Anthropic added PDF support to their Claude API this morning, I have a new release of the llm-claude-3 plugin that supports that as a new attachment type:

llm install llm-claude-3 --upgrade
llm -m claude-3.5-sonnet 'extract text' -a mydoc.pdf

Details: https://simonwillison.net/2024/Nov/1/claude-api-pdf-support-beta/