> ## Documentation Index
> Fetch the complete documentation index at: https://docs.outreign.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Create an activity



## OpenAPI

````yaml /public/openapi.json post /activities
openapi: 3.1.0
info:
  title: OutReign API
  version: 1.0.0
  summary: B2B lead intelligence and outbound sales API
  description: >-
    REST API for OutReign saved leads, deals, activities, contacts and AI email
    generation. Authenticate with X-API-Key from Settings → API Keys. MCP OAuth
    and webhook contracts are documented separately at https://docs.outreign.io.
  contact:
    name: OutReign support
    email: support@bdotindustries.com
    url: https://outreign.io/connect
  termsOfService: https://outreign.io/terms
servers:
  - url: https://api.outreign.io/rest-api
    description: Production
security:
  - ApiKeyAuth: []
tags:
  - name: Leads
  - name: Deals
  - name: Activities
  - name: Contacts
  - name: Outreach
externalDocs:
  description: Human API documentation
  url: https://docs.outreign.io
paths:
  /activities:
    post:
      tags:
        - Activities
      summary: Create an activity
      operationId: createActivity
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ActivityInput'
      responses:
        '201':
          description: Created
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    $ref: '#/components/schemas/Activity'
        '401':
          description: Missing, invalid, inactive or expired API key
        '403':
          description: Account plan or access restriction
        '429':
          description: Rate limit exceeded; inspect resetAt and rate-limit headers
components:
  schemas:
    ActivityInput:
      type: object
      properties:
        subject:
          type: string
        type:
          type: string
        description:
          type: string
        completed:
          type: boolean
        due_date:
          type: string
          format: date-time
        deal_id:
          type: string
          format: uuid
        lead_id:
          type: string
          format: uuid
      additionalProperties: false
      required:
        - subject
        - type
    Activity:
      type: object
      properties:
        id:
          type: string
          format: uuid
          readOnly: true
        subject:
          type: string
        type:
          type: string
        due_date:
          type: string
          format: date-time
        completed:
          type: boolean
        lead_id:
          type: string
          format: uuid
        description:
          type: string
        deal_id:
          type: string
          format: uuid
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: X-API-Key
      description: Create keys in OutReign → Settings → API Keys.

````

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