> For the complete documentation index, see [llms.txt](https://developers.oxylabs.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers.oxylabs.io/products/pt-br/web-scraper-api/features/custom-parser/writing-instructions-manually.md).

# Escrevendo instruções manualmente

Embora o Custom Parser ajude você a automatizar a análise de dados com recursos baseados em IA, você também pode escrever instruções de parsing manualmente usando expressões CSS e XPath. Isso lhe dá a opção de **tratar casos de borda** ou **personalizar a lógica de parsing** para cenários específicos.

O Custom Parser requer estes parâmetros obrigatórios ao criar um job:

* `parse` definido como `verdadeiro`
* `parsing_instructions` contendo um objeto JSON com suas regras de extração

Quando estiver satisfeito com sua lógica de parsing personalizada, você pode salvar as instruções como uma [predefinição de parser](/products/pt-br/web-scraper-api/features/custom-parser/parser-presets.md).

Confira nossos guias completos abaixo, onde você encontra exemplos práticos, boas práticas para expressões XPath e uma referência completa de todas as funções de parsing disponíveis.

{% content-ref url="/pages/5692a1f6241d30d2c68074029f7bcf282b1d041f" %}
[Exemplos de instruções de parsing](/products/pt-br/web-scraper-api/features/custom-parser/writing-instructions-manually/parsing-instruction-examples.md)
{% endcontent-ref %}

{% content-ref url="/pages/2d23f8c3d3784854abed7f6ba85ec3d5950e0942" %}
[Dicas para escrever expressões XPath](/products/pt-br/web-scraper-api/features/custom-parser/writing-instructions-manually/tips-for-writing-xpath-expressions.md)
{% endcontent-ref %}

{% content-ref url="/pages/69a77f9f80386f5349af2e7706811cf2b108609a" %}
[Lista de funções de parsing](/products/pt-br/web-scraper-api/features/custom-parser/writing-instructions-manually/list-of-functions.md)
{% endcontent-ref %}

{% content-ref url="/pages/a86948f4a6e8c071ccf2215cba22e3f1097af371" %}
[Exemplos de funções de parsing](/products/pt-br/web-scraper-api/features/custom-parser/writing-instructions-manually/list-of-functions/function-examples.md)
{% endcontent-ref %}


---

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