> ## Documentation Index > Fetch the complete documentation index at: https://docs.stardex.com/llms.txt > Use this file to discover all available pages before exploring further. # Add campaign step > Add a step to the end of the campaign. People already enrolled keep the steps they were enrolled with and will not get this one, which the `existing_enrollees_will_not_receive_this_step` warning tells you. Needs `campaigns:write`. ## OpenAPI ````yaml /api-reference/openapi-v1.json post /v1/campaigns/{id}/steps openapi: 3.1.0 info: title: Stardex API (v1) version: 1.0.0 description: >- Stardex ATS API — manage candidates, jobs, companies, and recruiting workflows. servers: - url: https://api.stardex.ai description: Production API server security: - bearerAuth: [] tags: - name: Persons description: Manage person records — contacts, work history, and custom fields. - name: Jobs description: Manage job postings — pipeline stages, team members, and custom fields. - name: Candidates description: Manage candidate records and pipeline stage transitions. - name: Companies description: Browse and retrieve company records. - name: Lists description: Create, search, and retrieve saved person and company lists. - name: Person Activities description: Create and manage activity records (notes, emails, meetings) for persons. - name: Team Members description: List team members for use in search filters and assignments. - name: Custom Fields description: Retrieve custom field definitions and tag options for search filters. - name: Campaigns description: >- Create and edit email campaigns, enroll people through enrollment batches, and manage who is enrolled. paths: /v1/campaigns/{id}/steps: post: tags: - Campaigns summary: Add campaign step description: >- Add a step to the end of the campaign. People already enrolled keep the steps they were enrolled with and will not get this one, which the `existing_enrollees_will_not_receive_this_step` warning tells you. Needs `campaigns:write`. operationId: addCampaignStep parameters: - schema: type: string format: uuid description: Campaign ID. required: true description: Campaign ID. name: id in: path requestBody: content: application/json: schema: $ref: '#/components/schemas/CampaignStepInput' example: type: email send_after_days: 4 body_html: >-
Hi {{first_name}}, closing the loop on this. Happy to share more whenever suits.

{{sender_first_name}}
time_window_start: '09:00' time_window_end: '17:00' include_signature: true responses: '201': description: Step added content: application/json: schema: $ref: '#/components/schemas/CampaignStepResponse' example: success: true data: step: id: 2b7d9f1a-5c3e-4a8b-9d6f-0e2c4a6b8d31 order: 4 type: email send_after_days: 4 subject: 'Re: {{search_name}} role at {{search_client}}' body_html: >-
Hi {{first_name}}, closing the loop on this. Happy to share more whenever suits.

{{sender_first_name}}
timezone: Europe/London time_window_start: '09:00' time_window_end: '17:00' include_signature: true block_until_task_complete: false ai_variables: [] attachments: [] created_at: '2026-10-14T09:02:00.000Z' updated_at: '2026-10-14T09:02:00.000Z' warnings: - code: existing_enrollees_will_not_receive_this_step message: >- People already in this campaign keep their current steps and will not get this one. Only people enrolled from now on will. '400': description: Validation error content: application/json: schema: type: object properties: success: type: boolean enum: - false description: Always false for error responses. error: type: object properties: code: type: string description: >- Machine-readable error code (e.g. "VALIDATION_ERROR", "NOT_FOUND"). message: type: string description: Human-readable error description. details: type: object additionalProperties: {} description: >- Extra facts about the error when they help you fix it, such as a limit and when it resets. required: - code - message required: - success - error '403': description: No access to campaigns, or the API key lacks the permission content: application/json: schema: type: object properties: success: type: boolean enum: - false description: Always false for error responses. error: type: object properties: code: type: string description: >- Machine-readable error code (e.g. "VALIDATION_ERROR", "NOT_FOUND"). message: type: string description: Human-readable error description. details: type: object additionalProperties: {} description: >- Extra facts about the error when they help you fix it, such as a limit and when it resets. required: - code - message required: - success - error '404': description: Resource not found content: application/json: schema: type: object properties: success: type: boolean enum: - false description: Always false for error responses. error: type: object properties: code: type: string description: >- Machine-readable error code (e.g. "VALIDATION_ERROR", "NOT_FOUND"). message: type: string description: Human-readable error description. details: type: object additionalProperties: {} description: >- Extra facts about the error when they help you fix it, such as a limit and when it resets. required: - code - message required: - success - error '500': description: Internal server error content: application/json: schema: type: object properties: success: type: boolean enum: - false description: Always false for error responses. error: type: object properties: code: type: string description: >- Machine-readable error code (e.g. "VALIDATION_ERROR", "NOT_FOUND"). message: type: string description: Human-readable error description. details: type: object additionalProperties: {} description: >- Extra facts about the error when they help you fix it, such as a limit and when it resets. required: - code - message required: - success - error components: schemas: CampaignStepInput: type: object properties: type: type: string enum: - email - manual - text - linkedin_message - linkedin_connection - call description: >- Step type. Email steps are sent automatically; the others create tasks. send_after_days: type: integer minimum: 0 maximum: 365 description: >- Days to wait after the previous step (or after enrollment, for the first step). subject: type: - string - 'null' maxLength: 998 description: >- Email subject, or the InMail subject for LinkedIn message steps. Only the first email step has its own subject: later email steps always use "Re: " so they land in the same thread (a "Re:" on the first email is removed). Editing a later email's subject is rejected. Can use {{variables}}. body_html: type: string maxLength: 100000 description: >- Step body as HTML (paragraphs, headings, line breaks, bold, italic, underline, strikethrough, highlight, links, lists and images). Each

is followed by an empty line, as in the campaign builder; use
for a line break without a gap. Images need a public https URL and are shown as their own block. Can use {{variables}}, including inside link URLs. For non-email steps this is the task or message text; LinkedIn connection notes are limited to 300 characters. timezone: type: - string - 'null' description: >- IANA timezone for the sending window, for example Europe/London. Defaults to the timezone of the campaign owner's first connected mailbox. Without one, the step sends in New York business hours (America/New_York). time_window_start: type: - string - 'null' pattern: ^([01]\d|2[0-3]):[0-5]\d$ description: >- Start of the sending window for email steps, in 24-hour HH:MM. Left empty, the step sends between 09:00 and 17:00 in its timezone. time_window_end: type: - string - 'null' pattern: ^([01]\d|2[0-3]):[0-5]\d$ description: >- End of the sending window for email steps, in 24-hour HH:MM. Must differ from time_window_start. include_signature: type: boolean description: Add the sender's email signature to this email step. block_until_task_complete: type: boolean description: >- For task steps (not emails): hold the rest of the campaign until this task is marked complete. Turning it off releases anyone already waiting on the step. ai_variables: type: array items: type: object properties: name: type: string minLength: 1 maxLength: 64 description: >- The name used in the template, without the ai: prefix. {{ai:opening_line}} has the name opening_line. description: type: string minLength: 1 maxLength: 1000 description: >- What the AI should write for each person, for example "One sentence on their most relevant recent work". The value is inserted exactly as written, so use the variable only where that text fits: a sentence on its own, never mid-sentence. required: - name - description maxItems: 20 description: >- A description for every {{ai:name}} used in this step. Descriptions for names not used in the step are ignored. required: - type - send_after_days CampaignStepResponse: type: object properties: success: type: boolean enum: - true data: type: object properties: step: $ref: '#/components/schemas/CampaignStep' warnings: type: array items: type: object properties: code: type: string description: Machine-readable warning code. message: type: string description: What it means for you. required: - code - message required: - step - warnings required: - success - data CampaignStep: type: object properties: id: type: string format: uuid order: type: integer description: 1-based position in the campaign. type: type: string enum: - email - manual - text - linkedin_message - linkedin_connection - call send_after_days: type: integer subject: type: - string - 'null' body_html: type: string timezone: type: - string - 'null' time_window_start: type: - string - 'null' description: >- HH:MM. null means the default sending hours, 09:00–17:00 in the step's timezone. time_window_end: type: - string - 'null' description: >- HH:MM. null means the default sending hours, 09:00–17:00 in the step's timezone. include_signature: type: boolean block_until_task_complete: type: boolean ai_variables: type: array items: type: object properties: name: type: string minLength: 1 maxLength: 64 description: >- The name used in the template, without the ai: prefix. {{ai:opening_line}} has the name opening_line. description: type: string minLength: 1 maxLength: 1000 description: >- What the AI should write for each person, for example "One sentence on their most relevant recent work". The value is inserted exactly as written, so use the variable only where that text fits: a sentence on its own, never mid-sentence. required: - name - description attachments: type: array items: type: object properties: file_name: type: string content_type: type: - string - 'null' size_bytes: type: integer required: - file_name - content_type - size_bytes description: >- Files sent with this step, added in the campaign builder. Attachments cannot be added through the API. created_at: type: string updated_at: type: - string - 'null' required: - id - order - type - send_after_days - subject - body_html - timezone - time_window_start - time_window_end - include_signature - block_until_task_complete - ai_variables - attachments - created_at - updated_at securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: JWT description: >- Authenticate with a Bearer token: API key, OAuth token, or session token. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.