> ## Documentation Index > Fetch the complete documentation index at: https://docs.chatsailer.com/llms.txt > Use this file to discover all available pages before exploring further. # Add contacts to a campaign > **This causes real messages to be sent to real people.** The contacts you add here are messaged on the campaign's own schedule. Takes ids of contacts that already exist — create them first if they do not. Contacts already in the campaign are counted in `already_present` and are not enrolled twice. There is no way to request an immediate send. Enrolment and sending are separate decisions. ## OpenAPI ````yaml /api-reference/openapi.json post /v1/campaigns/{campaign_id}/participants openapi: 3.1.0 info: description: >- The Sailer REST API for CRM, conversations, and campaigns. **Authentication.** Send a scoped token as `Authorization: Bearer sk_live_...`. Tokens are workspace-scoped; the workspace is implied by the token, so no tenant header is needed. A workspace administrator creates and revokes them; the secret is shown once at creation and cannot be recovered afterwards. **Pagination.** Collections return `{data, meta, links}`. Follow `links.next` until it is `null`; treat the cursor as opaque. **Errors.** Every non-2xx response is `{"error": {...}}` with a stable `code`. Quote `error.request_id` when contacting support. **Custom fields.** Workspace-defined fields appear under `custom_fields`, keyed by `field_key`. Read a record to see which keys a workspace uses; a dedicated field-discovery endpoint is not part of this release. title: Sailer API version: 1.0.0 servers: - url: https://api.chatsailer.com security: - SailerApiToken: [] tags: - description: Token introspection and workspace capabilities. name: Meta - description: >- People you talk to. Called *leads* in older Sailer surfaces; `contact` is the current name. name: Contacts - description: Companies that contacts belong to (B2B accounts). name: Organizations - description: Opportunities moving through a pipeline. name: Deals - description: Pipelines and their stages. name: Pipelines - description: Field definitions, including custom fields. name: Fields - description: Free-text annotations on CRM records. name: Notes - description: Scheduled and logged CRM activities. name: Activities - description: Per-entity label catalogs. name: Tags - description: Message threads with contacts, across every channel. name: Conversations - description: Outbound campaigns and their participants. name: Campaigns paths: /v1/campaigns/{campaign_id}/participants: post: tags: - Campaigns summary: Add contacts to a campaign description: >- **This causes real messages to be sent to real people.** The contacts you add here are messaged on the campaign's own schedule. Takes ids of contacts that already exist — create them first if they do not. Contacts already in the campaign are counted in `already_present` and are not enrolled twice. There is no way to request an immediate send. Enrolment and sending are separate decisions. operationId: add_campaign_participants parameters: - in: path name: campaign_id required: true schema: description: Unique identifier for a campaign. examples: - camp_9f2ac41d8b7e4a51b0d3e6f7a1c2d3e4 pattern: ^camp_[0-9a-f]{32}$ title: Campaign Id type: string requestBody: content: application/json: schema: $ref: '#/components/schemas/EnrolContactsRequest' required: true responses: '201': content: application/json: schema: $ref: '#/components/schemas/EnrolmentResult' description: Successful Response '422': content: application/json: schema: $ref: '#/components/schemas/HTTPValidationError' description: Validation Error security: - SailerApiToken: [] components: schemas: EnrolContactsRequest: additionalProperties: false description: >- Body for adding contacts to a campaign or an audience. Takes ids of contacts that already exist, rather than contact details. This endpoint is not an import: creating people and messaging them should not be the same call, because the failure modes are different and only one of them is reversible. properties: contact_ids: description: Contacts to add. They must already exist in this workspace. items: description: Unique identifier for a contact. examples: - con_9f2ac41d8b7e4a51b0d3e6f7a1c2d3e4 pattern: ^con_[0-9a-f]{32}$ type: string maxItems: 1000 minItems: 1 title: Contact Ids type: array required: - contact_ids title: EnrolContactsRequest type: object EnrolmentResult: description: What an enrolment actually did. properties: added: description: Contacts newly enrolled. Excludes any already present. title: Added type: integer already_present: description: Contacts that were already in this campaign or audience. title: Already Present type: integer object: const: enrolment_result default: enrolment_result title: Object type: string required: - added - already_present title: EnrolmentResult type: object HTTPValidationError: properties: detail: items: $ref: '#/components/schemas/ValidationError' title: Detail type: array title: HTTPValidationError 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 securitySchemes: SailerApiToken: description: >- A workspace API token. Create one in Settings → API. Send it as `Authorization: Bearer sk_live_...`. scheme: bearer type: http ````