> ## Documentation Index > Fetch the complete documentation index at: https://docs.member.dev/llms.txt > Use this file to discover all available pages before exploring further. # Create Conversation > Create a new DM conversation (1:1 or group). For 1:1: idempotent — returns the existing conversation if one already exists between the two contacts in this hub. Requires the caller and all audience contacts to be active hub members. Returns 422 when fewer than 2 distinct contacts are provided or when the group cap (50 members) would be exceeded. Requires Content-Type: application/vnd.api+json. ## OpenAPI ````yaml /openapi/mio-openapi.json post /api/v1/hubs/{hub_id}/conversations openapi: 3.1.0 info: description: >- Production API reference for Membership.io. Use the authored guides for workflows and the generated endpoint pages for exact parameters and schemas. title: Membership.io API version: 0.1.0 servers: - description: Production url: https://api.member.dev security: - bearerAuth: [] paths: /api/v1/hubs/{hub_id}/conversations: post: tags: - community-conversations summary: Create Conversation description: |- Create a new DM conversation (1:1 or group). For 1:1: idempotent — returns the existing conversation if one already exists between the two contacts in this hub. Requires the caller and all audience contacts to be active hub members. Returns 422 when fewer than 2 distinct contacts are provided or when the group cap (50 members) would be exceeded. Requires Content-Type: application/vnd.api+json. operationId: >- community_conversations.post_community_conversations_post_hubs_by_hub_id_conversations parameters: - in: path name: hub_id required: true schema: title: Hub Id type: string requestBody: content: application/vnd.api+json: schema: $ref: '#/components/schemas/ConversationCreateEnvelope' required: true responses: '201': content: application/vnd.api+json: schema: $ref: >- #/components/schemas/JsonApiResponse_ConversationResponseAttributes_ description: Successful Response '422': content: application/vnd.api+json: schema: $ref: '#/components/schemas/HTTPValidationError' description: Validation Error security: - HTTPBearer: [] components: schemas: ConversationCreateEnvelope: properties: data: $ref: '#/components/schemas/_ConversationCreateData' required: - data title: ConversationCreateEnvelope type: object JsonApiResponse_ConversationResponseAttributes_: properties: data: $ref: '#/components/schemas/JsonApiResource_ConversationResponseAttributes_' included: anyOf: - items: {} type: array - type: 'null' title: Included links: anyOf: - $ref: '#/components/schemas/JsonApiLinks' - type: 'null' meta: anyOf: - additionalProperties: true type: object - type: 'null' title: Meta required: - data title: JsonApiResponse[ConversationResponseAttributes] type: object HTTPValidationError: properties: detail: items: $ref: '#/components/schemas/ValidationError' title: Detail type: array title: HTTPValidationError type: object _ConversationCreateData: properties: attributes: $ref: '#/components/schemas/_ConversationCreateAttributes' type: title: Type type: string required: - type - attributes title: _ConversationCreateData type: object JsonApiResource_ConversationResponseAttributes_: properties: attributes: $ref: '#/components/schemas/ConversationResponseAttributes' id: title: Id type: string links: anyOf: - $ref: '#/components/schemas/JsonApiLinks' - type: 'null' meta: anyOf: - additionalProperties: true type: object - type: 'null' title: Meta relationships: anyOf: - additionalProperties: true type: object - type: 'null' title: Relationships type: title: Type type: string required: - id - type - attributes title: JsonApiResource[ConversationResponseAttributes] type: object JsonApiLinks: properties: self: anyOf: - type: string - type: 'null' title: Self title: JsonApiLinks type: object ValidationError: properties: ctx: title: Context type: object input: title: Input loc: items: anyOf: - type: string - type: integer title: Location type: array msg: title: Message type: string type: title: Error Type type: string required: - loc - msg - type title: ValidationError type: object _ConversationCreateAttributes: properties: audience_contact_ids: items: type: string title: Audience Contact Ids type: array title: anyOf: - type: string - type: 'null' title: Title required: - audience_contact_ids title: _ConversationCreateAttributes type: object ConversationResponseAttributes: properties: created_at: anyOf: - type: string - type: 'null' title: Created At hub_id: anyOf: - type: string - type: 'null' title: Hub Id is_archived: anyOf: - type: boolean - type: 'null' title: Is Archived is_group: anyOf: - type: boolean - type: 'null' title: Is Group is_muted: anyOf: - type: boolean - type: 'null' title: Is Muted is_pinned: anyOf: - type: boolean - type: 'null' title: Is Pinned last_entry: anyOf: - $ref: '#/components/schemas/LastEntryPreview' - type: 'null' last_message_at: anyOf: - type: string - type: 'null' title: Last Message At last_message_preview: anyOf: - type: string - type: 'null' title: Last Message Preview participants: default: [] items: $ref: '#/components/schemas/ParticipantSummary' title: Participants type: array title: anyOf: - type: string - type: 'null' title: Title unread_count: anyOf: - type: integer - type: 'null' title: Unread Count title: ConversationResponseAttributes type: object LastEntryPreview: properties: author_contact_id: anyOf: - type: string - type: 'null' title: Author Contact Id author_display_name: anyOf: - type: string - type: 'null' title: Author Display Name body_preview: anyOf: - type: string - type: 'null' title: Body Preview created_at: anyOf: - type: string - type: 'null' title: Created At entry_kind: $ref: '#/components/schemas/MessageEntryKind' event: anyOf: - $ref: '#/components/schemas/MessageEventData' - type: 'null' required: - entry_kind title: LastEntryPreview type: object ParticipantSummary: description: >- A DM conversation participant summary for embedding in ConversationResponseAttributes. Not a JSON:API resource — no type/id fields. Embedded directly in the conversation attributes.participants list. properties: contact_id: title: Contact Id type: string display_name: anyOf: - type: string - type: 'null' title: Display Name last_seen_at: anyOf: - type: string - type: 'null' title: Last Seen At photo_url: anyOf: - type: string - type: 'null' title: Photo Url photo_url_expires_at: anyOf: - format: date-time type: string - type: 'null' title: Photo Url Expires At role: title: Role type: string required: - contact_id - display_name - photo_url - last_seen_at - role title: ParticipantSummary type: object MessageEntryKind: enum: - text - conversation_title_changed title: MessageEntryKind type: string MessageEventData: properties: previous_title: anyOf: - type: string - type: 'null' title: Previous Title title: anyOf: - type: string - type: 'null' title: Title required: - previous_title - title title: MessageEventData type: object securitySchemes: bearerAuth: bearerFormat: JWT or mio_sk API key description: >- Send platform JWTs, contact JWTs, or team API keys as `Authorization: Bearer `. scheme: bearer type: http HTTPBearer: scheme: bearer type: http ````