> ## Documentation Index > Fetch the complete documentation index at: https://docs.aiinsurance.io/llms.txt > Use this file to discover all available pages before exploring further. # Get Policy Transaction > Returns a single policy transaction by ID, including its per-field deltas. Each delta describes a specific field change (add, remove, or overwrite) within a date range. Use this endpoint to inspect exactly what changed in a given transaction. **Required permission:** `company.policy:read` ## OpenAPI ````yaml /openapi/generated-external-api.yaml get /api/v1/external/companies/{companyId}/policies/{policyId}/transactions/{transactionId} openapi: 3.0.3 info: title: AI Insurance External API description: External API for AI Insurance platform version: 1.0.0 contact: email: support@aiinsurance.io servers: - url: https://app.aiinsurance.io description: Production security: - ApiKeyAuth: [] paths: /api/v1/external/companies/{companyId}/policies/{policyId}/transactions/{transactionId}: get: tags: - Field Model Policy Transactions summary: Get Policy Transaction description: > Returns a single policy transaction by ID, including its per-field deltas. Each delta describes a specific field change (add, remove, or overwrite) within a date range. Use this endpoint to inspect exactly what changed in a given transaction. **Required permission:** `company.policy:read` operationId: getPolicyTransaction parameters: - $ref: '#/components/parameters/companyId' - $ref: '#/components/parameters/policyIdPath' - $ref: '#/components/parameters/transactionId' responses: '200': description: Transaction with deltas content: application/json: schema: $ref: '#/components/schemas/FMV1PolicyTransactionResponse' examples: endorsementTransaction: summary: Endorsement transaction with deltas value: id: 550e8400-e29b-41d4-a716-446655440020 policyId: 550e8400-e29b-41d4-a716-446655440001 policyVersion: 2 action: ENDORSE effectiveDate: '2025-06-01' transactionTimestamp: '2025-05-28T14:30:00.000Z' createdAt: '2025-05-28T14:30:00.000Z' createdBy: 550e8400-e29b-41d4-a716-446655440090 deltas: - id: 550e8400-e29b-41d4-a716-446655440030 transactionId: 550e8400-e29b-41d4-a716-446655440020 startDate: '2025-06-01' endDate: '2026-01-01' path: policy.annualPremium action: Overwrite value: 95000 - id: 550e8400-e29b-41d4-a716-446655440031 transactionId: 550e8400-e29b-41d4-a716-446655440020 startDate: '2025-06-01' endDate: '2026-01-01' path: policy.fullTermPolicyBilling.policyPremium action: Overwrite value: 95000 - id: 550e8400-e29b-41d4-a716-446655440032 transactionId: 550e8400-e29b-41d4-a716-446655440020 startDate: '2025-06-01' endDate: '2026-01-01' path: policy.fullTermPolicyBilling.policyGrandTotal action: Overwrite value: 95500 newBusinessTransaction: summary: New business transaction with deltas value: id: 550e8400-e29b-41d4-a716-446655440010 policyId: 550e8400-e29b-41d4-a716-446655440001 policyVersion: 1 action: NEW_BUSINESS effectiveDate: '2025-01-01' transactionTimestamp: '2025-01-15T10:30:00.000Z' createdAt: '2025-01-15T10:30:00.000Z' createdBy: 550e8400-e29b-41d4-a716-446655440090 deltas: - id: 550e8400-e29b-41d4-a716-446655440040 transactionId: 550e8400-e29b-41d4-a716-446655440010 startDate: '2025-01-01' endDate: '2026-01-01' path: policy action: Overwrite value: annualPremium: 85000 fullTermPolicyBilling: policyPremium: 85000 policyTaxes: 0 policyFees: 500 policyGrandTotal: 85500 fullTermPolicyInfo: policyStatus: Active policyStartDate: year: 2025 month: 1 day: 1 timezone: America/New_York policyEndDate: year: 2026 month: 1 day: 1 timezone: America/New_York exposures: - id: 550e8400-e29b-41d4-a716-446655440010 exposureType: MedicalFacility bedCount: 120 '401': $ref: '#/components/responses/Unauthorized' '403': $ref: '#/components/responses/Forbidden' '404': description: Transaction or policy not found content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' examples: transactionNotFound: summary: Transaction not found value: error: code: NOT_FOUND message: >- Transaction 550e8400-e29b-41d4-a716-446655440099 not found for policy 550e8400-e29b-41d4-a716-446655440001 '500': $ref: '#/components/responses/InternalServerError' components: parameters: companyId: name: companyId in: path required: true schema: type: string format: uuid description: Company identifier policyIdPath: name: policyId in: path required: true schema: type: string format: uuid description: Policy identifier transactionId: name: transactionId in: path required: true schema: type: string format: uuid description: Transaction identifier schemas: FMV1PolicyTransactionResponse: type: object description: > A policy transaction in the transaction-based policy model. Each transaction represents an immutable change set (new business, endorsement, cancellation, reinstatement, or renewal) that produces a new policy version. required: - id - policyId - policyVersion - action - effectiveDate - transactionTimestamp - createdAt - createdBy properties: id: type: string format: uuid description: Transaction identifier policyId: type: string format: uuid description: Policy identifier policyVersion: type: integer description: Sequential version number produced by this transaction action: type: string enum: - NEW_BUSINESS - ENDORSE - CANCEL - REINSTATE - RENEW description: Type of transaction effectiveDate: type: string format: date description: When the transaction takes effect (ISO 8601) transactionTimestamp: type: string format: date-time description: When the business decision was made (ISO 8601) createdAt: type: string format: date-time description: When the transaction record was created (ISO 8601) createdBy: type: string nullable: true description: User ID who created the transaction (null if system-created) deltas: type: array description: | Per-field deltas that make up this transaction. Only present on the get-single-transaction endpoint. items: $ref: '#/components/schemas/PolicyTransactionDeltaResponse' ErrorResponse: type: object description: Standard error response for all external API endpoints required: - error properties: error: type: object required: - code - message properties: code: type: string description: Machine-readable error code example: VALIDATION_ERROR message: type: string description: Human-readable error message example: 'submissionId: Required field is missing' details: type: array description: Additional details for validation errors (field-level errors) items: type: object properties: field: type: string description: The field that caused the error example: submissionId message: type: string description: Description of the field error example: Required field is missing PolicyTransactionDeltaResponse: type: object description: > A per-field delta representing a single change applied by a policy transaction. Each delta targets a specific field path within a date range (segment window). required: - id - transactionId - startDate - endDate - path - action - value properties: id: type: string format: uuid description: Delta identifier transactionId: type: string format: uuid description: Transaction that produced this delta startDate: type: string format: date description: Start of the date range this delta applies to (ISO 8601) endDate: type: string format: date description: End of the date range this delta applies to (ISO 8601) path: type: string description: > Dot-separated field path within the policy data, always prefixed with `policy.`. Collection items use bracket notation with stable IDs (e.g., `policy.annualPremium`, `policy.exposures[exp-1].bedCount`, `policy.fullTermPolicyBilling.policyPremium`). For NEW_BUSINESS transactions, the path is simply `policy` representing the entire policy blob. action: type: string enum: - Add - Remove - Overwrite description: | Type of change: - `Add` — field was added (new value) - `Remove` — field was removed - `Overwrite` — field value was overwritten value: description: >- The value associated with this delta. For `Add` and `Overwrite`, this is the new value. For `Remove`, this is the value that was removed from the collection. responses: Unauthorized: description: Unauthorized - Invalid or missing API key content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' examples: missingApiKey: summary: Missing API key value: error: code: UNAUTHORIZED message: Authorization header is required bearerTokenNotAllowed: summary: Bearer token used instead of API key value: error: code: UNAUTHORIZED message: External API endpoints require API key authentication Forbidden: description: Forbidden - Insufficient permissions content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' examples: insufficientPermissions: summary: Insufficient permissions value: error: code: FORBIDDEN message: Insufficient permissions to perform this action InternalServerError: description: Internal Server Error - Unexpected error occurred content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' examples: internalError: summary: Unexpected server error value: error: code: INTERNAL_ERROR message: An unexpected error occurred. Please try again later. securitySchemes: ApiKeyAuth: type: apiKey in: header name: Authorization description: >- API key authentication. Include your API key in the Authorization header. ````