Engineers write prompts as part of the job now, and being able to refer to them in an efficient manner is a valuable improvement to your workflow. Skip pasting file contents into Claude entirely: open find-file (C-x C-f) to surface the path Emacs already knows, select it and cut it …

When Claude delegates a prompt to a sub-agent, it pastes the whole prompt text into that sub-agent's context by default — thousands of tokens, duplicated, every time. Tell it to hand over a file reference instead of the copied text, and that one change alone can cut input tokens 25-40%.