Engine Services
===============

The Engine Services layer provides AI/ML pipeline capabilities:

* **Pipeline Service** - Manages Haystack pipeline definitions, validation, and execution (sync/async)
* **Training Service** - Trains binary SVM classifiers using Haystack training pipelines
* **Prompt Service** - CRUD operations for LLM prompt templates stored in the database
* **Token Usage Service** - Extracts and tracks LLM token usage from pipeline executions

All AI/ML workflows are implemented as Haystack pipelines. The ``PipelineService`` is the central orchestrator that builds and executes pipelines from YAML definitions, while delegating component validation to the ``ComponentRegistry`` and document validation to the ``DocumentContract``.

.. toctree::
   :maxdepth: 2
   :caption: Engine Services

   pipeline_service
   training_service
   prompt_service
   token_usage_service