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GET
/
v2
/
evaluators
/
{evaluator_id}
Get evaluator
curl --request GET \
  --url https://api.arize.com/v2/evaluators/{evaluator_id} \
  --header 'Authorization: Bearer <token>'
{
  "id": "RXZhbHVhdG9yOjEyOmFCY0Q=",
  "name": "Hallucination Eval",
  "description": "Detects hallucinated content in LLM responses",
  "type": "template",
  "space_id": "U3BhY2U6NDkzOkJaSkc=",
  "created_at": "2026-02-16T22:05:47.900Z",
  "updated_at": "2026-02-16T22:05:48.150Z",
  "created_by_user_id": "VXNlcjoxOm5OYkM=",
  "version": {
    "id": "RXZhbHVhdG9yVmVyc2lvbjoxMDpYeVp3",
    "evaluator_id": "RXZhbHVhdG9yOjEyOmFCY0Q=",
    "commit_hash": "a3b1c9e4f7d2a0518e6c3bb9217f87d1c4e810f2",
    "commit_message": "Initial version",
    "type": "template",
    "template_config": {
      "name": "hallucination",
      "template": "You are an evaluation assistant...",
      "include_explanations": true,
      "use_function_calling_if_available": true,
      "classification_choices": {
        "hallucinated": 0,
        "factual": 1
      },
      "direction": "maximize",
      "data_granularity": "span",
      "llm_config": {
        "ai_integration_id": "TGxtSW50ZWdyYXRpb246MTI6YUJjRA==",
        "model_name": "gpt-4o",
        "invocation_parameters": {
          "temperature": 0
        },
        "provider_parameters": {}
      }
    },
    "created_at": "2026-02-16T22:05:48.143Z",
    "created_by_user_id": "VXNlcjoxOm5OYkM="
  }
}

Documentation Index

Fetch the complete documentation index at: https://arize-ax.mintlify.dev/docs/llms.txt

Use this file to discover all available pages before exploring further.

Authorizations

​
Authorization
string
header
required

Most Arize AI endpoints require authentication. For those endpoints that require authentication, include your API key in the request header using the format

Path Parameters

​
evaluator_id
string
required

The evaluator global ID (base64) A universally unique identifier

Example:

"RW50aXR5OjEyMzQ1"

Query Parameters

​
version_id
string

Return the evaluator with this specific version (base64 global ID). If omitted, returns the latest version. A universally unique identifier

Example:

"RW50aXR5OjEyMzQ1"

Response

Returns an evaluator with a resolved version

An evaluator defines reusable evaluation logic that can be attached to evaluation tasks. The type field determines the kind of evaluation: template (LLM-based template evaluation) or code (custom code evaluation).

​
id
string
required

The unique identifier for the evaluator

​
name
string
required

The name of the evaluator

​
type
enum<string>
required

The evaluator type: template (LLM-based) or code (managed built-in evaluators or custom Python code — both are subtypes of code, discriminated by the nested CodeConfig.type = managed | custom). Applies to both the parent Evaluator.type field and every version's type discriminator — a version's type must always match its parent evaluator's type.

Available options:
template,
code
​
space_id
string
required

The unique identifier for the space the evaluator belongs to

​
created_at
string<date-time>
required

When the evaluator was created

​
updated_at
string<date-time>
required

When the evaluator was last updated

​
created_by_user_id
string | null
required

The unique identifier for the user who created the evaluator

​
version
object
required

The resolved version of the evaluator

​
description
string | null

The description of the evaluator