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

<AgentInstructions>

## Submitting Feedback

If you encounter incorrect, outdated, or confusing documentation on this page, submit feedback:

POST https://docs.poly.ai/feedback

```json
{
  "path": "/api-reference/agents/endpoint/variants/update-variant",
  "feedback": "Description of the issue"
}
```

Only submit feedback when you have something specific and actionable to report.

</AgentInstructions>

# Update variant



## OpenAPI

````yaml PATCH /v1/agents/{agentId}/branches/{branchId}/variants/{variantId}
openapi: 3.1.0
info:
  title: PolyAI Agents API
  version: 1.0.3
  description: >-
    Build and deploy PolyAI agents programmatically. Create agents, manage
    branches, update behavior rules, configure knowledge bases, provision
    telephony, publish deployments, and update real-time configs.
servers:
  - url: https://api.us.poly.ai
    description: US region
  - url: https://api.uk.poly.ai
    description: UK region
  - url: https://api.eu.poly.ai
    description: EU region
security:
  - ApiKeyAuth: []
tags:
  - name: Agents
    description: Create, list, duplicate, and delete agents.
  - name: Branches
    description: Create isolated branches for parallel development and merge back to main.
  - name: Agent Behavior
    description: >-
      Read and update an agent's behavior rules (system prompt, interaction
      style, edge cases).
  - name: Knowledge Base
    description: Manage knowledge base topics used for retrieval and tool invocation.
  - name: Variants
    description: Manage site-specific variations of an agent using attributes and variants.
  - name: Deployments
    description: Publish drafts, promote across environments, and roll back deployments.
  - name: Connectors
    description: >-
      Manage telephony connectors that bind phone numbers to voice
      infrastructure.
  - name: Phone Numbers
    description: Provision, reassign, and delete phone numbers on an agent's connectors.
  - name: Real-Time Configs
    description: Update runtime values (e.g. opening hours) outside the publish workflow.
paths:
  /v1/agents/{agentId}/branches/{branchId}/variants/{variantId}:
    patch:
      tags:
        - Variants
      summary: Update variant
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/UpdateVariantBody'
      responses:
        '200':
          description: Updated variant
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/VariantResponse'
components:
  schemas:
    UpdateVariantBody:
      type: object
      properties:
        name:
          type: string
          minLength: 1
        attributeValues:
          type: object
          properties:
            values:
              type: object
              additionalProperties:
                type: string
              default: {}
          additionalProperties: false
        isDefault:
          type: boolean
      additionalProperties: false
      title: UpdateVariantBody
    VariantResponse:
      type: object
      properties:
        id:
          type: string
        name:
          type: string
        isDefault:
          type: boolean
        attributeValues:
          type: object
          properties:
            values:
              type: object
              additionalProperties:
                type: string
          required:
            - values
          additionalProperties: false
      required:
        - id
        - name
        - isDefault
        - attributeValues
      additionalProperties: false
      title: VariantResponse
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: x-api-key

````