Packages

What you install

Each layer depends only on the layers above it in this table. There are no cycles.

Layer	Package	Role
Runtime	mas-runtime	The kernel, contracts, plugins and design patterns. Library only; the console script points at mas-ctl
Orchestration	mas-ctl	Builds and runs sessions: chat, run-mas, validate, compile, compose
Lab	mas-lab-core	Shared contracts and telemetry types
	mas-lab-bench	Runs benchmarks and analysis pipelines
	mas-lab-controller	A background service with an HTTP API, used by the web UI
	mas-lab	Installs the three above and provides the mas-lab command
Libraries	mas-library-standard	Flavours, overlays, infra bundles, built-in plugins
	mas-library-eval	Evaluation metrics consumed by pipeline steps
	mas-library-lab	Shared types and backend code for the lab and its UI
	mas-library-samples	Reference applications, datasets, tutorial fixtures
	mas-library-telemetry	Converts and replays traces, exports to OpenTelemetry
	mas-library-kg	Turns traces into a knowledge graph
	mas-library-skills	The skill catalogue and the tools that read skills
	mas-library-ioa	MCP client/server bridge

A lab is an experiment folder. A library is a folder with a library.yaml holding reusable applications, tools and plugins, referenced as name:path. The two are deliberately different things.

See the package map, the packages reference and labs vs libraries. Directories in a checkout are on Repo structure.