Spec

Also called: specification, specs, spec doc

A written description of what is being built and why, for work too big to finish in one session. It describes the goal rather than every step, and it is usually split into smaller tickets. A clear spec is one of the most useful things a founder can hand an agent or a contractor.

For example: Before a weekend of AI-assisted building, a founder writes a two-page spec for the booking feature and splits it into six tickets.