# Internal Component Overview

## Purpose

This document inventories Promptkit's implemented components for contributors.
The [architecture policy](../policy/architecture.md) owns durable boundary and
dependency rules. See the [development guide](../development.md) for
contributor workflow and validation.

## Implemented Components

| Component | Implemented responsibility | References |
| --- | --- | --- |
| Root `promptkit` package | Provides the supported engine facade, source and injection options, public request and result values, built-in profile construction, extension interfaces, value conversion, redacted formatting, and public error mapping. | [Package GoDoc](../../doc.go), [engine assembly](../../engine.go) |
| `internal/domain` | Defines internal framework values for requests, artifacts, prompt definitions, profiles, execution targets, rendering, generation, and validation. | [Domain declarations](../../internal/domain/domain.go) |
| `internal/defaults` | Defines application-neutral framework constants and constructs the default execution target. It contains no CLI, server, or inbound HTTP limits. | [Framework defaults](../../internal/defaults/defaults.go) |
| `internal/filecatalog` | Provides deterministic YAML discovery and path helpers for operating-system filesystems and `fs.FS` sources. | [File catalog](../../internal/filecatalog/catalog.go) |
| `internal/promptdef` | Loads strictly decoded, validated prompt definitions from filesystem and `fs.FS` sources, including version selection and contained file-backed message content. | [Prompt-definition repository](../../internal/promptdef/filesystem_repository.go) |
| `internal/profile` | Loads strictly decoded, validated execution profiles from filesystem and `fs.FS` sources and composes repositories with error-preserving fallback. | [Profile repositories](../../internal/profile/filesystem_repository.go) |
| `internal/profile/builtin` | Embeds the built-in execution profile catalog and combines it with an optional primary repository. | [Built-in profile repository](../../internal/profile/builtin/repository.go) |
| `internal/prompt` | Renders prompt messages from Go templates with artifact, variable, session, and cache-control data. | [Go-template renderer](../../internal/prompt/go_renderer.go) |
| `internal/artifact` | Resolves ordinary inline and unrestricted caller-selected file references into copied artifacts with metadata and hashes. | [Internal sources and validation](sources.md) |
| `internal/validate` | Validates basic, JSON, and JSON Schema output using operating-system filesystem or `fs.FS` schema sources. | [Internal sources and validation](sources.md) |
| `internal/llm` | Defines the internal generation boundary and implements outbound OpenAI-compatible chat requests, response decoding, authentication, and deadline handling. | [Internal model client](llm.md) |
| `internal/usecase` | Coordinates preparation and execution across internal sources, rendering, artifact loading, generation, validation, and optional repair. | [Internal runner](runner.md) |

The root package assembles these internal components without exposing their
representations. Consumers depend only on the root facade.

## Maintenance

Update this inventory as framework extraction introduces packages or changes
component responsibilities. List only implemented components; proposed package
boundaries belong in temporary planning documents until their implementation
lands.