> ## Documentation Index > Fetch the complete documentation index at: https://developers.criteo.com/llms.txt > Use this file to discover all available pages before exploring further. # /2025-01/marketing-solutions/audience-segments/{audience-segment-id}/contact-list > Add/remove identifiers to or from a contact list audience-segment. ## OpenAPI ````yaml https://api.criteo.com/2025-01/marketingsolutions/open-api-specifications.json patch /2025-01/marketing-solutions/audience-segments/{audience-segment-id}/contact-list openapi: 3.0.1 info: title: Criteo API description: Criteo API - MarketingSolutions version: 2025-01 servers: - url: https://api.criteo.com security: - oauth: [] tags: - name: Advertiser - name: Analytics - name: Audience - name: Campaign - name: Creative - name: Gateway paths: /2025-01/marketing-solutions/audience-segments/{audience-segment-id}/contact-list: parameters: - name: audience-segment-id in: path description: The id of the contact list audience-segment to amend required: true schema: type: string format: int32 patch: tags: - Audience summary: >- /2025-01/marketing-solutions/audience-segments/{audience-segment-id}/contact-list description: Add/remove identifiers to or from a contact list audience-segment. operationId: UpdateContactListByAudienceSegment requestBody: content: application/json: schema: $ref: '#/components/schemas/ContactlistAmendmentRequest' required: true x-bodyName: body responses: '200': description: Summary of created request content: application/json: schema: $ref: '#/components/schemas/ModifyAudienceResponse' example: data: type: ContactlistAmendment attributes: contactListId: 12 operation: add requestDate: '2018-12-10T10:00:50.0000000+00:00' identifierType: madid nbValidIdentifiers: 7343 nbInvalidIdentifiers: 13 sampleInvalidIdentifiers: - InvalidIdentifier errors: [] warnings: - traceId: 56ed4096-f96a-4944-8881-05468efe0ec9 type: deprecation code: deprecated-field instance: /audiences/314195 title: '''nbValidIds'' is deprecated' detail: >- The field 'nbValidIds' is deprecated please use 'nbValidIdentifiers security: - oauth: - MarketingSolutions_Audience_Manage components: schemas: ContactlistAmendmentRequest: required: - data type: object properties: data: $ref: '#/components/schemas/ContactlistAmendment' description: Request for a contactlist amendment ModifyAudienceResponse: required: - data - errors - warnings type: object properties: data: $ref: '#/components/schemas/ContactlistOperation' errors: type: array items: $ref: '#/components/schemas/AudienceError' warnings: type: array items: $ref: '#/components/schemas/AudienceWarning' description: Parameters to modify an audience ContactlistAmendment: required: - attributes - type type: object properties: attributes: required: - identifiers - operation type: object properties: gumCallerId: type: integer description: >- The Gum caller id of the advertiser patching identifiers of type Gum identifiers: type: array items: type: string description: The users to add or remove, each in the schema specified identifierType: enum: - email - madid - identityLink - gum - phoneNumber type: string description: What type of identifiers are used operation: enum: - add - remove type: string description: Operation to add or remove users description: the name of the entity type type: type: string description: User List example: ContactlistAmendment description: Parameters for the amendment of a contactlist ContactlistOperation: required: - attributes - type type: object properties: attributes: required: - operation type: object properties: contactListId: type: integer description: the affected user list id nullable: true identifierType: type: string description: The schema specified for of the identifiers nullable: true nbInvalidIdentifiers: type: integer description: How many identifiers were invalid for the specified schema nullable: true nbValidIdentifiers: type: integer description: How many identifiers were valid for the specified schema nullable: true operation: type: string description: The action recorded requestDate: type: string description: When the action was recorded format: date-time nullable: true sampleInvalidIdentifiers: type: array items: type: string description: A sample of invalid identifiers if there is some nullable: true description: the contactlist operation attributes type: type: string description: the name of the entity type description: Response definition of a contactlist operation AudienceError: required: - code - instance - type type: object properties: code: type: string description: >- (REQUIRED) A machine-readable unique error code, expressed as a string value. The format used must be kebab-case. detail: type: string description: >- (RECOMMENDED) A human-readable explanation specific to this occurrence of the problem nullable: true instance: type: string description: >- (REQUIRED) A URI reference that identifies the specific occurrence of the problem source: type: object description: >- (OPTIONAL) A machine-readable structure to reference to the exact location(s) causing the error(s) nullable: true stackTrace: type: array items: type: string description: >- (NEVER IN PRODUCTION) A human-readable stacktrace produced by the implementation technology nullable: true title: type: string description: (RECOMMENDED) A short, human-readable summary of the problem type nullable: true traceId: type: string description: >- (REQUIRED) The Correlation ID provided by the Gateway. It is also a unique identifier for this particular occurrence of the problem. nullable: true type: enum: - access-control - authentication - authorization - availability - deprecation - quota - validation type: string description: (REQUIRED) The classification of the error description: Definition of an audience error AudienceWarning: required: - code - detail - instance - type type: object properties: code: type: string description: >- (REQUIRED) A machine-readable unique error code, expressed as a string value. The format used must be kebab-case. detail: type: string description: >- (REQUIRED) A human-readable explanation specific to this occurrence of the problem instance: type: string description: >- (REQUIRED) A URI reference that identifies the specific occurrence of the problem source: type: object description: >- (OPTIONAL) A machine-readable structure to reference to the exact location(s) causing the error(s) nullable: true stackTrace: type: array items: type: string description: >- (NEVER IN PRODUCTION) A human-readable stacktrace produced by the implementation technology nullable: true title: type: string description: (RECOMMENDED) A short, human-readable summary of the problem type nullable: true traceId: type: string description: >- (REQUIRED) The Correlation ID provided by the Gateway. It is also a unique identifier for this particular occurrence of the problem. nullable: true type: enum: - access-control - authentication - authorization - availability - deprecation - quota - validation type: string description: (REQUIRED) The classification of the error description: Definition of the warning securitySchemes: oauth: type: oauth2 flows: clientCredentials: tokenUrl: https://api.criteo.com/oauth2/token scopes: {} authorizationCode: authorizationUrl: https://api.criteo.com/oauth2 tokenUrl: https://api.criteo.com/oauth2/token scopes: {} ````