word

A stateful Word (.docx) engine an agent edits in place - not a file it regenerates. Opens an existing .docx behind a handle and mutates it through addressable Blocks (paragraphs, headings, tables) instead of the 'emit a whole new file' pattern that discards a document's template, headers, footers, page numbering and images on every edit. Every Block gets an opaque id plus its own computed Number (resolved by walking numId/ilvl through the style chain, never guessed from run text), so 'the last table' or 'section 13.2' addresses one Block, not the whole document. Named styles are the primary text operation - an undefined style name fails STYLE_NOT_FOUND with the document's real style inventory rather than a fuzzy match or an invented style; direct formatting (bold/size/color/font) is reachable only through one explicitly-named escape hatch. document.save backs up, writes to temp, verifies against the source by Part list and uncompressed content (never file size, which zip recompression alone shifts by design), then atomically renames - a failed verification leaves the original untouched. 18 tools across document lifecycle, outline/addressing, text, style, tables, headers/footers, media inventory, Revision/Comment reading, and Template discovery.