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

# Add an eval column

> Links an existing evaluator. Each row gets one evaluator cell per task column. Config is updated at the evaluator source, not here.

> [!NOTE]
>
> **Related guide**: Experiments guide. See the [Experiments guide](https://docs.orq.ai/ai-studio/optimize/experiments.md) for a walkthrough with examples.


## OpenAPI

````yaml post /v3/experiments/{experiment_id}/runs/{run_id}/evaluators
openapi: 3.1.0
info:
  title: orq.ai API
  version: '2.0'
  description: orq.ai API documentation
servers:
  - url: https://my.orq.ai
security:
  - ApiKey: []
tags:
  - name: Chunking
    description: Split text into smaller chunks for retrieval and generation workflows.
  - name: File Systems
    description: >-
      Create and manage persistent file systems that agents and MCP clients read
      from and write to.
  - name: Knowledge Bases
    description: Create and manage knowledge bases used by agents and retrieval workflows.
  - name: Memory Stores
    description: Create and manage memory stores, memories, and memory documents.
  - name: Evals
    description: Run an evaluator against a conversation and its result
  - name: Logs
    description: >-
      OpenTelemetry log query API. Search, filter, aggregate, and facet log
      records ingested via OTLP.
  - name: Reporting
    description: >-
      GenAI reporting API over canonical analytics rollups. Accepts a metric
      name, time range, grain, group-by, and filters; returns a typed time
      series and optional totals.
  - name: Traces
    description: >-
      Query and inspect ingested trace data: search trace summaries, aggregate
      metrics, and read individual traces and their spans.
  - name: Experiments
    description: >-
      Create and run experiments: dataset rows against task columns, evaluators,
      and human review.
  - description: List models available through the AI Router.
    name: Models
  - name: Alerts
    description: >-
      Alerts evaluate a Reporting API metric on a fixed interval and fire
      notifications through notifiers when the value breaches a threshold. Each
      breach opens a trigger that tracks the incident until the value recovers.
  - name: Annotation Queues
    description: Annotation queues collect spans for human review.
  - name: API keys
    description: >-
      API keys authenticate programmatic access to the workspace. They expose
      opaque tokens, per-domain access grants, and budget and rate-limit
      constraints.
  - name: Audit Logs
    description: Audit logs record workspace entity changes and access-relevant events.
  - name: Budgets
    description: >-
      Budgets govern spend, token usage, and request rate across six scopes:
      workspace, project, identity, API key, provider, and model. Every
      applicable budget is enforced, and the most restrictive limit applies per
      dimension.
  - name: Files
    description: File upload and retrieval operations.
  - name: Guardrail Rules
    description: >-
      Guardrail Rules conditionally enforce evaluators and plugins for AI
      Gateway traffic. Rules may be scoped to a project or the whole workspace.
  - name: Hub
    description: Hub items are reusable templates available to a workspace.
  - name: Identities
    description: >-
      Identities represent end users from your system for usage and engagement
      tracking.
  - name: Management keys
    description: >-
      Management keys are workspace-scoped credentials that authenticate
      programmatic access to workspace administration surfaces (API keys,
      budgets). Unlike project-scoped API keys, a management key always operates
      at the workspace level.
  - name: MCP Gateway
    description: >-
      Register upstream MCP servers, discover and sync their tools, and assemble
      gateways that expose a curated tool surface to MCP clients.
  - name: Model Catalog
    description: >-
      Browse the orq.ai model catalog: every model orq offers, across every
      provider, with pricing, capabilities and benchmark data. List endpoints
      only return models that are not deprecated. This API is public, requires
      no authentication, and is rate limited to 120 requests per minute per IP.
      Responses carry a 5-minute cache-control max-age.
  - name: Model Fusions
    description: >-
      Model Fusions combine independent model answers through a panel, judge,
      and optional synthesizer.
  - name: Monitors
    description: >-
      Monitors are custom observability dashboards for traces, runtime metrics,
      and logs. Each monitor holds widgets that chart one telemetry query. List
      the metrics, operations, and dimensions available to your workspace with
      `GET /v3/telemetry/capabilities`, or start from a preset with `GET
      /v2/monitors/presets`.
  - name: Notifiers
    description: Notifier destinations used to send delivery and workflow notifications.
  - name: Projects
    description: Projects organize resources within a workspace
  - name: Routing Rules
    description: >-
      Routing Rules conditionally select models and enforce request plugins for
      AI Gateway traffic. Rules are evaluated by ascending priority and may be
      scoped to a project or the whole workspace.
  - name: Threads
    description: Threads group related trace invocations and their aggregate usage
  - name: Skills
    description: >-
      Skills are modular instructions you can use to codify processes and
      conventions
  - name: Smart Routers
    description: >-
      Create and manage workspace Smart Routers. A Smart Router selects a model
      from an eligible pool for each request according to a quality, balanced,
      or cost profile.
  - name: Webhooks
    description: >-
      Create and manage webhooks that deliver workspace events to external HTTPS
      endpoints.
  - name: Workspaces
    description: >-
      A workspace is the tenant. Create is called from a user session during
      onboarding; Get, List, and Update are the public management surface.
  - name: Workspace Security
    description: >-
      Workspace-level domain verification and IP allowlist controls. These
      operations are restricted to workspace administrators.
  - name: Workspace Settings
    description: >-
      Workspace-level settings managed with a workspace credential. A workspace
      is the tenant, so these settings are a singleton — there is nothing to
      create or delete, only read and update.
  - name: Responses
  - description: Run agents on a cron cadence. Minimum firing interval is 1 hour.
    name: Agent Schedules
  - name: Embeddings
  - name: Telemetry
    description: >-
      Unified query envelope for traces, metrics, and logs. One request shape,
      one filter dialect, and one response shape per source, validated by a
      per-source registry.
  - description: Beta. Run typed classification questions against a classify model.
    name: Classify
  - description: Search Gateway with managed credits or BYOK.
    name: Web Search
  - description: Beta. Run classification decisions with the classify contract.
    name: Decisions
  - name: Users
    description: >-
      Workspace user administration. Requires a Management Key with user
      permissions or an authenticated workspace admin session. Standard API keys
      are not supported.
externalDocs:
  url: https://docs.orq.ai
  description: orq.ai Documentation
paths:
  /v3/experiments/{experiment_id}/runs/{run_id}/evaluators:
    post:
      tags:
        - Experiments
      summary: Add an eval column
      description: >-
        Links an existing evaluator. Each row gets one evaluator cell per task
        column. Config is updated at the evaluator source, not here.
      operationId: ExperimentEvalCreate
      parameters:
        - name: experiment_id
          in: path
          description: ID of the experiment.
          required: true
          schema:
            type: string
        - name: run_id
          in: path
          description: ID of the run.
          required: true
          schema:
            type: string
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateEvalColumnRequest'
        required: true
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Column'
        '401':
          description: >-
            Authentication required. See https://docs.orq.ai/reference/errors
            for the error codes.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
      x-code-samples:
        - lang: curl
          label: Core - Add an evaluator column
          source: >
            curl
            'https://my.orq.ai/v3/experiments/<experiment_id>/runs/<run_id>/evaluators'
            \
              --header 'Authorization: Bearer $ORQ_API_KEY' \
              --header 'Content-Type: application/json' \
              --data '{ "evaluator_id": "<evaluator_id>" }'
        - lang: python
          label: Python - Add an evaluator column
          source: |
            import os
            from orq_ai_sdk import Orq

            client = Orq(api_key=os.environ["ORQ_API_KEY"])

            column = client.experiments.create_eval(
                experiment_id="<experiment_id>",
                run_id="<run_id>",
                evaluator_id="<evaluator_id>",
            )
        - lang: typescript
          label: Node.js - Add an evaluator column
          source: |
            import { Orq } from '@orq-ai/node';

            const client = new Orq({ apiKey: process.env.ORQ_API_KEY });

            await client.experiments.createEval({
              experimentId: '<experiment_id>',
              runId: '<run_id>',
              evaluatorId: '<evaluator_id>',
            });
components:
  schemas:
    CreateEvalColumnRequest:
      required:
        - evaluator_id
      type: object
      properties:
        evaluator_id:
          type: string
          description: >-
            ID of the evaluator to add. Each row gets one evaluator cell per
            task
             column.
        position:
          type: integer
          description: 0-based position among the run's columns. Defaults to the end.
          format: int32
    Column:
      type: object
      properties:
        column_id:
          type: string
          description: >-
            Column ID. Dataset, prompt, evaluator and review columns keep their
            ID in
             new runs; agent columns get a new one.
        key:
          type: string
          description: |-
            Column key, derived from the display name: lowercased, with spaces
             replaced by underscores.
        display_name:
          type: string
          description: Column name.
        position:
          type: integer
          description: >-
            0-based position in the run, after the columns are grouped as
            dataset,
             task, job output, metric, evaluator and review columns.
          format: int32
        active:
          type: boolean
          description: |-
            Whether the column is shown in the AI Studio grid. False for hidden
             columns, such as the token metric columns.
        prompt:
          allOf:
            - $ref: '#/components/schemas/PromptTaskConfig'
          description: Set on prompt task columns.
        agent:
          allOf:
            - $ref: '#/components/schemas/AgentTaskConfig'
          description: Set on agent task columns.
        openresponse:
          allOf:
            - $ref: '#/components/schemas/OpenResponseTaskConfig'
          description: Set on task columns whose cells are filled outside orq.ai.
        evaluator:
          allOf:
            - $ref: '#/components/schemas/EvalColumnConfig'
          description: Set on evaluator columns.
        review:
          allOf:
            - $ref: '#/components/schemas/ReviewColumnConfig'
          description: Set on human review columns.
        dataset:
          allOf:
            - $ref: '#/components/schemas/DatasetColumnConfig'
          description: 'Set on the dataset columns: inputs, messages and expected output.'
        metric:
          allOf:
            - $ref: '#/components/schemas/MetricColumnConfig'
          description: 'Set on metric columns: cost, latency and token counts.'
        job_output:
          allOf:
            - $ref: '#/components/schemas/JobOutputColumnConfig'
          description: Set on evaluatorq job output columns.
        width:
          type: integer
          description: |-
            Column width in the AI Studio grid. Task columns default to 280;
             evaluator, review and metric columns to 200. 0 when unset.
          format: int32
      description: |-
        A column of a run. Exactly one of the config fields is set, matching the
         column type.
    ErrorResponse:
      type: object
      properties:
        message:
          description: Human-readable error message.
          type: string
        code:
          type: integer
          description: Numeric error code, when one is available.
        details:
          type: array
          items: {}
          description: Additional error details, when the service reports any.
      required:
        - message
    PromptTaskConfig:
      required:
        - prompt_config
      type: object
      properties:
        prompt_config:
          type: object
          additionalProperties: true
          description: |-
            Prompt to execute. Execution reads `model` (required), `provider`,
             `messages` and `model_parameters` such as `temperature`, `max_tokens` and
             `response_format`.
        messages_source:
          $ref: '#/components/schemas/MessagesSource'
          description: >-
            Messages sent to the model. `MESSAGES_SOURCE_PROMPT_CONFIG`: the
            prompt's
             messages only. `MESSAGES_SOURCE_MESSAGES_COLUMN`: the row's dataset
             messages only. `MESSAGES_SOURCE_COMBINED`: the prompt's messages followed
             by the row's messages. Defaults to `MESSAGES_SOURCE_PROMPT_CONFIG`.
        engine:
          type: string
          description: >-
            Template engine for variables in the messages: `text` (default),
            `jinja`
             or `mustache`.
        tools:
          type: array
          items:
            type: object
            additionalProperties: true
          description: Tools saved with the column.
        knowledge_bases:
          type: array
          items:
            type: object
            additionalProperties: true
          description: |-
            Knowledge bases searched on each execution, as `{knowledge_id,
             configuration}` with a configuration `type` of `last_user_message` or
             `query`. The retrieved context is available as `{{knowledge_retrieval}}`;
             when the prompt does not use it, it is appended to the system message.
        metadata:
          type:
            - object
            - 'null'
          additionalProperties: true
          description: >-
            Metadata saved with the column. Null when the column was saved
            without
             metadata.
      description: Configuration of a prompt task column.
    AgentTaskConfig:
      type: object
      properties:
        agent_key:
          type: string
          description: Key of the agent to run. Required.
        messages_source:
          $ref: '#/components/schemas/MessagesSource'
          description: >-
            Messages sent to the agent. `MESSAGES_SOURCE_MESSAGES_COLUMN`: the
            row's
             dataset messages. Any other value: `messages` from this config. System
             messages are dropped, since the agent's instructions provide them.
        messages:
          type: array
          items:
            type: object
            additionalProperties: true
          description: >-
            Conversation sent to the agent when `messages_source` is not the
            messages
             column.
        engine:
          type: string
          description: >-
            Template engine for variables in the messages: `text` (default),
            `jinja`
             or `mustache`.
        parent_id:
          type: string
          description: Saved with the column; not used during execution.
        agent_tag:
          type: string
          description: Agent version tag. When set, the column runs that tagged version.
      description: Configuration of an agent task column.
    OpenResponseTaskConfig:
      type: object
      properties: {}
      description: |-
        A task column whose cells are filled outside orq.ai, such as by an
         evaluatorq upload. It is never executed.
    EvalColumnConfig:
      type: object
      properties:
        evaluator_id:
          type: string
          description: ID of the evaluator.
        evaluator_name:
          type: string
          description: Evaluator display name.
        evaluator_type:
          type: string
          description: Evaluator type, such as `llm_eval` or `python_eval`.
        evaluator_output_type:
          type: string
          description: Type of value the evaluator returns, such as `number`.
      description: |-
        Configuration of an evaluator column. Name and types are read from the
         evaluator.
    ReviewColumnConfig:
      type: object
      properties:
        human_eval_id:
          type: string
          description: ID of the human review definition.
        human_eval_name:
          type: string
          description: Review name; the same as the column's display name.
        human_eval_type:
          type: string
          description: >-
            Value type the review accepts: `range`, `single_select`,
            `multi_select`, `text` or `correction`. Empty accepts
             any value.
      description: Configuration of a human review column.
    DatasetColumnConfig:
      type: object
      properties:
        column_type:
          type: string
          description: >-
            `inputs`, `messages` or `expected_output`. Dataset cells are
            read-only.
      description: Configuration of a dataset column.
    MetricColumnConfig:
      type: object
      properties:
        metric_key:
          type: string
          description: >-
            Metric shown: `cost`, `latency`, `ttft`, `input_tokens`,
            `output_tokens`
             or `reasoning_tokens`.
      description: Configuration of a metric column.
    JobOutputColumnConfig:
      type: object
      properties:
        job_name:
          type: string
          description: Name of the evaluatorq job.
      description: >-
        Output of one evaluatorq job; the column holds the text each job
        produced.
    MessagesSource:
      type: string
      enum:
        - MESSAGES_SOURCE_UNSPECIFIED
        - MESSAGES_SOURCE_PROMPT_CONFIG
        - MESSAGES_SOURCE_MESSAGES_COLUMN
        - MESSAGES_SOURCE_COMBINED
  securitySchemes:
    ApiKey:
      type: http
      scheme: bearer
      bearerFormat: JWT

````

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