plan-architect

To generate a high-level architecture document, provide a shaping document path to produce docs/plans/00-architecture.md with component breakdowns, mermaid diagrams, deployment modes, and decision rationales for your software system.

A plan index for multi-sub-plan projects is structured by optionally creating docs/plans/00-plan-index.md, which coordinates sub-teams by providing a shared design basis and tracking future sub-plan drafting.

System design documentation includes deployment considerations and decision rationales by generating an architecture doc that outlines deployment modes and records the reasoning behind specific architecture decisions to guide implementation.

Yes, you need a shaping document before drafting architecture and sub-plans, because the phase-driven workflow reads these shaping docs to resolve questions and decide whether a single or multi-plan approach is required.

Yes, you can use mermaid diagrams to visualize component breakdowns, as the architecture plan generation process explicitly produces mermaid diagrams within the docs/plans/00-architecture.md file to guide implementation.

You should use a single architecture plan versus a multi-sub-plan approach after writing the architecture and evaluating whether multiple sub-plans are required to coordinate sub-teams, deciding based on project scale.