Structured Output Workbench

Example Presets

Validation Result

Found 5 issue(s).

Path $.price

Issue Missing required field.

Path $.extra

Issue Unexpected field.

Path $.attributes[0].rank

Issue Unexpected field.

Path $.in_stock

Issue Expected boolean but received string.

Path $.sku

Issue Expected string but received number.

Provider Patterns

Provider-agnostic prompt

Use the target JSON structure as the contract and reject extra keys.

Return JSON only.
Use the target JSON structure as the contract for keys, nesting, arrays, and value types.
Do not wrap the result in markdown.
Do not add extra keys.

Target structure:
{
  "sku": "abc-123",
  "price": 19.99,
  "in_stock": true,
  "attributes": [
    {
      "name": "color",
      "value": "blue"
    }
  ]
}

OpenAI Responses API

Use text.format with a strict JSON schema to request direct structured output.

from openai import OpenAI

client = OpenAI()

response = client.responses.create(
    model="gpt-5",
    input="Return the response in the required JSON shape.",
    text={
        "format": {
            "type": "json_schema",
            "name": "structured_output",
            "strict": True,
            "schema": {
              "type": "object",
              "properties": {
                "sku": {
                  "type": "string"
                },
                "price": {
                  "type": "number"
                },
                "in_stock": {
                  "type": "boolean"
                },
                "attributes": {
                  "type": "array",
                  "items": {
                    "type": "object",
                    "properties": {
                      "name": {
                        "type": "string"
                      },
                      "value": {
                        "type": "string"
                      }
                    },
                    "required": [
                      "name",
                      "value"
                    ],
                    "additionalProperties": false
                  }
                }
              },
              "required": [
                "sku",
                "price",
                "in_stock",
                "attributes"
              ],
              "additionalProperties": false
            },
        }
    },
)

print(response.output_text)

Anthropic prompt pattern

Paste the target structure verbatim and instruct the model to answer with JSON only.

You are returning structured data for a downstream parser.
Output JSON only.
Match the exact keys, nesting, and value types shown below.
If a field is unknown, return a valid placeholder of the same type.

Target structure:
{
  "sku": "abc-123",
  "price": 19.99,
  "in_stock": true,
  "attributes": [
    {
      "name": "color",
      "value": "blue"
    }
  ]
}

Structured Output Playground