Kotlin Autocomplete

Kotlin Autocomplete Skill

You have access to accurate, project-specific Kotlin type information through autocomplete metadata generated by the kotlin-autocomplete-gradle-plugin.

When to Use This Skill

Use this skill when:

• Writing Kotlin code and need to know what methods/​properties are available on a type
• The user asks "what can I do with X type?" or "what methods does X have?"
• Verifying if a specific member exists on a type
• Exploring Kotlin APIs (stdlib, coroutines, or project-specific)
• You're unsure about method signatures or available extensions

How It Works

The autocomplete metadata is generated by running ./​gradlew buildAutocomplete in a Kotlin project. This creates JSON files in build/​autocomplete/ containing:

• All public properties and methods with full signatures
• Extension functions and properties
• Both standard library and project-specific types

Querying Type Information

Use the helper script to query type information:

.claude/​skills/​scripts/​kotlin-autocomplete-lookup.sh "fully.qualified.TypeName"

Examples:

# Standard library types
.claude/​skills/​scripts/​kotlin-autocomplete-lookup.sh "kotlin.String"
.claude/​skills/​scripts/​kotlin-autocomplete-lookup.sh "kotlin.collections.List"

# Coroutines types
.claude/​skills/​scripts/​kotlin-autocomplete-lookup.sh "kotlinx.coroutines.flow.Flow"

# Project types
.claude/​skills/​scripts/​kotlin-autocomplete-lookup.sh "com.example.User"

Response Format

When presenting autocomplete information, format it clearly:

Type: kotlin.String

Members:
- val length: kotlin.Int
- fun substring(startIndex: kotlin.Int): kotlin.String
- fun lowercase(): kotlin.String

Extensions:
- fun toSnakeCase(): kotlin.String
- val firstChar: kotlin.Char?

Total: 3 members, 2 extensions

Prerequisites

The Kotlin project must have:

1. Applied the plugin in build.gradle.kts:

   plugins {
       id("com.lightningkite.kotlin-autocomplete") version "0.0.1-1"
   }
   

2. Generated metadata: ./​gradlew buildAutocomplete
3. Metadata exists in build/​autocomplete/ directory

Important Notes

• Type names must be fully qualified: Use kotlin.String not String
• Only public members are included: Internal and private members are excluded
• Extensions on Any/​Any? are filtered: Too generic to be useful
• Fast lookups: Index-based queries are nearly instant

If Metadata Not Found

If autocomplete metadata doesn't exist:

1. Suggest running ./​gradlew buildAutocomplete
2. Verify the plugin is applied
3. Check if the type name is correct
4. Fall back to general Kotlin knowledge, but note it may not be project-specific

Benefits

• No hallucinations: All information comes from actual compiled code
• Project-aware: Includes custom extensions and project types
• Always up-to-date: Regenerate when code changes
• Complete signatures: Full parameter types and return types

Example Workflow

User: "What can I do with a Flow?"

1. Run: .claude/​skills/​scripts/​kotlin-autocomplete-lookup.sh "kotlinx.coroutines.flow.Flow"
2. Parse the output
3. Present available operations in a clear format
4. Suggest common patterns based on the available members

This ensures you provide accurate, project-specific Kotlin guidance!