date. Only these operations accept it, and they accept no other credential. The responses carry no customer data. x-fluid-section: Checkout - name: subscription-sms-consent description: >- The recurring subscription texts choice for a customer's subscription, and the disclosure shown next to it. x-fluid-section: Checkout - name: subscription-bundles description: List and create subscription bundles. - name: subscription-profiles description: Change an autoship profile as a whole. Requires Subscription Pro. x-fluid-section: Checkout paths: /api/checkout/v2026-04/customers/me/addresses/{id}: put: tags: - customer-addresses summary: Update customer address (PUT) description: >- The PUT form of `PATCH /api/checkout/v2026-04/customers/me/addresses/{id}`. Both methods reach one update action, take the same body and return the same responses. Read that operation for the details. operationId: checkout_v2026_04_update_customer_address_put parameters: - name: id in: path required: true description: Address ID schema: type: integer requestBody: $ref: '#/components/requestBodies/UpdateCustomerAddress' responses: '200': $ref: '#/components/responses/UpdateCustomerAddressOk' '401': $ref: '#/components/responses/Unauthorized' '404': $ref: '#/components/responses/NotFound' '422': $ref: '#/components/responses/UnprocessableEntity' security: - bearer_auth: [] components: requestBodies: UpdateCustomerAddress: content: application/json: schema: type: object additionalProperties: false required: - address_id - address properties: address_id: type: integer description: >- Address ID. Read from the request body by UpdateAddressAction#params_schema, not the {id} path parameter. address: type: object additionalProperties: false properties: name: type: string address1: type: string address2: type: string city: type: string state: type: string postal_code: type: string country_id: type: integer country_code: type: string phone: type: - string - 'null' default: type: boolean example: address_id: 60427 address: address1: 310 Amherst Street postal_code: '03063' responses: UpdateCustomerAddressOk: description: Success content: application/json: schema: $ref: '#/components/schemas/CheckoutCustomerAddressResponse' example: address: id: 60427 name: Holly Flax address1: 310 Amherst Street address2: null address3: null city: Nashua state: NH subdivision_code: US-NH postal_code: '03063' country_code: US phone: '+16035550188' country_num_code: 840 default: false fluid_pay_account: id: 190334 meta: request_id: 1a8e5c2f-7d4b-4b9e-a6f3-3e0d8b2c5a94 timestamp: '2026-09-14T15:39:26Z' Unauthorized: description: Unauthorized content: application/json: schema: $ref: '#/components/schemas/UnauthorizedResponse' NotFound: description: Not Found content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' UnprocessableEntity: description: Unprocessable Entity content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' schemas: CheckoutCustomerAddressResponse: type: object properties: address: $ref: '#/components/schemas/CheckoutCustomerAddress' fluid_pay_account: oneOf: - $ref: '#/components/schemas/CheckoutFluidPayAccount' - type: 'null' meta: $ref: '#/components/schemas/Meta' required: - address - fluid_pay_account - meta additionalProperties: false UnauthorizedResponse: type: object properties: message: type: string required: - message ErrorResponse: type: object additionalProperties: false required: - error_message - errors - meta properties: error_message: type: string errors: $ref: '#/components/schemas/ErrorBag' meta: $ref: '#/components/schemas/CheckoutMeta' CheckoutCustomerAddress: $ref: '#/components/schemas/CheckoutCustomerProfileAddress' description: >- Saved customer address on the address-book endpoints (create/list/update via Commerce::Api::FluidPay::*AddressAction). Distinct from CheckoutAddress (never the wallet-partial `null`-only shape); same blueprinter and view as the profile address, so it aliases that schema. CheckoutFluidPayAccount: type: object properties: id: type: integer required: - id additionalProperties: false Meta: type: object required: - request_id - timestamp properties: request_id: type: - string - 'null' timestamp: type: string format: date-time ErrorBag: description: >- Validation errors keyed by field, a list of errors, a single error message, or null when no structured error details are available. anyOf: - type: string - type: array items: $ref: '#/components/schemas/ErrorValue' - type: object additionalProperties: $ref: '#/components/schemas/ErrorValue' - type: 'null' CheckoutMeta: type: object additionalProperties: false required: - request_id - timestamp properties: request_id: type: - string - 'null' timestamp: type: string format: date-time code: type: string description: >- Machine code for the refusal, for example `payment_unconfirmed`, or `next_bill_date_blackout` when a merchant caller (an admin credential) picks a bill date on a blackout day. A shopper is never refused for a blackout day. Their date is saved on the next open day and the success response carries the saved date. blocked_date: type: string format: date description: >- Present with `next_bill_date_blackout`. The date that was refused, as an ISO 8601 calendar date. example: '2026-11-30' blocked_day: type: integer minimum: 1 maximum: 31 description: >- Present with `next_bill_date_blackout`. The day of the month of `blocked_date`. example: 30 allowed_date: type: string format: date description: >- Present with `next_bill_date_blackout`. The nearest date the merchant's blackout rules allow, the date to offer instead. example: '2026-11-28' payment_uuid: type: string description: >- Present with `payment_unconfirmed`. The payment to look up before charging again. error_details: type: array minItems: 1 description: >- Every reason this checkout was refused, each with a stable `code`, the cart `field` to fix, and the `payment` outcome. items: $ref: '#/components/schemas/CheckoutErrorDetail' coded_recovery: type: boolean description: >- Present and true when the company routes checkout refusals by `error_details` (CHECKOUT_CODED_REFUSALS). Temporary; removed with that flag. CheckoutCustomerProfileAddress: description: >- Persisted address rendered by AddressBlueprinter (default view): the 13 fields are ungated so every key is always emitted (`id` non-null on a persisted row; the other column values are nullable strings). Used by the customer profile payload and, via the CheckoutCustomerAddress alias, by the customer address-book endpoints. type: object additionalProperties: false required: - id - name - address1 - address2 - address3 - city - state - subdivision_code - postal_code - country_code - phone - country_num_code - default properties: id: type: integer name: type: - string - 'null' address1: type: - string - 'null' address2: type: - string - 'null' address3: type: - string - 'null' city: type: - string - 'null' state: type: - string - 'null' subdivision_code: type: - string - 'null' postal_code: type: - string - 'null' country_code: type: - string - 'null' phone: type: - string - 'null' country_num_code: type: - integer - 'null' description: >- Numeric ISO country code resolved from the address country; null when the country cannot be resolved. default: type: - boolean - 'null' ErrorValue: description: A validation or API error value. anyOf: - type: string - type: array items: type: string - type: object additionalProperties: $ref: '#/components/schemas/JsonValue' CheckoutErrorDetail: description: >- One refusal reason, in the same vocabulary as `checkout_blockers`, with where to send the shopper and what happened to the payment. type: object additionalProperties: false required: - code - field - payment - message properties: code: type: string description: Stable refusal code. Codes reuse the `checkout_blockers` codes. field: type: - string - 'null' description: >- The cart API path to send the shopper to, for example `shipping_address.postal_code` or `items[123]`, or null. payment: type: string enum: - not_attempted - declined - unknown - held description: >- `not_attempted`: fix the cause and resubmit. `declined`: the payment was refused; resubmit with another method. `declined` reflects the stored payment status; for some gateways an unconfirmed failure is still reported as `declined`. `unknown`: money may have moved; check the order before charging again. `held`: the cart's only money is the payment a resubmit reuses. Fix the field and resubmit with the same payment method; checkout will not charge again. message: type: string description: The English message for this entry. Not translated. JsonValue: description: >- Any valid JSON value for provider, integration, theme, metadata, or other dynamic payloads whose keys are not fixed by the API contract. anyOf: - type: string - type: number - type: boolean - type: 'null' - type: array items: $ref: '#/components/schemas/JsonValue' - type: object additionalProperties: $ref: '#/components/schemas/JsonValue' securitySchemes: bearer_auth: type: http scheme: bearer description: Bearer token authentication ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.