> ## Documentation Index
> Fetch the complete documentation index at: https://docs.paypathiq.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Record an immutable WriteOff

> Requires financial_corrections:write. The type must match the resource family. Credits and write-offs decrease balances; adjustments declare their direction. Exact retries are safe; changed identities and stale source revisions conflict. These operations do not collect money or initiate refunds.



## OpenAPI

````yaml /generated/inbound-api-v1.openapi.json put /v1/clients/{clientCode}/write-offs/{externalEventId}
openapi: 3.1.0
info:
  description: >-
    Send Customers, Receivables, and Payment observations and related financial
    evidence from your source system to PayPathIQ, one record at a time or as
    bounded asynchronous batches, and read back changes. Every operation listed
    here is implemented; capabilities that are not implemented are not listed.
    Start in sandbox with a sandbox key and synthetic data. Every error type
    links to a page at https://docs.paypathiq.com/problems/{code}.
  title: PayPathIQ Inbound Receivables API
  version: 1.0.0
servers:
  - description: Sandbox
    url: https://api.sandbox.paypathiq.com
  - description: Production
    url: https://api.paypathiq.com
security:
  - BearerAuth: []
tags:
  - description: >-
      PayPathIQ-owned delivery of receipts to the accounting Source, with
      acknowledgement kept separate.
    name: Receipt delivery
  - description: People and businesses that owe one Client.
    name: Customers
  - description: Independently recoverable Receivables.
    name: Receivables
  - description: Immutable evidence of external payments, refunds, and reversals.
    name: Payment observations
  - description: >-
      Ordered Source balance snapshots for transaction and snapshot-only
      connections.
    name: Balance snapshots
  - description: >-
      Bounded asynchronous ingestion of up to 100 records with exact per-record
      outcomes.
    name: Batches
  - description: >-
      Verified complete-book declarations that flag and hold Receivables missing
      from the book.
    name: Complete books
  - description: Durable, resumable record of committed Customer and Receivable changes.
    name: Changes
  - description: >-
      Optional signed, minimal notifications that a Customer or Receivable
      changed.
    name: Webhooks
  - description: >-
      Fixed-amount hosted payment pages through the Client's own payment
      provider merchant.
    name: Payment requests
  - description: >-
      Partner-owned delivery of confirmed Payments to accounting, kept separate
      from accounting acceptance.
    name: Payment delivery
  - description: Explicit Receivable pause and closure commands.
    name: Receivable lifecycle
  - description: >-
      Explicit, revisioned instructions that let PayPathIQ begin recovery for a
      Receivable.
    name: Recovery instructions
  - description: >-
      Permissioned working collection position, holds, commitments and action
      outcomes, separate from the Source representation.
    name: Collection summaries
  - description: Whether accepted source evidence is recent enough to act on.
    name: Source freshness
  - description: This machine-readable API contract.
    name: Specification
paths:
  /v1/clients/{clientCode}/write-offs/{externalEventId}:
    put:
      summary: Record an immutable WriteOff
      description: >-
        Requires financial_corrections:write. The type must match the resource
        family. Credits and write-offs decrease balances; adjustments declare
        their direction. Exact retries are safe; changed identities and stale
        source revisions conflict. These operations do not collect money or
        initiate refunds.
      operationId: putWriteOff
      parameters:
        - name: clientCode
          in: path
          required: true
          schema:
            type: string
            pattern: ^[A-Za-z0-9_-]{1,128}$
        - name: externalEventId
          in: path
          required: true
          schema:
            type: string
            pattern: ^[A-Za-z0-9_-]{1,128}$
      requestBody:
        description: One uncompressed resource representation, limited to 256 KiB.
        content:
          application/json:
            example:
              type: write_off
              amount:
                amount: '10.00'
                currency: EUR
              externalReceivableId: REC_EXAMPLE
              sourceRevision: 2
              effectiveAt: '2026-10-14T12:00:00Z'
              reason: approved_write_off
              sourceReference: CREDIT_SOURCE
            schema:
              $ref: '#/components/schemas/WriteOff'
        required: true
      responses:
        '200':
          content:
            application/json:
              example:
                type: write_off
                amount:
                  amount: '10.00'
                  currency: EUR
                externalReceivableId: REC_EXAMPLE
                sourceRevision: 2
                effectiveAt: '2026-10-14T12:00:00Z'
                reason: approved_write_off
                sourceReference: CREDIT_SOURCE
                externalEventId: EVENT_EXAMPLE
                acceptedAt: '2026-10-14T12:00:01Z'
              schema:
                $ref: '#/components/schemas/WriteOffResponse'
          description: Identical safe retry.
          headers:
            Cache-Control:
              description: Integration-facing responses are never cached.
              schema:
                const: no-store
                type: string
            PayPathIQ-Api-Version:
              description: >-
                Public API contract version; industry profile is fixed by the
                current Integration grant.
              schema:
                type: string
                const: v1
            X-Request-Id:
              description: PayPathIQ-generated support correlation identifier.
              schema:
                format: uuid
                type: string
        '201':
          content:
            application/json:
              example:
                type: write_off
                amount:
                  amount: '10.00'
                  currency: EUR
                externalReceivableId: REC_EXAMPLE
                sourceRevision: 2
                effectiveAt: '2026-10-14T12:00:00Z'
                reason: approved_write_off
                sourceReference: CREDIT_SOURCE
                externalEventId: EVENT_EXAMPLE
                acceptedAt: '2026-10-14T12:00:01Z'
              schema:
                $ref: '#/components/schemas/WriteOffResponse'
          description: Evidence and balance committed atomically.
          headers:
            Cache-Control:
              description: Integration-facing responses are never cached.
              schema:
                const: no-store
                type: string
            PayPathIQ-Api-Version:
              description: >-
                Public API contract version; industry profile is fixed by the
                current Integration grant.
              schema:
                type: string
                const: v1
            X-Request-Id:
              description: PayPathIQ-generated support correlation identifier.
              schema:
                format: uuid
                type: string
            Location:
              description: Canonical URL of the created Integration-facing resource.
              schema:
                type: string
                format: uri
        '400':
          content:
            application/problem+json:
              examples:
                malformed_json:
                  value:
                    detail: Request body is not valid JSON.
                    requestId: 29400000-0000-4000-8000-000000000001
                    status: 400
                    title: Request body is not valid JSON.
                    type: https://docs.paypathiq.com/problems/malformed_json
              schema:
                $ref: '#/components/schemas/Problem'
          description: Request body is not valid JSON.
          headers:
            Cache-Control:
              description: Integration-facing responses are never cached.
              schema:
                const: no-store
                type: string
            PayPathIQ-Api-Version:
              description: >-
                Public API contract version; industry profile is fixed by the
                current Integration grant.
              schema:
                type: string
                const: v1
            X-Request-Id:
              description: PayPathIQ-generated support correlation identifier.
              schema:
                format: uuid
                type: string
        '401':
          content:
            application/problem+json:
              examples:
                invalid_api_key:
                  value:
                    detail: >-
                      API key is invalid, inactive, revoked, or for another
                      environment.
                    requestId: 29400000-0000-4000-8000-000000000001
                    status: 401
                    title: >-
                      API key is invalid, inactive, revoked, or for another
                      environment.
                    type: https://docs.paypathiq.com/problems/invalid_api_key
              schema:
                $ref: '#/components/schemas/Problem'
          description: API key is invalid, inactive, revoked, or for another environment.
          headers:
            Cache-Control:
              description: Integration-facing responses are never cached.
              schema:
                const: no-store
                type: string
            PayPathIQ-Api-Version:
              description: >-
                Public API contract version; industry profile is fixed by the
                current Integration grant.
              schema:
                type: string
                const: v1
            X-Request-Id:
              description: PayPathIQ-generated support correlation identifier.
              schema:
                format: uuid
                type: string
        '403':
          content:
            application/problem+json:
              examples:
                client_scope_denied:
                  value:
                    detail: >-
                      The Client code is unknown, the grant lacks the required
                      scope, or the calling address is outside the grant's IP
                      allowlist.
                    requestId: 29400000-0000-4000-8000-000000000001
                    status: 403
                    title: >-
                      The Client code is unknown, the grant lacks the required
                      scope, or the calling address is outside the grant's IP
                      allowlist.
                    type: https://docs.paypathiq.com/problems/client_scope_denied
              schema:
                $ref: '#/components/schemas/Problem'
          description: >-
            The Client code is unknown, the grant lacks the required scope, or
            the calling address is outside the grant's IP allowlist.
          headers:
            Cache-Control:
              description: Integration-facing responses are never cached.
              schema:
                const: no-store
                type: string
            PayPathIQ-Api-Version:
              description: >-
                Public API contract version; industry profile is fixed by the
                current Integration grant.
              schema:
                type: string
                const: v1
            X-Request-Id:
              description: PayPathIQ-generated support correlation identifier.
              schema:
                format: uuid
                type: string
        '409':
          content:
            application/problem+json:
              examples:
                financial_operation_required:
                  value:
                    detail: >-
                      The connection declares snapshot balance authority; event
                      balance writes are unavailable.
                    requestId: 29400000-0000-4000-8000-000000000001
                    status: 409
                    title: >-
                      The connection declares snapshot balance authority; event
                      balance writes are unavailable.
                    type: >-
                      https://docs.paypathiq.com/problems/financial_operation_required
                financial_event_conflict:
                  value:
                    detail: Identity already has different immutable evidence.
                    requestId: 29400000-0000-4000-8000-000000000001
                    status: 409
                    title: Identity already has different immutable evidence.
                    type: >-
                      https://docs.paypathiq.com/problems/financial_event_conflict
                source_revision_conflict:
                  value:
                    detail: Source revision is not newer than the accepted position.
                    requestId: 29400000-0000-4000-8000-000000000001
                    status: 409
                    title: Source revision is not newer than the accepted position.
                    type: >-
                      https://docs.paypathiq.com/problems/source_revision_conflict
                dependency_missing:
                  value:
                    detail: The source Receivable must already exist.
                    requestId: 29400000-0000-4000-8000-000000000001
                    status: 409
                    title: The source Receivable must already exist.
                    type: https://docs.paypathiq.com/problems/dependency_missing
                balance_mismatch:
                  value:
                    detail: The financial effect exceeds the supported balance bounds.
                    requestId: 29400000-0000-4000-8000-000000000001
                    status: 409
                    title: The financial effect exceeds the supported balance bounds.
                    type: https://docs.paypathiq.com/problems/balance_mismatch
              schema:
                $ref: '#/components/schemas/Problem'
          description: >-
            The connection declares snapshot balance authority; event balance
            writes are unavailable. Identity already has different immutable
            evidence. Source revision is not newer than the accepted position.
            The source Receivable must already exist. The financial effect
            exceeds the supported balance bounds.
          headers:
            Cache-Control:
              description: Integration-facing responses are never cached.
              schema:
                const: no-store
                type: string
            PayPathIQ-Api-Version:
              description: >-
                Public API contract version; industry profile is fixed by the
                current Integration grant.
              schema:
                type: string
                const: v1
            X-Request-Id:
              description: PayPathIQ-generated support correlation identifier.
              schema:
                format: uuid
                type: string
        '413':
          content:
            application/problem+json:
              examples:
                request_too_large:
                  value:
                    detail: Request body exceeds the 256 KiB resource limit.
                    requestId: 29400000-0000-4000-8000-000000000001
                    status: 413
                    title: Request body exceeds the 256 KiB resource limit.
                    type: https://docs.paypathiq.com/problems/request_too_large
              schema:
                $ref: '#/components/schemas/Problem'
          description: Request body exceeds the 256 KiB resource limit.
          headers:
            Cache-Control:
              description: Integration-facing responses are never cached.
              schema:
                const: no-store
                type: string
            PayPathIQ-Api-Version:
              description: >-
                Public API contract version; industry profile is fixed by the
                current Integration grant.
              schema:
                type: string
                const: v1
            X-Request-Id:
              description: PayPathIQ-generated support correlation identifier.
              schema:
                format: uuid
                type: string
        '415':
          content:
            application/problem+json:
              examples:
                unsupported_media_type:
                  value:
                    detail: >-
                      Media type or content encoding is unsupported. Send
                      uncompressed application/json for PUT and POST, and
                      application/merge-patch+json for PATCH.
                    requestId: 29400000-0000-4000-8000-000000000001
                    status: 415
                    title: >-
                      Media type or content encoding is unsupported. Send
                      uncompressed application/json for PUT and POST, and
                      application/merge-patch+json for PATCH.
                    type: https://docs.paypathiq.com/problems/unsupported_media_type
              schema:
                $ref: '#/components/schemas/Problem'
          description: >-
            Media type or content encoding is unsupported. Send uncompressed
            application/json for PUT and POST, and application/merge-patch+json
            for PATCH.
          headers:
            Cache-Control:
              description: Integration-facing responses are never cached.
              schema:
                const: no-store
                type: string
            PayPathIQ-Api-Version:
              description: >-
                Public API contract version; industry profile is fixed by the
                current Integration grant.
              schema:
                type: string
                const: v1
            X-Request-Id:
              description: PayPathIQ-generated support correlation identifier.
              schema:
                format: uuid
                type: string
        '422':
          content:
            application/problem+json:
              examples:
                validation_error:
                  value:
                    detail: >-
                      Route parameters or the representation are invalid. Route
                      parameters are checked before authentication. Field errors
                      carry a code such as invalid_format, unrecognized_keys,
                      custom, sensitive_external_id, or
                      sensitive_source_reference.
                    errors:
                      - code: invalid_format
                        detail: Invalid ISO date
                        pointer: /dueDate
                    requestId: 29400000-0000-4000-8000-000000000001
                    status: 422
                    title: >-
                      Route parameters or the representation are invalid. Route
                      parameters are checked before authentication. Field errors
                      carry a code such as invalid_format, unrecognized_keys,
                      custom, sensitive_external_id, or
                      sensitive_source_reference.
                    type: https://docs.paypathiq.com/problems/validation_error
              schema:
                $ref: '#/components/schemas/Problem'
          description: >-
            Route parameters or the representation are invalid. Route parameters
            are checked before authentication. Field errors carry a code such as
            invalid_format, unrecognized_keys, custom, sensitive_external_id, or
            sensitive_source_reference.
          headers:
            Cache-Control:
              description: Integration-facing responses are never cached.
              schema:
                const: no-store
                type: string
            PayPathIQ-Api-Version:
              description: >-
                Public API contract version; industry profile is fixed by the
                current Integration grant.
              schema:
                type: string
                const: v1
            X-Request-Id:
              description: PayPathIQ-generated support correlation identifier.
              schema:
                format: uuid
                type: string
        '429':
          content:
            application/problem+json:
              examples:
                rate_limit_exceeded:
                  value:
                    detail: >-
                      Each API key may send 60 requests per minute and run 1
                      request at a time. In sandbox, the same limits also apply
                      per Client across all of its keys. Every request,
                      including GET, counts.
                    requestId: 29400000-0000-4000-8000-000000000001
                    status: 429
                    title: >-
                      Each API key may send 60 requests per minute and run 1
                      request at a time. In sandbox, the same limits also apply
                      per Client across all of its keys. Every request,
                      including GET, counts.
                    type: https://docs.paypathiq.com/problems/rate_limit_exceeded
              schema:
                $ref: '#/components/schemas/Problem'
          description: >-
            Each API key may send 60 requests per minute and run 1 request at a
            time. In sandbox, the same limits also apply per Client across all
            of its keys. Every request, including GET, counts.
          headers:
            Cache-Control:
              description: Integration-facing responses are never cached.
              schema:
                const: no-store
                type: string
            PayPathIQ-Api-Version:
              description: >-
                Public API contract version; industry profile is fixed by the
                current Integration grant.
              schema:
                type: string
                const: v1
            X-Request-Id:
              description: PayPathIQ-generated support correlation identifier.
              schema:
                format: uuid
                type: string
            Retry-After:
              description: >-
                Seconds until this unchanged request may be retried: 1 after a
                concurrency rejection, 60 after the per-minute limit.
              schema:
                minimum: 1
                type: integer
        '503':
          content:
            application/problem+json:
              examples:
                projection_unavailable:
                  value:
                    detail: >-
                      An unexpected error prevented a safe commit, and nothing
                      was saved. Retry with backoff.
                    requestId: 29400000-0000-4000-8000-000000000001
                    status: 503
                    title: >-
                      An unexpected error prevented a safe commit, and nothing
                      was saved. Retry with backoff.
                    type: https://docs.paypathiq.com/problems/projection_unavailable
              schema:
                $ref: '#/components/schemas/Problem'
          description: >-
            An unexpected error prevented a safe commit, and nothing was saved.
            Retry with backoff.
          headers:
            Cache-Control:
              description: Integration-facing responses are never cached.
              schema:
                const: no-store
                type: string
            PayPathIQ-Api-Version:
              description: >-
                Public API contract version; industry profile is fixed by the
                current Integration grant.
              schema:
                type: string
                const: v1
            X-Request-Id:
              description: PayPathIQ-generated support correlation identifier.
              schema:
                format: uuid
                type: string
      security:
        - BearerAuth: []
components:
  schemas:
    WriteOff:
      type: object
      properties:
        amount:
          type: object
          properties:
            amount:
              type: string
              pattern: ^(0|[1-9]\d{0,13})\.\d{2}$
            currency:
              type: string
              const: EUR
          required:
            - amount
            - currency
          additionalProperties: false
        externalReceivableId:
          type: string
          pattern: ^[A-Za-z0-9_-]{1,128}$
        sourceRevision:
          type: integer
          exclusiveMinimum: 0
          maximum: 9007199254740991
        effectiveAt:
          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))$
        reason:
          type: string
          const: approved_write_off
        sourceReference:
          type: string
          minLength: 1
          maxLength: 200
        type:
          type: string
          const: write_off
      required:
        - amount
        - externalReceivableId
        - sourceRevision
        - effectiveAt
        - reason
        - sourceReference
        - type
      additionalProperties: false
    WriteOffResponse:
      type: object
      properties:
        amount:
          type: object
          properties:
            amount:
              type: string
              pattern: ^(0|[1-9]\d{0,13})\.\d{2}$
            currency:
              type: string
              const: EUR
          required:
            - amount
            - currency
          additionalProperties: false
        externalReceivableId:
          type: string
          pattern: ^[A-Za-z0-9_-]{1,128}$
        sourceRevision:
          type: integer
          exclusiveMinimum: 0
          maximum: 9007199254740991
        effectiveAt:
          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))$
        reason:
          type: string
          const: approved_write_off
        sourceReference:
          type: string
          minLength: 1
          maxLength: 200
        type:
          type: string
          const: write_off
        externalEventId:
          type: string
          pattern: ^[A-Za-z0-9_-]{1,128}$
        acceptedAt:
          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))$
      required:
        - amount
        - externalReceivableId
        - sourceRevision
        - effectiveAt
        - reason
        - sourceReference
        - type
        - externalEventId
        - acceptedAt
      additionalProperties: false
    Problem:
      type: object
      properties:
        detail:
          type: string
        errors:
          maxItems: 20
          type: array
          items:
            type: object
            properties:
              code:
                type: string
              detail:
                type: string
              pointer:
                type: string
            required:
              - code
              - detail
              - pointer
            additionalProperties: false
        requestId:
          type: string
          format: uuid
          pattern: >-
            ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$
        status:
          type: integer
          minimum: 400
          maximum: 599
        title:
          type: string
        type:
          type: string
          format: uri
      required:
        - detail
        - requestId
        - status
        - title
        - type
      additionalProperties: false
  securitySchemes:
    BearerAuth:
      bearerFormat: ppiq_test_<keyId>_<secret> or ppiq_live_<keyId>_<secret>
      description: >-
        Integration-owned environment-specific API key. Never paste a production
        key into documentation tools.
      scheme: bearer
      type: http

````

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