Add missing comments

experimental/configsource/factory.go

@@ -50,4 +50,5 @@ type Factory interface {
 	CreateConfigSource(ctx context.Context, params CreateParams, cfg ConfigSettings) (ConfigSource, error)
 }
 
+// Factories is a map from types of ConfigSource and the respective Factory for the type.
 type Factories map[config.Type]Factory

experimental/configsource/settings.go

@@ -18,6 +18,8 @@ import (
 	"go.opentelemetry.io/collector/config"
 )
 
+// ConfigSettings is an interface that must be supported by all configuration objects
+// of ConfigSource implementations.
 type ConfigSettings interface {
 	config.NamedEntity
 }

experimental/configsource/vaultconfigsource/config.go

@@ -21,6 +21,7 @@ import (
 	"go.opentelemetry.io/collector/experimental/configsource"
 )
 
+// Config holds the configuration settings for Vault ConfigSource objects.
 type Config struct {
 	*configsource.Settings
 	// Endpoint is the address of the Vault server, typically it is set via the

experimental/configsource/vaultconfigsource/factory.go

@@ -80,6 +80,7 @@ func (v *vaultFactory) CreateConfigSource(_ context.Context, params configsource
 	return newConfigSource(params.Logger, vaultCfg)
 }
 
+// NewFactory creates a factory for Vault ConfigSource objects.
 func NewFactory() configsource.Factory {
 	return &vaultFactory{}
 }