## Get Evaluation Data Schema

`evaluations.retrieve_schema(strevaluation_id, EvaluationRetrieveSchemaParams**kwargs)  -> EvaluationSchemaResponse`

**get** `/v5/evaluations/{evaluation_id}/schema`

Describe the data schema of an evaluation's items.

Inspects the item `data` and task-result fields and returns each discovered field with its
flattened key path, JSON type, source, and the number of items containing it, ordered
alphabetically by field name. For large evaluations the schema may be inferred from a sample of
items, in which case `is_sampled` is set and `sample_size` reports how many were analyzed. Set
`include_archived` to include archived items in the analysis.

### Parameters

- `evaluation_id: str`

- `include_archived: Optional[bool]`

  Include archived items in schema analysis

### Returns

- `class EvaluationSchemaResponse: …`

  Schema information for an evaluation's item data structure

  - `evaluation_id: str`

    The ID of the evaluation

  - `fields: List[Field]`

    List of all discovered fields, ordered alphabetically by field_name

    - `data_type: str`

      JSON type: 'string', 'number', 'boolean', 'object', 'array', or 'null'

    - `field_name: str`

      The flattened JSON key path (e.g., 'metadata.category')

    - `item_count: int`

      Number of evaluation items containing this field

    - `source: Literal["data", "task_result_cache"]`

      The source of the field: 'data' or 'task_result_cache'

      - `"data"`

      - `"task_result_cache"`

    - `object: Optional[Literal["field_schema"]]`

      - `"field_schema"`

  - `total_items: int`

    Total number of evaluation items

  - `is_sampled: Optional[bool]`

    Whether schema was computed from a sample of items (for large evaluations)

  - `object: Optional[Literal["evaluation_schema"]]`

    - `"evaluation_schema"`

  - `sample_size: Optional[int]`

    Number of items sampled for schema inference, if applicable

### Example

```python
import os
from scale_gp_beta import SGPClient

client = SGPClient(
    api_key=os.environ.get("SGP_API_KEY"),  # This is the default and can be omitted
)
evaluation_schema_response = client.evaluations.retrieve_schema(
    evaluation_id="evaluation_id",
)
print(evaluation_schema_response.evaluation_id)
```

#### Response

```json
{
  "evaluation_id": "evaluation_id",
  "fields": [
    {
      "data_type": "data_type",
      "field_name": "field_name",
      "item_count": 0,
      "source": "data",
      "object": "field_schema"
    }
  ],
  "total_items": 0,
  "is_sampled": true,
  "object": "evaluation_schema",
  "sample_size": 0
}
```