SKILL.md
Kotlin API Design Review
Naming Rules
- Clear at point of use
- Omit needless words
lowerCamelCase: properties, functions, variablesUpperCamelCase: classes, interfaces, objectsUPPERSNAKECASE: constants- Booleans:
is,has,can,shouldprefix - Collections: plural names (
users, notuserList)
Compose-specific Naming
- Composable functions returning
Unit: use PascalCase nouns (e.g.,UserProfileCard, notuserProfile) - Avoid spaces and backticked identifiers in function names, especially in public APIs (discouraged by Kotlin conventions)
Common Issues
| Issue | Fix |
|---|---|
var visible |
var isVisible |
fun getData() |
fun getUserName() |
var nameString |
var name |
userList |
users |
| Composable named like regular function | Rename to PascalCase noun (ProfileScreen) |
| Implicit return type in library | Add explicit : String |
Function Design
- Named parameters for clarity beyond first param
- Default parameters at end
- Suspend functions for async operations
- Extension functions for utility methods
- Operator overloading when semantically appropriate
- Prefer properties over parameterless functions when the operation is cheap and non-throwing
- Use named arguments + trailing commas for multi-parameter calls in public APIs
Return Types
- Nullable when null is meaningful
- Result<T> for failable operations
- Flow<T> for streams
- sealed class for finite states
- Explicitly declare return types in public library APIs (even if inferable)
Data Classes
- Use for data transfer objects
- Immutable by default (val over var)
- Copy function for updates
- Destructuring support
Public API / Library
- Provide KDoc for all public members
- Use
@JvmNamefor interop-friendly naming - Use backing properties (
_internalValue) for observed state - Consider type aliases for repeated complex function types
Severity
- 🔴 Critical: Violates conventions
- 🟡 Improvement: Could be clearer
- 🟢 Enhancement: Optional polish