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

# Update Contacts (Batch)

> Updates multiple contacts in a single request. Limited to 1000 contacts per request. Only provided fields will be updated, others remain unchanged.

<Warning>
  This endpoint is deprecated. A V2 replacement is not yet available. See the [Migration Guide](/v2-migration-guide) for details.
</Warning>


## OpenAPI

````yaml openapi.json PATCH /v1/update-contacts-batch
openapi: 3.0.3
info:
  title: telli API
  version: 1.0.0
  description: API documentation for telli's V1 endpoints
servers:
  - url: https://api.telli.com
security:
  - apiKey: []
paths:
  /v1/update-contacts-batch:
    patch:
      summary: Update Contacts Batch
      description: >-
        Updates multiple contacts in a single request. Limited to 1000 contacts
        per request. Only provided fields will be updated, others remain
        unchanged.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - contacts
              properties:
                contacts:
                  type: array
                  items:
                    type: object
                    required:
                      - contact_id
                    properties:
                      contact_id:
                        type: string
                        format: uuid
                        description: >-
                          The telli contact ID received when creating the
                          contact
                      first_name:
                        type: string
                        description: First name of the contact
                      last_name:
                        type: string
                        description: Last name of the contact
                      phone_number:
                        type: string
                        description: >-
                          Contact's phone number in E.164 format (e.g.
                          +4917642048466)
                      contact_details:
                        type: object
                        description: >-
                          Custom variables passed to the AI agent. The entire
                          object will be overwritten. This used to be called
                          dynamic_variables, which still works but is deprecated
                          and should be replaced with contact_details.
                      salutation:
                        type: string
                        description: >-
                          Formal title or greeting (e.g. 'Mr.', 'Ms.', 'Herr',
                          'Frau')
                      email:
                        type: string
                        format: email
                        description: Contact's email address
                      timezone:
                        type: string
                        description: IANA timezone identifier (e.g. Europe/Berlin)
                      external_contact_id:
                        type: string
                        description: Your unique internal identifier for the contact
                      external_url:
                        type: string
                        format: uri
                        description: >-
                          External URL linking to the contact in your CRM or
                          external system
                  description: >-
                    Array of contacts to update. Maximum 1000 contacts per
                    request.
      responses:
        '200':
          description: Contacts updated successfully
          content:
            application/json:
              schema:
                type: array
                items:
                  type: object
                  properties:
                    contact_id:
                      type: string
                      format: uuid
                      description: The telli contact ID
                    status:
                      type: string
                      enum:
                        - success
                        - error
                      description: Status of the contact update
                    error:
                      type: string
                      description: Error message (only present for failed updates)
        '400':
          description: Invalid request
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '401':
          description: Unauthorized - Invalid API key
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
components:
  schemas:
    Error:
      type: object
      properties:
        message:
          type: string
  securitySchemes:
    apiKey:
      type: apiKey
      in: header
      name: Authorization
      description: 'API key must be provided as: Bearer <api_key>'
      x-bearer-format: Bearer

````