Implement Phase 1: Clean Architecture foundation for canon-aware knowledge engine

[Copilot]

Bootstraps Palimpsest, a local-first authoring tool for managing large fictional universes with graph-first canon tracking, epistemic awareness, and provenance.

Architecture

Clean Architecture with strict dependency inversion:

• Domain: 13 entities, 11 enums. Zero external dependencies.
• Application: Repository/service interfaces. Defines contracts.
• Infrastructure: EF Core, PostgreSQL with pgvector/pg_trgm, stub LLM providers.
• Web: ASP.NET Core + HTMX + Shoelace. Server-rendered HTML.

Database Schema

Complete implementation per specification:

• Canon graph: entities, assertions (append-only), edges (denormalized traversal)
• Provenance: documents, document_versions, segments with stable locators
• Epistemic tracking: Observed/Believed/Inferred categories on assertions
• Review queue: questionable_items for conflicts, identity ambiguity, constraint violations
• Context: dossiers (materialized bounded entity views), jobs (async pipeline tracking)
• Vector search: segment_embeddings using pgvector for semantic retrieval

Indexes optimized for universe-scoped queries and graph traversal.

Core Concepts

Universe scoping: All operations execute within active universe boundary. Session-based context service enforces isolation.

Append-only assertions: S-P-O triples with typed objects (entity/literal/json), confidence scores, time scopes, and mandatory evidence segment references. No updates—conflicts flagged for author resolution.

Ingestion pipeline: Text → normalized → segments (chapter/section aware) → entities/mentions → assertions → edges. LLM integration stubbed for Phase 1.

Implementation

Repositories: Universe, Document, Entity, Assertion, Segment, Job. Async throughout.

Services:

• UniverseContextService: Session-based active universe tracking
• IngestionService: Text normalization, structural segmentation (chapter/section detection)
• StubLLMProvider, StubEmbeddingService: Placeholders for Ollama/OpenRouter integration

UI: Universe CRUD with active universe indicator. Shoelace web components, HTMX for interactivity.

Docker

docker-compose.yml provisions PostgreSQL with pgvector extension. EF Core migrations ready.

Example Usage

// Universe-scoped repository access
var universeId = _universeContext.RequireActiveUniverseId();
var entities = await _entityRepository.GetByUniverseIdAsync(universeId);

// Append-only assertion creation
var assertion = new Assertion
{
    SubjectEntityId = entity.EntityId,
    Predicate = "birthday_day_month",
    ObjectKind = ObjectKind.Literal,
    ObjectLiteral = "10-07",
    Epistemic = EpistemicCategory.Observed,
    EvidenceSegmentId = segment.SegmentId,
    Confidence = 0.95f
};
await _assertionRepository.CreateAsync(assertion);

Deferred to Phase 2

• Document upload UI and LLM-based extraction
• Entity browsing and mention resolution
• Conflict detection and dossier generation
• Real LLM provider integration (Ollama/OpenRouter)

Original prompt

You are a senior software engineer acting as the primary implementer of an open-source, local-first authoring tool.

PROJECT OVERVIEW

You are building “Palimpsest”: a canon-aware knowledge engine for authors managing large fictional universes across many books and timelines.

The authoritative design is defined in the repository document titled 'spec' (primary specification)

These documents are ground truth. Do not invent features that contradict them. If anything is ambiguous or underspecified, stop and ask for clarification before proceeding.

---

TECHNICAL CONSTRAINTS (NON-NEGOTIABLE)

• Language / Framework: C# on .NET (current LTS)
• Frontend: Server-rendered HTML using HTMX and Shoelace
• Database: PostgreSQL with pgvector and pg_trgm
• Deployment: Docker Compose (local-first)
• LLM Integration:
  • MVP support for local models (Ollama or equivalent)
  • Configurable support for OpenRouter
  • Provider-agnostic architecture
• Embeddings: Local embedding computation for MVP
• Authentication: Single-user, no login required (leave seams for future auth)
• Scope Isolation: Hard universe boundaries; all operations occur within an active Universe context

---

ARCHITECTURAL PRINCIPLES

You must follow these principles strictly:

1. Graph-first, not RAG-first

   • Entities, Assertions, Edges, and Conflicts are the system of record
   • Embeddings are retrieval helpers only

2. Append-only canon

   • Never overwrite assertions
   • Conflicts are flagged, not auto-resolved

3. Epistemic awareness

   • Every assertion is explicitly Observed, Believed, or Inferred

4. Provenance is mandatory

   • Every assertion must point to an evidence segment with stable locators

5. Universe as global mode

   • UI has a persistent Universe selector
   • All chat, ingestion, search, and commands operate within the active universe

6. Bounded LLM context

   • Use entity dossiers and relevant segments
   • Never attempt to feed the entire universe into an LLM prompt

---

INITIAL RESPONSIBILITIES (PHASE 1)

Start with infrastructure and spine, not UI polish.

STEP 1: Repository Initialization

• Create a clean solution structure:
  • /src/App (ASP.NET Core app)
  • /src/Domain (entities, assertions, predicates, enums)
  • /src/Infrastructure (Postgres, pgvector, repositories)
  • /src/LLM (provider interfaces and adapters)
  • /docs (do not modify specs unless explicitly instructed)
• Establish database migrations tooling

STEP 2: Database Schema
Implement the schema exactly as defined in the specification, including:

• universes
• documents / document_versions
• segments and segment_embeddings
• entities, aliases, and mentions
• assertions
• edges
• questionable_items
• dossiers
• jobs

Do not simplify the model “for now.” This schema is foundational.

STEP 3: Universe Context Plumbing

• Implement a UniverseContext abstraction
• Persist active universe selection (session or local storage)
• Enforce universe scoping at repository and query boundaries

STEP 4: Ingestion Skeleton (No LLM Yet)

• Accept .txt and .md uploads
• Store raw and normalized text
• Segment text into chapter/section/paragraph-style units
• Persist segments with stable source locators
• Create ingest jobs and progress tracking

STEP 5: Minimal Entity and Assertion Pipeline (Stubbed LLM)

• Implement entity creation
• Implement alias handling
• Implement assertion persistence
• Implement edge materialization
• Stub LLM calls initially (mock assertions)
• Ensure append-only behavior and provenance wiring

---

EXPLICITLY DEFER (DO NOT IMPLEMENT YET)

• Full chat UX
• Rich event modeling
• Canon adjudication UI
• Automated timeline solving
• Advanced derivations beyond simple constraints
• Multi-user authentication

If unsure whether something belongs in Phase 1, defer it.

---

DEVELOPMENT PROCESS EXPECTATIONS

• Work incrementally
• Prefer correctness and clarity over speed
• Add TODOs where the spec implies later work
• Write clean, readable code with explicit intent
• Favor testability, even if tests are added later

When completing a meaningful milestone, summarize:

• What was implemented
• What assumptions were made
• What is ready for review

---

MENTAL MODEL REMINDER

This system is not a chatbot with documents.
It is a canon compiler:

Documents → Segments
Segments → Assertions
Assertions → Graph
Graph → Dossiers
Dossiers → LLM grounding

If you lose this mental model, stop and realign.

Begin with schema and universe context, then proceed step by step.
Do not rush.

---

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[JDRay42]

Initial shot by Sonnet 4.5 at following spec.

[Copilot]

Pull request overview

This PR implements Phase 1 of Palimpsest, establishing the foundational Clean Architecture for a canon-aware knowledge engine designed for managing fictional universes. The implementation focuses on bootstrapping the core infrastructure, universe management, and basic UI scaffolding while deferring LLM integration and advanced features to Phase 2.

Key changes:

• Complete database schema implementation with EF Core, PostgreSQL, pgvector support
• Universe CRUD operations with session-based context service
• ASP.NET Core web application with HTMX + Shoelace UI
• Stub services for LLM and embedding providers
• Text ingestion pipeline with normalization and segmentation

Reviewed changes

Copilot reviewed 110 out of 149 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
src/Palimpsest.Web/Program.cs	Service registration, EF Core configuration, repository and service dependency injection setup
src/Palimpsest.Web/Controllers/UniversesController.cs	Universe CRUD controller with active universe context management
src/Palimpsest.Web/Views/Shared/_Layout.cshtml	Base layout with Shoelace web components and HTMX integration
src/Palimpsest.Web/Views/Universes/*.cshtml	Universe management UI (index, create views)
src/Palimpsest.Web/appsettings.json	Application configuration including database connection string
src/Palimpsest.Web/Palimpsest.Web.csproj	Web project configuration with EF Core Design tools
src/Palimpsest.Web/obj/*	Build artifacts (should not be in version control)
src/Palimpsest.Infrastructure/obj/*	Build artifacts (should not be in version control)

Files not reviewed (1)

• src/Palimpsest.Infrastructure/Data/Migrations/20251224031829_InitialCreate.Designer.cs: Language not supported

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[Copilot]

The SignalR script is included in the Create view but doesn't appear to be used. If SignalR functionality is not implemented yet, this script reference should be removed to avoid loading unnecessary dependencies.

[Copilot]

Build artifacts from the obj/ directories should not be committed to version control. These files are auto-generated during the build process and should be excluded via .gitignore. Committing these files can lead to merge conflicts and repository bloat.

[Copilot]

The database connection string contains hardcoded credentials (username: palimpsest, password: palimpsest_dev). For production or shared development environments, credentials should be managed through environment variables, user secrets, or a secure configuration provider to prevent accidental exposure of sensitive information.

[Copilot]

Frontend dependencies are loaded from CDN (Shoelace CSS/JS and HTMX). For a local-first application as described in the PR, consider bundling these assets locally to ensure the application works offline and to have better control over versions and security updates.

[Copilot]

This foreach loop implicitly filters its target sequence - consider filtering the sequence explicitly using '.Where(...)'.