> ## Documentation Index > Fetch the complete documentation index at: https://docs-pos.solya.app/llms.txt > Use this file to discover all available pages before exploring further. # Edit an existing coupon > REPLACES the terms of one existing coupon addressed by the path `id` (server-minted; resolve it through `GET /v1/coupons` — the `code` is what customers type, the `id` is what this takes). The body is the SAME shape as create: it overwrites `code`, `discount`, the validity window, `maxRedemptions` and `minBasketCents` wholesale — a field you omit is not preserved, it is replaced by the schema's value, so send the COMPLETE intended terms, not a partial patch. The path id is authoritative and the coupon's own `id` never changes; there is no `id` in the body to retarget. Editing does NOT reset the redemption ledger: the returned view keeps the live `redemptionCount`, and a lowered `maxRedemptions` can already be at or below the count (the cap is enforced at redemption, not here). Only ACTIVE coupons are editable — a deactivated coupon is terminal and 404s, exactly as it reads back everywhere else. 404s when no active coupon bears the id. ## OpenAPI ````yaml /openapi.json put /v1/coupons/{id} openapi: 3.0.3 info: title: Solya POS API version: 1.0.0 description: >- The Solya POS backend HTTP surface. Every documented operation is agent-ready: it carries an `operationId`, an agent-facing `description`, the `pos.*` scopes it enforces (`x-required-permissions`) and an `x-agent-tier`. Success responses return the payload as raw JSON; failures return the `ErrorResponse` envelope (`{ error: { code, message, statusCode } }`). servers: - url: / description: The backend, relative to its deployed origin. security: [] paths: /v1/coupons/{id}: put: tags: - Promotions summary: Edit an existing coupon description: >- REPLACES the terms of one existing coupon addressed by the path `id` (server-minted; resolve it through `GET /v1/coupons` — the `code` is what customers type, the `id` is what this takes). The body is the SAME shape as create: it overwrites `code`, `discount`, the validity window, `maxRedemptions` and `minBasketCents` wholesale — a field you omit is not preserved, it is replaced by the schema's value, so send the COMPLETE intended terms, not a partial patch. The path id is authoritative and the coupon's own `id` never changes; there is no `id` in the body to retarget. Editing does NOT reset the redemption ledger: the returned view keeps the live `redemptionCount`, and a lowered `maxRedemptions` can already be at or below the count (the cap is enforced at redemption, not here). Only ACTIVE coupons are editable — a deactivated coupon is terminal and 404s, exactly as it reads back everywhere else. 404s when no active coupon bears the id. operationId: updateCoupon parameters: - schema: type: string minLength: 1 in: path name: id required: true requestBody: required: true content: application/json: schema: type: object properties: code: type: string minLength: 1 discount: oneOf: - type: object properties: type: type: string enum: - percentage rateBps: type: integer minimum: 0 exclusiveMinimum: true maximum: 10000 required: - type - rateBps - type: object properties: type: type: string enum: - fixed amountCents: type: integer minimum: 0 exclusiveMinimum: true maximum: 9007199254740991 required: - type - amountCents validFrom: type: string format: date-time pattern: >- ^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d(?::[0-5]\d(?:\.\d+)?)?(?:Z))$ validUntil: type: string format: date-time pattern: >- ^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d(?::[0-5]\d(?:\.\d+)?)?(?:Z))$ maxRedemptions: type: integer minimum: 0 exclusiveMinimum: true maximum: 9007199254740991 minBasketCents: type: integer minimum: 0 maximum: 9007199254740991 required: - code - discount - validFrom - validUntil - maxRedemptions - minBasketCents example: code: SAVE10 discount: type: percentage rateBps: 1000 validFrom: '2026-01-01T00:00:00.000Z' validUntil: '2026-12-31T23:59:59.000Z' maxRedemptions: 5 minBasketCents: 0 responses: '200': description: >- The edited coupon, still active, with its unchanged id and ledger count. content: application/json: schema: type: object properties: id: type: string minLength: 1 code: type: string minLength: 1 discount: oneOf: - type: object properties: type: type: string enum: - percentage rateBps: type: integer minimum: 0 exclusiveMinimum: true maximum: 10000 required: - type - rateBps additionalProperties: false - type: object properties: type: type: string enum: - fixed amountCents: type: integer minimum: 0 exclusiveMinimum: true maximum: 9007199254740991 required: - type - amountCents additionalProperties: false validFrom: type: string format: date-time pattern: >- ^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d(?::[0-5]\d(?:\.\d+)?)?(?:Z))$ validUntil: type: string format: date-time pattern: >- ^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d(?::[0-5]\d(?:\.\d+)?)?(?:Z))$ maxRedemptions: type: integer minimum: 0 exclusiveMinimum: true maximum: 9007199254740991 minBasketCents: type: integer minimum: 0 maximum: 9007199254740991 active: type: boolean redemptionCount: type: integer minimum: 0 maximum: 9007199254740991 required: - id - code - discount - validFrom - validUntil - maxRedemptions - minBasketCents - active - redemptionCount additionalProperties: false description: >- The edited coupon, still active, with its unchanged id and ledger count. example: id: cpn-7f3a91c2 code: SAVE10 discount: type: percentage rateBps: 1000 validFrom: '2026-01-01T00:00:00.000Z' validUntil: '2026-12-31T23:59:59.000Z' maxRedemptions: 5 minBasketCents: 0 active: true redemptionCount: 0 '400': description: >- The request failed schema validation; `error.fieldErrors` lists the fields. content: application/json: schema: $ref: '#/components/schemas/ValidationErrorResponse' '401': description: No valid credential was presented — send a bearer token. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '403': description: The actor is authenticated but lacks the required `pos.*` scope. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '404': description: No resource matches the addressed identifier. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '500': description: An unexpected server error — safe to retry idempotent requests. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' security: - bearerAuth: [] components: schemas: ValidationErrorResponse: type: object required: - error additionalProperties: false description: >- A `VALIDATION_FAILED` envelope carrying the offending fields in `fieldErrors`. properties: error: type: object required: - code - message - statusCode additionalProperties: false properties: code: type: string enum: - VALIDATION_FAILED message: type: string statusCode: type: integer fieldErrors: type: array description: >- One entry per rejected field: the field path and why it was rejected. items: type: object required: - field - message additionalProperties: false properties: field: type: string description: Dot-path of the offending field. message: type: string description: Why the field was rejected. ErrorResponse: type: object required: - error additionalProperties: false description: The uniform failure envelope every non-2xx response returns. properties: error: type: object required: - code - message - statusCode additionalProperties: false properties: code: type: string enum: - VALIDATION_FAILED - UNAUTHORIZED - FORBIDDEN - NOT_FOUND - CONFLICT - BUSINESS_RULE_VIOLATION - INTERNAL_ERROR description: >- Machine-readable kernel `ResultCode` — branch on this, not on `message`. message: type: string description: >- Human-readable explanation. Safe to surface; never leaks server internals. statusCode: type: integer description: >- The HTTP status, mirrored into the body so a client need not read headers. securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: JWT description: >- `Authorization: Bearer `. Accepts EITHER a Keycloak access token (scopes-in-token) OR an opaque POS session token; both resolve to the same `pos.*` scope vocabulary the route guards enforce. ````