> ## 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. # Create a quick check > Creates and immediately prints a one-off check outside of a batch, for an urgent or ad-hoc vendor payment, given the payee, amount, and GL expense account to debit. Requires `purchasing:write` scope, and the journal entry posts immediately using the next number in the entity's check sequence. ## OpenAPI ````yaml /openapi.yaml post /quick-check 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: /quick-check: post: tags: - Purchasing summary: Create a quick check description: >- Creates and immediately prints a one-off check outside of a batch, for an urgent or ad-hoc vendor payment, given the payee, amount, and GL expense account to debit. Requires `purchasing:write` scope, and the journal entry posts immediately using the next number in the entity's check sequence. operationId: quickCheckV1 requestBody: required: true content: application/json: schema: type: object required: - vendor_id - amount - gl_account_id properties: vendor_id: type: string format: uuid amount: type: number gl_account_id: type: string format: uuid memo: type: string payment_date: type: string format: date responses: '201': description: Created quick check content: application/json: schema: $ref: '#/components/schemas/PrintedCheck' '400': $ref: '#/components/responses/Error' '401': $ref: '#/components/responses/Error' '403': $ref: '#/components/responses/Error' security: - ApiKeyAuth: [] components: schemas: PrintedCheck: type: object description: A check printed by Arcus (paper AP payment). properties: id: type: string format: uuid object: type: string enum: - printed_check entity_id: type: string format: uuid readOnly: true check_number: type: integer readOnly: true description: Sequential per bank account. bank_account_id: type: string format: uuid vendor_id: type: string format: uuid amount: type: number memo: type: string nullable: true status: type: string enum: - printed - reprinted - voided - cleared readOnly: true printed_at: type: string format: date-time readOnly: true voided_at: type: string format: date-time nullable: true readOnly: true cleared_at: type: string format: date-time nullable: true readOnly: true cleared_source: type: string nullable: true readOnly: true enum: - bank_match - manual_clear - register_only - migrated description: > The EVIDENCE CLASS behind status=cleared. `register_only` means the payment leg already credited a bank account and no journal entry was posted for the clear, so the row is a register truth and NOT a bank fact. Null on a check cleared before migration 20260915a, when nothing recorded the class. cleared_bank_transaction_id: type: string format: uuid nullable: true readOnly: true description: > The bank line that paid this check. Written when the clear is driven by a matched bank row; null for a manual clear and for every check cleared before 2026-09-18. When it is null the pairing may still be recorded on the bank side. cleared_bank_txn_id: type: string format: uuid nullable: true readOnly: true description: > RETRIEVE ONLY (GET /v1/printed-checks/{id}); absent from the list response. The RESOLVED bank line: `cleared_bank_transaction_id` when this check carries the forward stamp, otherwise the bank row whose `matched_printed_check_id` names this check. A check that is still `printed` has no forward stamp by definition, so this is the only field that can answer "which line will pay it" before the clear. Pass it as `bank_transaction_id` on POST /v1/printed-checks/{id}/clear and the relief is dated the day the BANK paid rather than today. drawn_on_bank_name: type: string nullable: true readOnly: true description: > RETRIEVE ONLY (GET /v1/printed-checks/{id}). The LIST response, GET /v1/printed-checks, does NOT carry it and carries no live-drawee field under any name: that door answers from the stored row, so the only bank name on a list item is the issue-time snapshot `bank_account_name`, and a list item can therefore name a bank this check is no longer drawn on. Retrieve the check to get this field. The name of the bank this check is CURRENTLY drawn on, resolved from `printed_checks.bank_account_id` (falling back to the linked AP payment's bank) and falling back to the issue-time snapshot `bank_account_name` only when no drawee resolves. It is a different fact from `bank_account_name`, which is what the PAPER said at issue time and is what a re-print reproduces: after the drawee is moved with PATCH /v1/printed-checks/{id}/bank the two disagree, and this field is the one that names the bank whose statement the check belongs on and whose GL its clearing relief will credit. Null only when the check has no resolvable drawee AND carries no snapshot. cleared_link_source: type: string nullable: true readOnly: true enum: - forward_stamp - reverse_link description: > RETRIEVE ONLY. WHICH pairing answered for `cleared_bank_txn_id`: `forward_stamp` is the check's own column (written by the clear that relieved it) and `reverse_link` is the bank row pointing back at the check. Null when nothing pairs. cleared_link_conflict: type: boolean readOnly: true description: > RETRIEVE ONLY. True when the check names one bank line AND a DIFFERENT bank row also points at this check. Two lines claiming one check is the shape of a double relief, so it is surfaced rather than silently resolved; `cleared_bank_txn_id` still answers with the forward stamp. cleared_bank_date: type: string format: date nullable: true readOnly: true description: >- RETRIEVE ONLY. The resolved bank line's own transaction date: the day the relief is dated when this line drives the clear. cleared_bank_amount: type: number nullable: true readOnly: true description: >- RETRIEVE ONLY. The resolved bank line's signed amount, so a caller can compare it with the check before clearing. cleared_bank_description: type: string nullable: true readOnly: true description: >- RETRIEVE ONLY. The resolved bank line's description as the bank sent it. 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.