fil/docs/snippets/elixir/plugins/pdf_metadata_extractor.md

Custom PDF metadata extractor implementation is not available in the Elixir binding. Document extractors must be implemented in Rust using the DocumentExtractor trait.

To implement a custom PDF metadata extractor in Rust:

1. Implement the Plugin and DocumentExtractor traits
2. Add support for PDF MIME types: application/pdf
3. Use a PDF library (e.g., pdfium-render, pdf crate) to extract metadata
4. Register the extractor in the Rust core

See the Rust plugin documentation for implementing custom DocumentExtractor plugins for PDF files.