About Spring Boot for starters exists the Build Systems – Starters section where shows the following tables:

• Table 1. Spring Boot application starters
• Table 2. Spring Boot production starters
• Table 3. Spring Boot technical starters

Where each starter practically is based with the spring-boot-starter-<something> pattern. It because the first one is spring-boot-starter (perhaps It could had been named as spring-boot-starter-core … well it is other history)

Now exists Developer Tools where its dependency is declared as:

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-devtools</artifactId>
        <optional>true</optional>
    </dependency>
</dependencies>

Observe it is spring-boot-devtools and not as spring-boot-starter-devtools. Why this difference? Even more: this starter does not appear in the Spring Boot application starters table and neither in the others too.