Word (docx) skill

Producing a Word document that opens correctly and respects a house style is a structural task, not a writing task. The `.docx` format is a zipped XML package where styles, numbering, headers and revision marks all live in specific places, and a model emitting XML by hand gets it subtly wrong in ways that only surface when someone opens the file. This skill delegates the structure to code and keeps the model on the content.

For a security team the interesting property of `.docx` is how much it carries that is not the visible text. Tracked changes and comments preserve deleted content — including the paragraph somebody removed precisely because it should not be shared. Document properties retain authors, revision counts, and sometimes file paths. An agent reading a document reads all of it, and an agent *generating* one can propagate metadata into a file that then leaves the organisation.

The reverse direction matters as much: a contract or policy document received from outside is untrusted input. Its body text, comments, and field codes are all places an instruction can sit where a human reviewer will not see it, and 'summarise this agreement' is exactly the request that puts it in front of a model holding other tools.

As with the other document skills, the reviewable artifact is the bundled code plus the instructions, and the useful control is where it runs rather than whether it runs.