# JSON Schema Contract: Deterministic Article Content Selection

**Branch**: `004-deterministic-content-selection` | **Date**: 2026-08-20 | **Spec**: [spec.md](../spec.md)

---

## 1. Input JSON Schema

O arquivo de entrada deve conter uma lista de artigos sob a chave `articles`.

```json
{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "type": "object",
  "required": ["articles"],
  "properties": {
    "articles": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "trafilatura": {
            "type": "object",
            "properties": {
              "text": { "type": ["string", "null"] },
              "error": { "type": ["string", "null"] }
            }
          },
          "newspaper4k": {
            "type": "object",
            "properties": {
              "text": { "type": ["string", "null"] },
              "error": { "type": ["string", "null"] }
            }
          },
          "readability": {
            "type": "object",
            "properties": {
              "cleaned_text": { "type": ["string", "null"] },
              "error": { "type": ["string", "null"] }
            }
          }
        }
      }
    }
  }
}
```

---

## 2. Output JSON Schema

O arquivo de saída mantém todos os campos, metadados e ordem originais, adicionando obrigatoriamente `selected_extractor`.

```json
{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "type": "object",
  "required": ["articles"],
  "properties": {
    "articles": {
      "type": "array",
      "items": {
        "type": "object",
        "required": ["selected_extractor"],
        "properties": {
          "selected_extractor": {
            "type": "string",
            "enum": ["trafilatura", "newspaper4k", "readability"]
          },
          "trafilatura": { "type": "object" },
          "newspaper4k": { "type": "object" },
          "readability": { "type": "object" }
        }
      }
    }
  }
}
```