Writes business logic as Krystal Vajrams — the composable, concurrently-executed unit of logic in flipkart-incubator/Krystal (vajram-java-sdk + krystex runtime). Covers ComputeVajramDef vs IOVajramDef, _Inputs/_InternalFacets, @IfAbsent optionality, @Dependency wiring, @Resolve resolvers (fan-out via FanoutCommand, skips via One2OneCommand), @Output/@Output.Batched+@Output.Unbatch, writing Vajram Traits (@Trait/TraitDef interfaces with no implementation) and dispatching among their conforming Vajrams via static/qualifier dispatch (@Qualifier + TraitBinder) or predicate dispatch (@UseForPredicateDispatch + PredicateDispatchPolicy), and tests via VajramGraph/KrystexGraph/VajramKryonExecutor (incl. VajramTestHarness mocking and wiring trait dispatch policies). Use whenever adding/changing a Vajram, defining or implementing a Trait, modeling logic as a DAG node, wiring a dependency, adding fan-out/batching, or writing/debugging a vajram-graph test — even if the user just says "add a vajram for X", "make this plug
Defines structured data models — request/response payloads, nested value objects, and enums — as Krystal `@ModelRoot` interfaces/enums (`com.flipkart.krystal.model.**` in krystal-common) in the Krystal framework (flipkart-incubator/Krystal). Covers `@ModelRoot` (type=REQUEST/RESPONSE, pure, builderExtendsModelRoot), field annotations (`@SerialId`, `@IfAbsent`, `@Nullable`/`Optional`), `@SupportedModelProtocol` (PlainJavaObject/Json/Protobuf3/Fory) and the generated `_Immut`/`_ImmutPojo`/`_ImmutJson`/`_ImmutProto`/`_ImmutFory` builders, enum model roots (`EnumModel`, `UNKNOWN`-first rule), model purity, and nested-model/collection constraints. Use whenever the user wants to define/change a data model, DTO, request or response shape, a nested/enum field type, or asks "what protocols/serde does this model support" in a Krystal-based repo — even if they just say "add a field to X" or "model this payload" without naming `@ModelRoot`. Not for Vajram business logic (`_Inputs`/`_InternalFacets`/`@Dependency`/`@Resolv
Models SQL table schemas AND writes SELECT/INSERT queries using the vajram-sql plugin of the Krystal framework (flipkart-incubator/Krystal). Covers @Table/@ModelRoot model interfaces (columns, @PrimaryKey, @UniqueKey, @ForeignKey/@IncomingForeignKey, nullability, defaults, JSON columns, matching raw DDL) and query traits — @Selection projections, @WHERE/ColumnPredicate/SqlOrPredicate filters, @SQL @SELECT/@INSERT @Trait definitions with @LIMIT/@ORDER/@ReturnOnInsert. Use whenever the user wants to define/change a SQL table, or fetch/insert rows, look up a record, add a query, or write a repository-style method against a Krystal/Vajram data layer — even if they just say "add a table for X" or "write a query to fetch Z" without naming vajram-sql, as long as the repo uses Krystal/Vajram. Not for generic (non-Krystal) DB work, or UPDATE/DELETE (no codegen support yet).