> ## Documentation Index > Fetch the complete documentation index at: https://docs.cope.com/llms.txt > Use this file to discover all available pages before exploring further. # List a subscription's price and plan change attempts > Every attempt to change this subscription's recurring amount (`price`) or to move it to another plan (`plan`), newest first, whether it was applied or refused. A refused attempt is recorded too and reads `status: failed` with a `failure` saying what stopped it, so an empty list means no amount or plan change has ever been attempted. **Pause, resume and cancel are not in this list.** Each of those three operations returns the subscription it leaves behind, and so does `GET /v1/commerce/subscriptions/{id}`: `status` reads `paused` after a pause and `canceling` after a cancel of either mode, `paused_at` is set for as long as the subscription is paused and null once it is resumed, and `cancel_at` carries when the cancellation takes effect. An entry's `status` is the attempt's own, `processing` included while it is in flight; `failure` is present only on a `failed` entry. A change is the subscription's `pending_change` until a renewal bills its terms, and `effective_confirmed_at` records that renewal. ## OpenAPI ````yaml /api-reference/commerce-v1.openapi.json get /v1/commerce/subscriptions/{id}/changes openapi: 3.0.3 info: description: >- Public REST API for COPE vendor integrations. Authenticate with a COPE API key and call the endpoints described below. title: COPE Public API version: v1 servers: - description: Production url: https://api.cope.com security: - cope_sk: [] paths: /v1/commerce/subscriptions/{id}/changes: get: tags: - Subscriptions summary: List a subscription's price and plan change attempts description: >- Every attempt to change this subscription's recurring amount (`price`) or to move it to another plan (`plan`), newest first, whether it was applied or refused. A refused attempt is recorded too and reads `status: failed` with a `failure` saying what stopped it, so an empty list means no amount or plan change has ever been attempted. **Pause, resume and cancel are not in this list.** Each of those three operations returns the subscription it leaves behind, and so does `GET /v1/commerce/subscriptions/{id}`: `status` reads `paused` after a pause and `canceling` after a cancel of either mode, `paused_at` is set for as long as the subscription is paused and null once it is resumed, and `cancel_at` carries when the cancellation takes effect. An entry's `status` is the attempt's own, `processing` included while it is in flight; `failure` is present only on a `failed` entry. A change is the subscription's `pending_change` until a renewal bills its terms, and `effective_confirmed_at` records that renewal. operationId: commerce.subscriptions.changes.list parameters: - description: id public identifier. example: ps_A1b2C3d4E5f6 in: path name: id required: true schema: example: ps_A1b2C3d4E5f6 pattern: ^ps_[A-Za-z0-9]{8,32}$ type: string - description: >- Page number for paginated results. Values below 1 and non-numeric values are ignored and the first page is returned; a page past the last one returns the last page. in: query name: page required: false schema: minimum: 1 type: integer - description: >- Number of records per page. Defaults to 12; values above 25 are clamped to 25; values below 1 and non-numeric values are ignored and the default is used. in: query name: per_page required: false schema: maximum: 25 minimum: 1 type: integer responses: '200': content: application/json: schema: additionalProperties: false properties: data: items: additionalProperties: false properties: created_at: description: When the attempt was recorded. type: string effective_at: nullable: true type: string effective_confirmed_at: description: >- When a renewal billed this change: the boundary of the cycle that billed its new terms, recorded when that cycle is booked, on every payment method. `null` until one has — and for good on a change superseded before it billed. nullable: true type: string failure: additionalProperties: false description: >- Present only when `status` is `failed`: the code and the message saying why. nullable: true properties: code: type: string message: type: string required: - code - message type: object from: additionalProperties: false properties: amount_cents: type: integer currency: type: string plan: additionalProperties: false description: >- The plan this side's terms were sold on or switched to: a plan change's target on `to`, otherwise the plan the terms name. `null` when no recorded fact names one — for example, terms sold through an offer, a plan since deleted, or terms from before plans were recorded. nullable: true properties: id: example: plan_A1b2C3d4 pattern: ^plan_[A-Za-z0-9]{8,32}$ type: string object: enum: - payment_plan type: string required: - object - id type: object required: - plan - amount_cents - currency type: object reason: nullable: true type: string status: description: >- What became of the attempt. `succeeded`: it was applied. `failed`: it was refused, and `failure` carries the code and the message saying why — nothing changed. `processing`: it is still in flight. enum: - processing - succeeded - failed type: string to: additionalProperties: false properties: amount_cents: nullable: true type: integer currency: type: string plan: additionalProperties: false description: >- The plan this side's terms were sold on or switched to: a plan change's target on `to`, otherwise the plan the terms name. `null` when no recorded fact names one — for example, terms sold through an offer, a plan since deleted, or terms from before plans were recorded. nullable: true properties: id: example: plan_A1b2C3d4 pattern: ^plan_[A-Za-z0-9]{8,32}$ type: string object: enum: - payment_plan type: string required: - object - id type: object required: - plan - amount_cents - currency type: object type: description: >- Which change was attempted: `price` for the recurring amount, `plan` for a move to another plan. A pause, a resume and a cancel are not in this history — see the operation description. enum: - price - plan type: string required: - type - status - created_at - effective_at - effective_confirmed_at - reason - from - to type: object type: array pagination: additionalProperties: false properties: current_page: type: integer per_page: type: integer total_count: type: integer total_pages: type: integer required: - total_pages - current_page - per_page - total_count type: object required: - data - pagination type: object description: Successful response '400': content: application/problem+json: examples: unparsable_request: summary: Unparsable request value: code: invalid_request detail: >- The request could not be parsed. Check the query string and the request body. request_id: req_123 status: 400 title: Invalid Request type: https://docs.cope.com/errors/invalid_request schema: $ref: '#/components/schemas/PublicProblemDetail' description: Invalid request '401': content: application/problem+json: schema: $ref: '#/components/schemas/PublicProblemDetail' description: Missing or invalid bearer token '403': content: application/problem+json: schema: $ref: '#/components/schemas/PublicProblemDetail' description: Bearer token is not authorized for this route '404': content: application/problem+json: schema: $ref: '#/components/schemas/PublicProblemDetail' description: Resource not found security: - cope_sk: [] components: schemas: PublicProblemDetail: additionalProperties: false properties: code: type: string detail: nullable: true type: string errors: items: additionalProperties: false properties: code: type: string detail: type: string param: type: string required: - code - detail type: object type: array request_id: type: string status: type: integer title: type: string type: type: string required: - type - title - status - code - request_id type: object securitySchemes: cope_sk: description: >- Bearer credential for the public API: a live COPE API key (`ck_live_*`; keys issued earlier as `cope_sk_live_*` keep working). Dashboard sign-in tokens are not accepted. scheme: bearer type: http ````