Define a Golem tool in Scala

Annotate the definition trait and implementation class. The build plugin generates registration, metadata, and typed client sources:

import golem.runtime.annotations.{toolDefinition, toolImplementation}
 
@toolDefinition(version = "1.0.0")
trait Echo {
  def echo(value: String): String
}
 
@toolImplementation()
final class EchoImpl extends Echo {
  override def echo(value: String): String = value
}

Use @arg, @command, @constraint, @result, and @annotations when the command-line surface needs explicit metadata. Custom values require zio.blocks.schema.Schema. Keep scalacOptions += "-experimental" enabled for macro annotations and never edit generated client or registration sources.