Definition
Plain language
A tool that installs and keeps track of the outside software your program depends on.
As stated in the literature
System that resolves, downloads, and version-pins software dependencies; pinning by hash so an approved artifact can't be silently swapped is the analogy the paper draws for MCP tool definitions.
Also called: package managers
Why it matters: Without it you'd have to hunt down and update every piece of outside software by hand, and pinning versions keeps an approved piece from being quietly replaced with something malicious.
For example, when you install one library it might automatically fetch the dozen other pieces of software that library needs to run.
Heard on the show
“One: build empty software packages with the right names, so the package manager reports the required drivers as "installed" — empty shells, no actual functionality.”Episode 124 — A Cheap Model With the Blueprints Beats Expensive Models Working Blind