Commands declare their interface by implementing four parameter list methods:

• getRequiredNamedParameterList()
• getOptionalNamedParameterList()
• getRequiredParameterList()
• getOptionalParameterList()

Named parameters map to positional values (deploy production api), while Parameter definitions map to options and flags (--tag v1.2.3, --verbose).

¶Defining command contracts

public function getRequiredNamedParameterList():array {
	return [
		new NamedParameter("environment"),
	];
}

public function getOptionalNamedParameterList():array {
	return [
		new NamedParameter("service"),
	];
}

public function getRequiredParameterList():array {
	return [
		new Parameter(true, "tag", "t", "Release tag to deploy"),
	];
}

public function getOptionalParameterList():array {
	return [
		new Parameter(false, "dry-run", "d", "Preview only"),
		new Parameter(false, "verbose", "v", "Show extra detail"),
	];
}

¶Reading values in run()

$environment = (string)$arguments->get("environment");
$service = (string)$arguments->get("service", "web");
$tag = (string)$arguments->get("tag");
$dryRun = $arguments->contains("dry-run");
$verbose = $arguments->contains("verbose");

The get($key, $default) pattern allows simple defaults for optional values, while contains($key) is used for boolean flags.

When required values are missing, command execution fails with explicit exceptions (MissingRequiredParameterException, MissingRequiredParameterValueException) and usage text is printed automatically.

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