Architecture

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Module dependency graph
Request lifecycle: PromptEngine.build()
Class relationships
Extension points
Initialization order
Related pages

There is no CLI, web server, ORM, or plugin-discovery mechanism in this package. Extensibility is achieved through plain constructor injection (e.g. passing a custom ContextManager or extra Guardrail objects into PromptEngine) and the STRATEGY_REGISTRY dict.

Module dependency graph

ab_testing.py is the one module with no import dependency on the rest of the package — it operates on plain strings and an injected llm object, and only optionally introspects a rag_system via getattr/hasattr at runtime (see api/ab_testing).

Request lifecycle: `PromptEngine.build()`

Class relationships

Extension points

Extension point	Mechanism	Where
Custom context logic	Pass your own `ContextManager` subclass/instance to `PromptEngine(context_manager=...)`	`api/prompt_engine`
Extra guardrails	Pass `extra_guardrails=[Guardrail(...), ...]` to `PromptEngine` or directly to `GuardrailEngine`	`api/guardrails`
New reasoning strategy	Subclass `BaseStrategy`, implement `_build_system`/`_build_user`, register it in `STRATEGY_REGISTRY`	`api/strategies`
Event hooks	`engine.on("prompt.built", callback)` — currently the only event name fired in the source is `"prompt.built"`	`api/prompt_engine`
External memory/cache/router	Constructor params `memory_store`, `cache_store`, `router` are stored on `PromptEngine` but not referenced anywhere else in the provided source — they appear to be integration handles reserved for external wiring	`api/prompt_engine`

[!WARNING] Unused integration handles memory_store, cache_store, and router are accepted and stored by PromptEngine.__init__, but no method in prompt_engine reads them. Documenting them as functional would be speculative; treat them as forward-declared extension slots until their consumers appear in the codebase.

Initialization order

PromptEngine.__init__ builds a GuardrailEngine (using guardrail_engine if given, else a new one seeded with extra_guardrails).
It builds a PromptBuilder, passing in context_manager (or a new ContextManager()) and the guardrail engine.
State containers are initialized: _metrics (PromptMetrics), _cache (dict), _feedback (list), _hooks (defaultdict(list)), _trace_log (list).
No I/O, network calls, or file reads happen during construction — everything is in-memory.