> 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/es/web-scraper-api/features/custom-parser/writing-instructions-manually.md).

# Escritura manual de instrucciones

Mira cómo escribir instrucciones de análisis manualmente para manejar casos extremos o personalizar la lógica de análisis.

Si bien Custom Parser te ayuda a automatizar el análisis de datos con funciones impulsadas por IA, también puedes escribir instrucciones de análisis manualmente usando expresiones CSS y XPath. Esto te da la opción de **gestionar casos límite** o **personalizar la lógica de análisis** para escenarios específicos.

Custom Parser requiere estos parámetros obligatorios al crear un trabajo:

* `parse` establecer en `verdadero`
* `parsing_instructions` que contiene un objeto JSON con tus reglas de extracción

Una vez que estés satisfecho con tu lógica de análisis personalizada, puedes guardar las instrucciones como un [preajuste del analizador](/products/es/web-scraper-api/features/custom-parser/parser-presets.md).

Consulta nuestras guías completas a continuación, donde puedes encontrar ejemplos prácticos, buenas prácticas para expresiones XPath y una referencia completa de todas las funciones de análisis disponibles.

{% content-ref url="/pages/6fd3569c2400a7c36b3fda738cd4df91a4fa24ac" %}
[Ejemplos de instrucciones de análisis](/products/es/web-scraper-api/features/custom-parser/writing-instructions-manually/parsing-instruction-examples.md)
{% endcontent-ref %}

{% content-ref url="/pages/3a03dac151c6640f8e582e5735cba3337282067c" %}
[Consejos para escribir expresiones XPath](/products/es/web-scraper-api/features/custom-parser/writing-instructions-manually/tips-for-writing-xpath-expressions.md)
{% endcontent-ref %}

{% content-ref url="/pages/d79a67118b9a83d04625db94c5a04803156f17bd" %}
[Lista de funciones de análisis](/products/es/web-scraper-api/features/custom-parser/writing-instructions-manually/list-of-functions.md)
{% endcontent-ref %}

{% content-ref url="/pages/eb1e80d0a1c7f2ff775e97e19e98b9af8eae4599" %}
[Ejemplos de funciones de análisis](/products/es/web-scraper-api/features/custom-parser/writing-instructions-manually/list-of-functions/function-examples.md)
{% endcontent-ref %}


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