> ## Documentation Index
> Fetch the complete documentation index at: https://vastai-80aa3a82-auto-openapi-update-79df5d46.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Update Workergroup

> Updates scaling parameters, template, search params, or launch args on an existing workergroup; alias for PUT /api/v0/autojobs/{id}/.



## OpenAPI

````yaml /api-reference/openapi.yaml put /api/v0/workergroups/{id}/
openapi: 3.1.0
info:
  title: Vast.ai API
  description: >-
    Vast.ai REST API for managing GPU cloud instances, machine operations, and
    AI/ML workflows.


    ## AI Agent Quick-Start


    Install the CLI skill for your agent (Claude Code, Cursor, Windsurf, etc.):
      npx skills add vast-ai/vast-cli

    CLI reference:
    https://raw.githubusercontent.com/vast-ai/vast-cli/master/vastai/SKILL.md

    SDK reference:
    https://raw.githubusercontent.com/vast-ai/vast-cli/master/vastai_sdk/SKILL.md


    ## Auth

    All endpoints require `Authorization: Bearer $VAST_API_KEY`.

    Get your key at: https://cloud.vast.ai/manage-keys/


    ## Key Quirks

    - `gpu_ram` in CLI = GB; in REST API = MB (CLI auto-converts)

    - SSH keys must be registered BEFORE creating an instance (VM: no recovery;
    Docker: can add post-create)

    - `onstart` field is limited to 4048 characters -- gzip+base64 for longer
    scripts

    - `POST /api/v0/asks/{id}/` (create instance) returns `new_contract` as the
    instance ID, not `id`

    - Poll trap: if `actual_status` becomes `exited`, `unknown`, or `offline` it
    will never reach `running` -- destroy and retry
  version: 1.0.0
  contact:
    name: Vast.ai Support
    url: https://discord.gg/vast
servers:
  - url: https://console.vast.ai
    description: Production server
security:
  - BearerAuth: []
paths:
  /api/v0/workergroups/{id}/:
    put:
      tags:
        - Serverless
      summary: Update Workergroup
      description: >-
        Updates scaling parameters, template, search params, or launch args on
        an existing workergroup; alias for PUT /api/v0/autojobs/{id}/.
      parameters:
        - name: id
          in: path
          required: true
          schema:
            type: integer
          description: The ID of the workergroup to update.
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                min_load:
                  type: number
                  description: Minimum load for the workergroup.
                  example: 1
                target_util:
                  type: number
                  description: Target utilization for the workergroup.
                  example: 0.9
                cold_mult:
                  type: number
                  description: Cold multiplier for the workergroup.
                  example: 3
                test_workers:
                  type: integer
                  description: Number of test workers for performance estimation.
                  default: 3
                  example: 3
                template_hash:
                  type: string
                  description: Template hash for the workergroup.
                  example: abc123def456
                template_id:
                  type: integer
                  description: Template ID for the workergroup.
                  example: 456
                search_params:
                  type: string
                  description: Search parameters for offers (JSON object or query string).
                  default: verified=true rentable=true rented=false
                  example: gpu_name=RTX_3090 rentable=true
                launch_args:
                  type: string
                  description: Launch arguments for creating instances.
                  example: '--env VAR=value'
                gpu_ram:
                  type: number
                  description: Estimated GPU RAM requirement.
                  example: 24
                endpoint_name:
                  type: string
                  description: Deployment endpoint name.
                  example: vLLM-Qwen3-8B
                endpoint_id:
                  type: integer
                  description: Deployment endpoint ID.
                  example: 123
      responses:
        '200':
          description: 'Returns {success: true}'
          content:
            application/json:
              schema:
                type: object
                properties:
                  success:
                    type: boolean
                    description: Always true on success.
              example:
                success: true
        '400':
          description: >-
            Invalid arguments: missing endpoint_id, deployment-owned
            workergroup, endpoint not found, workergroup not found, or invalid
            search_params
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '403':
          description: Host-only accounts cannot update workergroups or use serverless
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
      security:
        - BearerAuth: []
components:
  schemas:
    Error:
      type: object
      properties:
        error:
          type: string
        msg:
          type: string
  securitySchemes:
    BearerAuth:
      type: http
      scheme: bearer
      description: API key must be provided in the Authorization header

````