Progressive Disclosure
Loading agent context in stages - names and descriptions first, full bodies when relevant, linked files only as needed - so bundled context is effectively unbounded.
Plain English
Show the model the table of contents, and hand it the chapter only when it asks.
Example
A pdf skill ships as a name plus one-line description; when the user asks to fill a form, the agent reads the SKILL.md, and only then the referenced forms.md with field-level instructions.
Why it matters
It is the design principle underpinning Agent Skills, code mode, and tool search: stop asking 'will it fit in the window' and start asking 'what does the model need to see now'.