A new prototype called Pasted File Editor replicates a feature found in Claude's apps, where large blocks of pasted text are automatically converted into file attachments. Built using Codex desktop, the tool also lets users open files directly—displaying images as thumbnails—or drag files onto the text area.

Simon Willison highlights a feature in Claude.ai where pasted text is automatically converted into a file attachment. He built a prototype using Codex desktop to replicate this functionality, adding direct file opening and drag-and-drop support. The post also mentions his sponsorship offer for a monthly LLM developments digest.