Implement read queries — paginated lists, search/filter/sort, and single-entity fetches — the FSH way (DbContext LINQ + PagedResponse). Use when adding GET endpoints. See also add-feature.
Write tests for an FSH feature — xUnit + Shouldly + NSubstitute + AutoFixture, with naming and AAA conventions. Use when adding unit/handler/validator/entity tests. Full rules in .agents/rules/testing.md + integration-testing.md.
Publish a cross-module integration event via the Outbox and handle it idempotently in another module. Use when one module must react to something that happened in another. See .agents/rules/eventing.md.
Create a new module (bounded context) — runtime + Contracts projects, IModule, DbContext, permissions, migrations, and the four registration sites. Use when adding a distinct business domain. For a feature in an existing module, use add-feature.
Add a domain entity/aggregate with EF configuration and a migration to an existing FSH module. Use when adding a new database-backed entity. Pairs with add-feature and create-migration.
Add a vertical-slice feature (command/query + handler + validator + endpoint) to an existing FSH module. Use when adding an API endpoint or business operation to a module that already exists.
Build a capability end-to-end — backend vertical slice (Contracts→handler→validator→endpoint) AND the React page wired to it. Use when delivering a user-facing feature across API + UI. Composes add-feature + add-react-page.
Add a new permission end-to-end — server constant + endpoint gate, and (admin app) mirror it into the permissions catalog + route guard. Use when a new endpoint needs authorization. See modules/identity.md + frontend/admin.md.