> ## Documentation Index > Fetch the complete documentation index at: https://docs.arcuserp.com/llms.txt > Use this file to discover all available pages before exploring further. # Void a vendor bill > Voids a vendor bill, posting a reversing GL journal entry that undoes the original AP accrual; only a bill in `draft` or `approved` status with no recorded payments can be voided, and a voided bill cannot be reopened. Requires `purchasing:write` scope plus the per-user `accounting.approve_bill` permission. ## OpenAPI ````yaml /openapi.yaml delete /vendor-bills/{id} openapi: 3.1.0 info: title: Arcus ERP Public API version: 1.0.0 description: > Arcus ERP public REST API. Designed for external integrations and data migration. **Authentication.** Bearer token (API key) via the `Authorization` header. Format: `Authorization: Bearer ark_live_ent__` (or `ark_test_*` for sandbox). API keys are issued per-entity in **Settings > Developers > API Keys**. **Entity scoping.** The entity is encoded in the API key prefix; routes are flat (e.g. `/v1/accounts`, `/v1/orders`, `/v1/products`). A small set of platform endpoints (migration, reconciliation, events, webhook endpoints, API keys) use the `/v1/entities/{entity_id}/...` form -- those are noted in their tags. **Key capabilities.** - Related-resource hydration via `?expand[]=` (see `x-arcus-expand` on each resource). - Cursor-based pagination (`starting_after` / `ending_before` / `limit`). - Idempotency via the `Idempotency-Key` header. - Webhook events for asynchronous notification. - Conditional requests / ETag for cache validation. **Changelog.** Entries are dated and name every published contract whose MEANING moved, not only the ones whose field names changed. The narrative version of the same entries, written for integrators, is published at https://arcuserp.mintlify.app/changelog. **2026-09-22 (planned 2026-09-21), REORDER-BUYER-TRUTH: demand changed what it MEANS on three published contracts, with no field renamed.** An integrator that pins field names sees no breakage and different numbers, which is why this entry exists. - **Demand now counts build consumption.** `demand_avg_per_day` on the public product, kit and inventory-balance objects, and `daily_demand` / `demand_basis` / `net_suggested_qty` on `GET /v1/purchasing/reorder-report`, are composed from fulfilled sales lines PLUS posted `build_consume` inventory draws: each physical decrement of a product counts exactly once. The previous rule adopted an internal-consumption basis only when the sales blend was exactly zero, so a product both sold AND consumed into work orders planned as if the build draws did not exist. Products drawn into work orders move; on one production-shaped dataset five did, the largest from 0.05/day to 14.95/day. - **`demand_basis` now carries four values, not two:** `sales`, `sales_and_builds`, `builds` and `consumption`. A consumer with a two-branch reader (anything that is not `consumption` is `sales`) silently hides the two new ones. - **`current_demand_units` on `GET /v1/inventory/balances/:id` moved, by a second rule.** It counts committed-but-unshipped CUSTOMER demand, and it now counts a kit component's own line rather than its parent kit line, and excludes non-sales documents. On one production dataset 269 of 1,043 balance rows changed, 227 of them downward; the largest single move was 1,941 to 25, on a product whose open PURCHASE order line had been reported as customer demand. Re-baseline anything that alerts or reorders off this field. - `run_rate_30/90/180/365` and `blended_daily` on the same balance object move for the first reason above. - **Added, not changed:** `GET /v1/purchasing/reorder-report` accepts `demand_window` and returns the unit, cover-through and reorder-point-provenance fields documented on that operation; `order_multiple` is accepted and returned on the product-vendor doors. - **Volume note.** The `inventory.low_stock`, `inventory.out_of_stock` and `inventory.back_in_stock` webhook events are population-gated on `on_hand <= reorder_point`, and reorder points move with the demand above, so subscribers should expect a one-time step change in event volume around the release. servers: - url: https://api.arcuserp.com/v1 description: Arcus ERP API (accepts both live `ark_live_*` and test `ark_test_*` keys) - url: https://dev-api.arcuserp.com/v1 description: >- Dev sandbox API (test-only data, accepts `ark_test_*` keys against dev RDS) security: [] paths: /vendor-bills/{id}: parameters: - name: id in: path required: true schema: type: string format: uuid delete: tags: - Purchasing summary: Void a vendor bill description: >- Voids a vendor bill, posting a reversing GL journal entry that undoes the original AP accrual; only a bill in `draft` or `approved` status with no recorded payments can be voided, and a voided bill cannot be reopened. Requires `purchasing:write` scope plus the per-user `accounting.approve_bill` permission. operationId: voidVendorBillV1 responses: '200': description: Voided vendor bill content: application/json: schema: $ref: '#/components/schemas/VendorBill' '401': $ref: '#/components/responses/Error' '403': $ref: '#/components/responses/Error' '404': $ref: '#/components/responses/Error' security: - ApiKeyAuth: [] components: schemas: VendorBill: type: object description: A vendor invoice (AP). Posts to AP and inventory/expense on approval. properties: id: type: string format: uuid object: type: string enum: - vendor_bill entity_id: type: string format: uuid readOnly: true bill_number: type: string readOnly: true description: Sequential bill number per entity. vendor_invoice_number: type: string nullable: true description: Vendor's invoice number. vendor_id: type: string format: uuid po_id: type: string format: uuid nullable: true status: type: string enum: - draft - pending_approval - approved - rejected - paid - partially_paid - voided readOnly: true bill_date: type: string format: date description: The vendor's document date. effective_date: type: string format: date description: >- The posting date: the date the bill's journal entries post to the general ledger and the anchor of its due date. Defaults to bill_date. It may be ahead of or behind bill_date inside the entity's posting-date window (Settings > Fiscal Year); a posted bill's posting date moves only through a linked pair of correcting entries, never by editing this field. posted_entry_date: type: string format: date nullable: true readOnly: true description: >- The date of the bill's own journal entry (returned by GET /v1/vendor_bills/{id}). ledger_posting_date: type: string format: date nullable: true readOnly: true description: >- The date the bill's liability sits on in the ledger now, which follows a posting-date correction (returned by GET /v1/vendor_bills/{id}). redate_block: type: object nullable: true readOnly: true description: >- Null when the bill's posting date can still be moved; otherwise why not, as the re-date door would refuse it (for example `bill_terminal` for a voided bill). Returned by GET /v1/vendor_bills/{id}. properties: code: type: string message: type: string description: The sentence to show the operator. redate_latest_date: type: string format: date nullable: true readOnly: true description: >- The latest date the bill's posting date may move to: the first day money or credit relieved the bill (a posted payment, an applied vendor credit, an applied prepayment), so the vendor's payable never runs negative in between; null when nothing has relieved it. Returned by GET /v1/vendor_bills/{id}. posting_corrections: type: array readOnly: true description: >- Every posting-date correction of this bill, newest first. Each is a linked pair of CORRECTION journal entries: the OUT leg removes the liability from `from_date` and the IN leg records it on `to_date`. At most one pair is `live` (the one carrying the liability now). Returned by GET /v1/vendor_bills/{id}. items: type: object properties: sequence: type: integer out_entry_id: type: string format: uuid out_entry_number: type: string from_date: type: string format: date corrects_je_id: type: string format: uuid description: The entry the OUT leg corrects. in_entry_id: type: string format: uuid in_entry_number: type: string to_date: type: string format: date created_by: type: string format: uuid nullable: true created_by_name: type: string nullable: true created_at: type: string format: date-time live: type: boolean description: True for the one pair that carries the bill's liability now. reason: type: string nullable: true description: The operator's reason, from the correction's audit row. due_date: type: string format: date nullable: true subtotal: type: number tax_total: type: number shipping_total: type: number bill_total: type: number amount_paid: type: number readOnly: true balance_due: type: number readOnly: true description: >- bill_total minus amount_paid. Unlike the sales-side `orders.balance_due`, this is NEVER coerced to 0 by document lifecycle: a draft or terminal vendor bill still reports its true remaining payable. There is therefore no separate `amount_due` field on this resource. SSOT: utils/ap-helpers.mjs::updateAPBalance. currency: type: string default: USD payment_term_id: type: string format: uuid nullable: true notes: type: string nullable: true metadata: type: object nullable: true created_at: type: string format: date-time readOnly: true updated_at: type: string format: date-time readOnly: true landed_receipts_reached: type: array readOnly: true description: >- Every receipt the bill's landed allocations reached, in all three modes (Case A, a landed-only bill naming a PO, a receipt set); allocated_amount only for a caller with the margin permission (never an API key today). Returned by GET /v1/vendor-bills/{id}. items: type: object properties: kind: type: string enum: - receipt - drop_ship receiving_transaction_id: type: string format: uuid nullable: true purchase_receipt_id: type: string format: uuid nullable: true reference_number: type: string nullable: true po_id: type: string format: uuid nullable: true po_number: type: string nullable: true received_date: type: string format: date nullable: true allocation_rows: type: integer allocated_amount: type: number description: Omitted without the margin permission. ErrorEnvelope: type: object description: | Canonical error response envelope. All API errors use this shape. required: - error - code properties: error: type: string description: Machine-readable error key example: not_found code: type: string description: Machine-readable error code (often same as error) example: not_found type: type: string enum: - validation_error - permission_error - not_found - conflict - rate_limit - internal - expand_error - not_implemented example: not_found hint: type: string description: Human-readable one-sentence explanation (English) example: >- The requested order does not exist or does not belong to this entity. param: type: string description: The parameter that caused the error, if applicable example: expand[0] required: type: string description: The scope required (only on insufficient_scope errors) example: accounts:read request_id: type: string description: >- Unique request ID for support tracing (maps to CloudWatch log stream) example: req_abc123 responses: Error: description: Error response (400/401/403/404/409/422/429/500) content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' securitySchemes: ApiKeyAuth: type: http scheme: bearer description: | API key issued per entity via Settings > Developers > API Keys. Each key carries scopes (e.g. orders:read, products:write). Bearer token format: Authorization: Bearer ark_live_ent__ Test keys use ark_test_ent__. Both are issued per entity via Settings > Developers > API Keys. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.