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

# Set run tag

> Set a tag on a run. Tags are run metadata that can be updated during a run and after a run completes.



## OpenAPI

````yaml /api-specs/cloud/public-api.json post /api/2.0/mlflow/runs/set-tag
openapi: 3.0.3
info:
  title: Domino Public API
  description: Reference for Domino's public REST API endpoints.
  version: 6.4.0
  x-catalog-key: nucleus
servers:
  - url: https://mycluster.domino.tech
    description: >-
      Replace 'mycluster.domino.tech' with your Domino cluster hostname. For
      Domino Cloud customers, that is `your-subdomain`.domino.tech (e.g.,
      acme.domino.tech). For self-hosted deployments, it is the hostname you
      reach the Domino UI at.
security: []
tags:
  - name: Projects
  - name: Project templates
  - name: Workspaces
  - name: Jobs
  - name: HPC Jobs
  - name: Environments
  - name: Hardware Tiers
  - name: Datasets
  - name: Data Sources
  - name: GenAI
  - name: AI Systems
  - name: MLflow experiments and runs
  - name: MLflow models
  - name: MLflow artifacts
  - name: MLflow traces
  - name: Apps
  - name: App versions
  - name: App instances
  - name: Model APIs
  - name: Registered models
  - name: Model deployment
  - name: Extensions
  - name: Cost and billing
  - name: Users and organizations
  - name: Service accounts
  - name: Personal Access Tokens
  - name: Personal Access Tokens (admin)
  - name: Audit Trail
  - name: Custom metrics
  - name: PPM
  - name: Model Monitoring models
  - name: Model Monitoring drift and quality
  - name: Model Monitoring settings
  - name: Model Monitoring authentication
  - name: Governance bundles
  - name: Governance policies
  - name: Governance evidence and results
  - name: Governance operations
  - name: NetApp Volumes
  - name: NetApp Volumes snapshots
  - name: NetApp Volumes filesystems
  - name: NetApp Volumes transfers
  - name: Tags
  - name: Properties
externalDocs:
  description: OpenAPI
  url: https://swagger.io/resources/open-api/
paths:
  /api/2.0/mlflow/runs/set-tag:
    post:
      tags:
        - MLflow experiments and runs
      description: >-
        Set a tag on a run. Tags are run metadata that can be updated during a
        run and after a run completes.
      operationId: runs.SetTag
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/mlflow-proxy_SetRunTagRequest'
      responses:
        '200':
          description: Run tag set successfully
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/mlflow-proxy_SetRunTagResponse'
        default:
          $ref: '#/components/responses/mlflow-proxy_MLflowNativeError'
components:
  schemas:
    mlflow-proxy_SetRunTagRequest:
      allOf:
        - $ref: '#/components/schemas/mlflow-proxy_Tag'
        - type: object
          properties:
            run_id:
              description: ID of the run under which to log the tag. Must be provided.
              type: string
          required:
            - run_id
    mlflow-proxy_SetRunTagResponse:
      properties: {}
      type: object
    mlflow-proxy_Tag:
      properties:
        key:
          description: >-
            Name of the tag. Maximum size depends on storage backend.

            If a tag with this name already exists, its preexisting value will
            be replaced by the specified value. All storage backends are
            guaranteed to support key values up to 250 bytes in size. This field
            is required.
          type: string
        value:
          description: >-
            String value of the tag being logged. Maximum size depends on
            storage backend.

            All storage backends are guaranteed to support key values up to 5000
            bytes in size. This field is required.
          type: string
      required:
        - key
        - value
      type: object
    mlflow-proxy_ErrorResponse:
      properties:
        error_code:
          $ref: '#/components/schemas/mlflow-proxy_ErrorCode'
        message:
          description: Error message
          type: string
      required:
        - error_code
        - message
      type: object
    mlflow-proxy_ErrorCode:
      description: Error code
      enum:
        - INTERNAL_ERROR
        - INVALID_STATE
        - DATA_LOSS
        - NOT_IMPLEMENTED
        - TEMPORARILY_UNAVAILABLE
        - DEADLINE_EXCEEDED
        - CANCELLED
        - RESOURCE_EXHAUSTED
        - REQUEST_LIMIT_EXCEEDED
        - ABORTED
        - RESOURCE_CONFLICT
        - ALREADY_EXISTS
        - NOT_FOUND
        - ENDPOINT_NOT_FOUND
        - RESOURCE_DOES_NOT_EXIST
        - PERMISSION_DENIED
        - CUSTOMER_UNAUTHORIZED
        - UNAUTHENTICATED
        - BAD_REQUEST
        - RESOURCE_ALREADY_EXISTS
        - INVALID_PARAMETER_VALUE
      type: string
  responses:
    mlflow-proxy_MLflowNativeError:
      description: The client issued a bad request to the server
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/mlflow-proxy_ErrorResponse'

````

## Related topics

- [Knowledge management](/cloud/platform-capabilities/core-concepts/knowledge-management/index.md)
- [Tags](/cloud/platform-capabilities/core-concepts/knowledge-management/tags.md)
- [Set experiment tag](/api-reference/mlflow-experiments-and-runs/post-api20mlflowexperimentsset-experiment-tag.md)
- [Set Logged Model Tag](/api-reference/mlflow-models/set-logged-model-tag.md)