> ## Documentation Index > Fetch the complete documentation index at: https://docs.bachs.io/llms.txt > Use this file to discover all available pages before exploring further. > ## Agent Instructions > Money is always a decimal string at the currency's precision (for example "29.00"), paired with an ISO 4217 currency field. Never use minor units. > Build against the sandbox first: base URL https://sandbox-api.bachs.io with sk_sandbox_ keys. Production is https://api.bachs.io with sk_live_ keys; going live is a key swap. > Treat webhooks (for example collection.succeeded) as the source of truth for fulfilment, never client-side events or redirects. > Subscriptions are created by completing a checkout for a recurring product. There is no direct create-subscription endpoint. > IDs carry resource prefixes (cust_, prod_, sub_, chk_, inv_, ref_) and timestamps are ISO 8601 UTC. # Update Dispute Evidence > Save or update dispute evidence fields before final submission. Evidence can be updated iteratively while the dispute remains editable. ## OpenAPI ````yaml /docs/openapi/openapi.json patch /v1/disputes/{dispute_id}/evidence openapi: 3.0.3 info: title: Bachs API version: 1.0.0 description: >- The Bachs API lets you accept payments, manage subscriptions, and move money across African markets. - **Authentication:** pass your secret key as `Authorization: Bearer sk_...`. See [Authentication](/authentication) for keys, scopes, and sandbox vs production. - **Errors:** errors use `detail` and `error_code`; `doc_url` and field-level `errors` are optional. See [Errors](/errors). - **Pagination:** list endpoints return `{ items, pagination }`. See [Pagination](/guides/pagination). - **Idempotency:** use `Idempotency-Key` on public `POST` and `PATCH`; reconcile uncertain write outcomes before retrying. See [Idempotency](/guides/idempotency). - **Base URLs and rate limits:** see the [Introduction](/api-reference/overview). contact: name: Bachs Support url: https://bachs.io servers: - url: https://api.bachs.io description: Production - url: https://sandbox-api.bachs.io description: Sandbox security: - ApiKeyAuth: [] tags: - name: Payments description: Accept payments from customers - name: Refunds description: Create and manage customer refunds - name: Disputes description: Respond to chargebacks and manage dispute evidence - name: Balances description: View balances and account information - name: Conversions description: Quote, execute, and query currency conversions - name: Payouts description: Withdraw funds to external accounts - name: Webhooks description: Receive real-time payment notifications - name: Authentication description: API key management and authentication - name: Customers description: Create and manage customers - name: Products description: Define and manage your billing catalog - name: Product Groups description: Bundle products for multi-plan checkout - name: Media description: Upload files and get an upload_id to attach to products - name: Checkouts description: Create and manage API-driven checkouts without products - name: Subscriptions description: >- Recurring billing. Subscriptions are created through checkout; manage them here. - name: Customer sessions description: >- Open a hosted portal session so a customer can manage their own subscriptions, invoices and cards. - name: Accounts description: >- Create the accounts your platform onboards, request their capabilities, walk them through their requirements, and read what they still owe. - name: Transfers description: Move funds between your platform and the accounts you own. - name: Platform Fees description: Read the platform's cut of an account's sale. - name: Virtual Accounts description: Create and read fixed bank account numbers for receiving deposits. paths: /v1/disputes/{dispute_id}/evidence: patch: tags: - Disputes summary: Update Dispute Evidence description: >- Save or update dispute evidence fields before final submission. Evidence can be updated iteratively while the dispute remains editable. operationId: updateDisputeEvidence parameters: - name: dispute_id in: path required: true description: Unique identifier for the dispute. schema: type: string requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/DisputeEvidenceUpdateRequest' example: customer_name: Amara Osei customer_email_address: customer@example.com product_description: Annual SaaS subscription, plan ID PLAN-PRO-001 service_date: '2026-03-01' notes: Customer confirmed delivery via email on March 5. customer_communication_attachment_id: upl_9f2c7b3d1e45 responses: '200': description: Evidence updated successfully. content: application/json: schema: $ref: '#/components/schemas/DisputeEvidenceUpdateResponse' example: dispute_id: dsp_3e7b1c9a2f48 status: needs_response is_response_editable: true evidence_updated_at: '2026-03-09T11:30:00.000Z' '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/Unauthorized' '403': $ref: '#/components/responses/Forbidden' '404': $ref: '#/components/responses/NotFound' '409': $ref: '#/components/responses/Conflict' '429': $ref: '#/components/responses/TooManyRequests' '500': $ref: '#/components/responses/InternalServerError' security: - ApiKeyAuth: [] components: schemas: DisputeEvidenceUpdateRequest: type: object description: >- Fields used to create or update dispute evidence. Include only fields that should change. properties: access_activity_log: type: string description: >- An access or activity log showing the customer used what they paid for. billing_address: type: string description: Customer's billing address. cancellation_policy_attachment_id: type: string description: Upload id of your cancellation policy document. cancellation_policy_disclosure: type: string description: Cancellation policy shown to the customer. customer_communication_attachment_id: type: string description: Uploaded customer communication document identifier. customer_email_address: type: string description: Email address of the customer. customer_name: type: string description: Full name of the customer. notes: type: string description: Additional context supporting the dispute response. product_description: type: string description: Description of delivered goods or services. refund_policy_attachment_id: type: string description: Upload id of your refund policy document. refund_policy_disclosure: type: string description: Refund policy shown to the customer. refund_refusal_explanation: type: string description: Reason a refund was not granted. service_date: type: string description: Date the service was delivered. uncategorized_attachment_id: type: string description: Uploaded supporting document identifier. DisputeEvidenceUpdateResponse: type: object description: Response after saving dispute evidence fields. properties: dispute_id: type: string description: The dispute that was updated. status: type: string description: Current dispute status after update. is_response_editable: type: boolean description: Whether the dispute is still editable after update. evidence_updated_at: type: string format: date-time description: Timestamp when evidence was last updated. required: - dispute_id - status - is_response_editable - evidence_updated_at Error: type: object description: Standard error response format used across all API endpoints properties: detail: type: string description: Human-readable error message explaining what went wrong. example: Invalid request parameters error_code: type: string description: >- Machine-readable error code. Use this to handle errors programmatically. Common codes: VALIDATION_ERROR, UNAUTHORIZED, FORBIDDEN, NOT_FOUND, CONFLICT, TOO_MANY_REQUESTS, INTERNAL_SERVER_ERROR, BAD_GATEWAY, SERVICE_UNAVAILABLE. example: VALIDATION_ERROR errors: type: array description: >- Optional field-level details on some validation errors. Other validation responses contain only detail and error_code. Entry fields depend on the validation source. items: type: object properties: field: type: string description: The field that failed validation. example: amount message: type: string description: Description of the validation failure. example: Amount must be a positive decimal string type: type: string description: Error type identifier. example: value_error code: type: string description: >- Optional requirement-field rejection code. Some validation entries provide code instead of type. example: currency_not_supported required: - field - message doc_url: type: string description: Optional link to documentation for this error; some errors omit it. example: https://docs.bachs.io/api-reference/error-reference#general required: - detail - error_code responses: BadRequest: description: >- Bad Request - Validation errors or invalid request format. Check the `details` object for field-specific validation errors. Common causes: missing required fields, invalid data types, values outside allowed ranges, or invalid formats. content: application/json: schema: $ref: '#/components/schemas/Error' example: detail: Invalid request parameters error_code: VALIDATION_ERROR errors: - field: amount message: Amount must be a positive decimal string type: value_error headers: X-RateLimit-Limit: description: Maximum number of requests allowed per minute schema: type: integer example: 100 X-RateLimit-Remaining: description: Number of requests remaining in the current window schema: type: integer example: 95 X-RateLimit-Reset: description: Unix timestamp when the rate limit window resets schema: type: integer example: 1706102400 Unauthorized: description: >- Unauthorized - Invalid, missing, or expired API key. Verify your API key is correctly formatted and included in the Authorization header as `Bearer sk_sandbox_...` or `Bearer sk_live_...`. Check that your key hasn't been revoked. content: application/json: schema: $ref: '#/components/schemas/Error' example: detail: Invalid API key error_code: UNAUTHORIZED headers: X-RateLimit-Limit: description: Maximum number of requests allowed per minute schema: type: integer example: 100 X-RateLimit-Remaining: description: Number of requests remaining in the current window schema: type: integer example: 95 X-RateLimit-Reset: description: Unix timestamp when the rate limit window resets schema: type: integer example: 1706102400 Forbidden: description: >- Forbidden - API key does not have permission for the requested resource. Verify you're using the correct account's API key and that you're not trying to access another account's data. content: application/json: schema: $ref: '#/components/schemas/Error' example: detail: API key does not have permission for this operation error_code: FORBIDDEN headers: X-RateLimit-Limit: description: Maximum number of requests allowed per minute schema: type: integer example: 100 X-RateLimit-Remaining: description: Number of requests remaining in the current window schema: type: integer example: 95 X-RateLimit-Reset: description: Unix timestamp when the rate limit window resets schema: type: integer example: 1706102400 NotFound: description: >- Not Found - The requested resource does not exist. Verify the resource ID is correct and that it belongs to your account. content: application/json: schema: $ref: '#/components/schemas/Error' example: detail: Resource not found error_code: NOT_FOUND headers: X-RateLimit-Limit: description: Maximum number of requests allowed per minute schema: type: integer example: 100 X-RateLimit-Remaining: description: Number of requests remaining in the current window schema: type: integer example: 95 X-RateLimit-Reset: description: Unix timestamp when the rate limit window resets schema: type: integer example: 1706102400 Conflict: description: >- Conflict - Duplicate request detected (idempotency). This occurs when the same request is made multiple times with the same idempotency key. The original request's response is returned. content: application/json: schema: $ref: '#/components/schemas/Error' example: detail: Duplicate request detected error_code: CONFLICT headers: X-RateLimit-Limit: description: Maximum number of requests allowed per minute schema: type: integer example: 100 X-RateLimit-Remaining: description: Number of requests remaining in the current window schema: type: integer example: 95 X-RateLimit-Reset: description: Unix timestamp when the rate limit window resets schema: type: integer example: 1706102400 TooManyRequests: description: >- Too Many Requests - Rate limit exceeded. Standard tier allows 100 requests per minute per API key. Wait a few seconds before retrying. Check X-RateLimit-Reset header for when the window resets. content: application/json: schema: $ref: '#/components/schemas/Error' example: detail: Rate limit exceeded. Please retry after a few seconds. error_code: TOO_MANY_REQUESTS headers: X-RateLimit-Limit: description: Maximum number of requests allowed per minute schema: type: integer example: 100 X-RateLimit-Remaining: description: Number of requests remaining in the current window (will be 0) schema: type: integer example: 0 X-RateLimit-Reset: description: Unix timestamp when the rate limit window resets schema: type: integer example: 1706102400 Retry-After: description: Number of seconds to wait before retrying schema: type: integer example: 30 InternalServerError: description: >- Internal Server Error - An unexpected error occurred while processing the request. Retry with exponential backoff. If the issue persists, contact support with your request context. content: application/json: schema: $ref: '#/components/schemas/Error' example: detail: An unexpected error occurred. Please try again later. error_code: INTERNAL_SERVER_ERROR headers: X-RateLimit-Limit: description: Maximum number of requests allowed per minute schema: type: integer example: 100 X-RateLimit-Remaining: description: Number of requests remaining in the current window schema: type: integer example: 95 X-RateLimit-Reset: description: Unix timestamp when the rate limit window resets schema: type: integer example: 1706102400 securitySchemes: ApiKeyAuth: type: http scheme: bearer bearerFormat: API Key description: >- Bearer token authentication. Pass your API key as `Authorization: Bearer sk_...`. See [Authentication](/authentication) for keys, scopes, and sandbox vs production. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.