Specialized services 

These paths serve translation, image, speech or document operations rather than a generic chat request. Credential lookup, pricing units and result types can differ. See Verifying the specialized services for configuration and explicit quota-spending checks.

• Specialized\Translation\TranslatorInterface is an extension point for registered translators. It requires identity/name, static priority, availability, language-pair support, language discovery, single and batch translation, and detection. Translation returns TranslatorResult. Prefer TranslationService as the consumer facade.
• Specialized\Translation\TranslatorRegistryInterface supplies registered translators; registration does not mean usable credentials exist.
• Specialized\Image\ImageGeneratorInterface abstracts image generation for consumers. Match its result and options to the selected generator; not every generator implements every provider-specific option.
• Specialized\Document\PdfRasterizerInterface provides document rasterization. It needs the configured local runtime; it is not an LLM.
• Specialized\Speech\TextToSpeechService and WhisperTranscriptionService are public concrete services with SpeechSynthesisResult and TranscriptionResult. This revision has no separate public speech-service interface to recommend.

The @api classification is per type/member; an interface's existence does not automatically make every implementation a stable extension point. See API stability. Keep provider credentials in nr-vault and supply a trusted budget/actor context rather than treating a caller-supplied user ID as authentication.