Concepts

The building blocks every mast deployment touches, whether you run the daemon or embed the library. These pages explain how the pieces fit and why they are shaped that way; the reference section is where the exact fields, flags, and outcomes live.

If you’d rather see it work first, the offline quickstart runs the whole loop — inject, park, kill -9, resume — with no credentials in about five minutes.

Workloads and specialistsThe bundle as the unit of deployment, the roster it names, and what a specialist declares about itself — capability, model, budget, report contract.

DurabilityWhy a pause outlives the process that asked, what reconstruct-and-re-execute means for mutating tools, and how the effect log turns duplicate risk into a visible refusal.

Approvals and the write gateFour boundaries in front of a cluster change — capability split, mutation classification, the per-call gate, and the cluster's own RBAC — and what each does not cover.

Budgets and costTurn, wallclock, and dollar ceilings at both the workload and the specialist level, how spend is attributed, and the two limits worth knowing before you rely on a cap.

Tools and MCPThe tool catalog, per-specialist allowlists, and the default-deny-unknown mutation predicate — plus the silent failure mode an allowlist typo produces.

Providers and modelsGemini, Claude, and the offline fakes; picking a model per specialist across providers; and why an unresolvable override fails startup.

Interop surfacesA2A, AG-UI, and the mast-native attach protocol — three ways in, aimed at three different consumers. Which one you want, and when.