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+# KROW Workforce API Contracts
+
+This document captures all API contracts used by the Staff and Client mobile applications. It serves as a single reference document to understand what each endpoint does, its expected inputs, returned outputs, and any non-obvious details.
+
+---
+
+## Staff Application
+
+### Authentication / Onboarding Pages (Get Started, Intro, Phone Verification, Profile Setup, Personal Info)
+#### Setup / User Validation API
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/getUserById` |
+| **Purpose** | Retrieves the base user profile to determine authentication status and role access (e.g., if user is STAFF). |
+| **Operation** | Query |
+| **Inputs** | `id: UUID!` (Firebase UID) |
+| **Outputs** | `User { id, email, phone, role }` |
+| **Notes** | Required after OTP verification to route users. |
+
+#### Create Default User API
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/createUser` |
+| **Purpose** | Inserts a base user record into the system during initial signup. |
+| **Operation** | Mutation |
+| **Inputs** | `id: UUID!`, `role: UserBaseRole` |
+| **Outputs** | `id` of newly created User |
+| **Notes** | Used explicitly during the "Sign Up" flow if the user doesn't exist. |
+
+#### Get Staff Profile API
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/getStaffByUserId` |
+| **Purpose** | Finds the specific Staff record associated with the base user ID. |
+| **Operation** | Query |
+| **Inputs** | `userId: UUID!` |
+| **Outputs** | `Staffs { id, userId, fullName, email, phone, photoUrl, status }` |
+| **Notes** | Needed to verify if a complete staff profile exists before fully authenticating. |
+
+#### Update Staff Profile API
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/updateStaff` |
+| **Purpose** | Saves onboarding data across Personal Info, Experience, and Preferred Locations pages. |
+| **Operation** | Mutation |
+| **Inputs** | `id: UUID!`, `fullName`, `email`, `phone`, `addres`, etc. |
+| **Outputs** | `id` |
+| **Notes** | Called incrementally during profile setup wizard. |
+
+### Home Page (worker_home_page.dart) & Benefits Overview
+#### Load Today/Tomorrow Shifts
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/getApplicationsByStaffId` |
+| **Purpose** | Retrieves applications (shifts) assigned to the current staff member within a specific date range. |
+| **Operation** | Query |
+| **Inputs** | `staffId: UUID!`, `dayStart: Timestamp`, `dayEnd: Timestamp` |
+| **Outputs** | `Applications { shift, shiftRole, status, createdAt }` |
+| **Notes** | The frontend filters the query response for `CONFIRMED` applications to display "Today's" and "Tomorrow's" shifts. |
+
+#### List Recommended Shifts
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/listShifts` |
+| **Purpose** | Fetches open shifts that are available for the staff to apply to. |
+| **Operation** | Query |
+| **Inputs** | None directly mapped, but filters OPEN shifts purely on the client side at the time. |
+| **Outputs** | `Shifts { id, title, orderId, cost, location, startTime, endTime, status }` |
+| **Notes** | Limits output to 10 on the frontend. Should ideally rely on a `$status: OPEN` parameter. |
+
+#### Benefits Summary API
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/listBenefitsDataByStaffId` |
+| **Purpose** | Retrieves accrued benefits (e.g., Sick time, Vacation) to display on the home screen. |
+| **Operation** | Query |
+| **Inputs** | `staffId: UUID!` |
+| **Outputs** | `BenefitsDatas { vendorBenefitPlan { title, total }, current }` |
+| **Notes** | Calculates `usedHours = total - current`. |
+
+### Find Shifts / Shift Details Pages (shifts_page.dart)
+#### List Available Shifts Filtered
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/filterShifts` |
+| **Purpose** | Used to fetch Open Shifts in specific regions when the worker searches in the "Find Shifts" tab. |
+| **Operation** | Query |
+| **Inputs** | `$status: ShiftStatus`, `$dateFrom: Timestamp`, `$dateTo: Timestamp` |
+| **Outputs** | `Shifts { id, title, location, cost, durationDays, order { business, vendor } }` |
+| **Notes** | - |
+
+#### Get Shift Details
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/getShiftById` |
+| **Purpose** | Gets deeper details for a single shift including exact uniform/managers needed. |
+| **Operation** | Query |
+| **Inputs** | `id: UUID!` |
+| **Outputs** | `Shift { id, title, hours, cost, locationAddress, workersNeeded ... }` |
+| **Notes** | - |
+
+#### Apply To Shift
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/createApplication` |
+| **Purpose** | Worker submits an intent to take an open shift. |
+| **Operation** | Mutation |
+| **Inputs** | `shiftId`, `staffId`, `status: APPLIED` |
+| **Outputs** | `Application ID` |
+| **Notes** | A shift status will switch to `CONFIRMED` via admin approval. |
+
+### Availability Page (availability_page.dart)
+#### Get Default Availability
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/listStaffAvailabilitiesByStaffId` |
+| **Purpose** | Fetches the standard Mon-Sun recurring availability for a staff member. |
+| **Operation** | Query |
+| **Inputs** | `staffId: UUID!` |
+| **Outputs** | `StaffAvailabilities { dayOfWeek, isAvailable, startTime, endTime }` |
+| **Notes** | - |
+
+#### Update Availability
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/updateStaffAvailability` (or `createStaffAvailability`) |
+| **Purpose** | Upserts availability preferences. |
+| **Operation** | Mutation |
+| **Inputs** | `staffId`, `dayOfWeek`, `isAvailable`, `startTime`, `endTime` |
+| **Outputs** | `id` |
+| **Notes** | Called individually per day edited. |
+
+### Payments Page (payments_page.dart)
+#### Get Recent Payments
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/listRecentPaymentsByStaffId` |
+| **Purpose** | Loads the history of earnings and timesheets completed by the staff. |
+| **Operation** | Query |
+| **Inputs** | `staffId: UUID!` |
+| **Outputs** | `Payments { amount, processDate, shiftId, status }` |
+| **Notes** | Displays historical metrics under Earnings tab. |
+
+### Compliance / Profiles (Agreements, W4, I9, Documents)
+#### Get Tax Forms
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/getTaxFormsByStaffId` |
+| **Purpose** | Check the filing status of I9 and W4 forms. |
+| **Operation** | Query |
+| **Inputs** | `staffId: UUID!` |
+| **Outputs** | `TaxForms { formType, isCompleted, updatedDate }` |
+| **Notes** | Required for staff to be eligible for shifts. |
+
+#### Update Tax Forms
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/updateTaxForm` |
+| **Purpose** | Submits state and filing for the given tax form type. |
+| **Operation** | Mutation |
+| **Inputs** | `id`, `dataPoints...` |
+| **Outputs** | `id` |
+| **Notes** | Updates compliance state. |
+
+---
+
+## Client Application
+
+### Authentication / Intro (Sign In, Get Started)
+#### Client User Validation API
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/getUserById` |
+| **Purpose** | Retrieves the base user profile to determine authentication status and role access (e.g., if user is BUSINESS). |
+| **Operation** | Query |
+| **Inputs** | `id: UUID!` (Firebase UID) |
+| **Outputs** | `User { id, email, phone, userRole }` |
+| **Notes** | Must check if `userRole == BUSINESS` or `BOTH`. |
+
+#### Get Business Profile API
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/getBusinessByUserId` |
+| **Purpose** | Maps the authenticated user to their client business context. |
+| **Operation** | Query |
+| **Inputs** | `userId: UUID!` |
+| **Outputs** | `Business { id, businessName, email, contactName }` |
+| **Notes** | Used to set the working scopes (Business ID) across the entire app. |
+
+### Hubs Page (client_hubs_page.dart, edit_hub.dart)
+#### List Hubs
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/listTeamHubsByBusinessId` |
+| **Purpose** | Fetches the primary working sites (Hubs) for a client. |
+| **Operation** | Query |
+| **Inputs** | `businessId: UUID!` |
+| **Outputs** | `TeamHubs { id, hubName, address, contact, active }` |
+| **Notes** | - |
+
+#### Update / Delete Hub
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/updateTeamHub` / `/deleteTeamHub` |
+| **Purpose** | Edits or archives a Hub location. |
+| **Operation** | Mutation |
+| **Inputs** | `id: UUID!`, `hubName`, `address`, etc (for Update) |
+| **Outputs** | `id` |
+| **Notes** | - |
+
+### Orders Page (create_order, view_orders)
+#### Create Order
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/createOrder` |
+| **Purpose** | The client submits a new request for temporary staff (can result in multiple Shifts generated on the backend). |
+| **Operation** | Mutation |
+| **Inputs** | `businessId`, `eventName`, `orderType`, `status` |
+| **Outputs** | `id` (Order ID) |
+| **Notes** | This creates an order. Shift instances are subsequently created through secondary mutations. |
+
+#### List Orders
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/getOrdersByBusinessId` |
+| **Purpose** | Retrieves all ongoing and past staff requests from the client. |
+| **Operation** | Query |
+| **Inputs** | `businessId: UUID!` |
+| **Outputs** | `Orders { id, eventName, shiftCount, status }` |
+| **Notes** | - |
+
+### Billing Pages (billing_page.dart, pending_invoices)
+#### List Invoices
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/listInvoicesByBusinessId` |
+| **Purpose** | Fetches "Pending", "Paid", and "Disputed" invoices for the client to review. |
+| **Operation** | Query |
+| **Inputs** | `businessId: UUID!` |
+| **Outputs** | `Invoices { id, amountDue, issueDate, status }` |
+| **Notes** | Used across all Billing view tabs. |
+
+#### Mark Invoice
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/updateInvoice` |
+| **Purpose** | Marks an invoice as disputed or pays it (changes status). |
+| **Operation** | Mutation |
+| **Inputs** | `id: UUID!`, `status: InvoiceStatus` |
+| **Outputs** | `id` |
+| **Notes** | Disputing usually involves setting a memo or flag. |
+
+### Reports Page (reports_page.dart)
+#### Get Coverage Stats
+| Field | Description |
+|---|---|
+| **Endpoint name** | `/getCoverageStatsByBusiness` |
+| **Purpose** | Provides data on fulfillments rates vs actual requests. |
+| **Operation** | Query |
+| **Inputs** | `businessId: UUID!` |
+| **Outputs** | `Stats { totalRequested, totalFilled, percentage }` |
+| **Notes** | Driven mostly by aggregated backend views. |
+
+---
+
+*This document reflects the current state of Data Connect definitions implemented across the frontend and mapped manually by reviewing Repository and UI logic.*