# Implementation Plan: Configurable Belief State Logging

**Branch**: `006-configurable-belief-logs` | **Date**: 2025-12-26 | **Spec**: specs/006-configurable-belief-logs/spec.md
**Input**: Feature specification from `/specs/006-configurable-belief-logs/spec.md`

**Note**: This template is filled in by the `/speckit.plan` command. See `.specify/templates/commands/plan.md` for the execution workflow.

## Summary

Implement a configurable logging system with "Belief State" support (Entry, Action, Coherence, Exit).
Approach: Use Python's `logging` module with a custom Context Manager (`belief_scope`) and extend `GlobalSettings` with a `LoggingConfig` model.

## Technical Context

**Language/Version**: Python 3.9+
**Primary Dependencies**: FastAPI (Backend), Pydantic (Config), Svelte (Frontend)
**Storage**: Filesystem (for log files), JSON (for configuration persistence)
**Testing**: pytest (Backend), manual verification (Frontend)
**Target Platform**: Linux server (primary), cross-platform compatible
**Project Type**: Web application (Backend + Frontend)
**Performance Goals**: Low overhead logging (<1ms per log entry), non-blocking for main thread (mostly)
**Constraints**: Must use standard library `logging` where possible; Log rotation to prevent disk overflow
**Scale/Scope**: Configurable log levels and retention policies

## Constitution Check

*GATE: Must pass before Phase 0 research. Re-check after Phase 1 design.*

- **Library-First**: N/A (Core infrastructure)
- **CLI Interface**: N/A (Configured via UI/API/JSON)
- **Test-First**: Will require unit tests for `belief_scope` and config updates.
- **Integration Testing**: Will require testing the settings API.
- **Observability**: This feature *is* the observability enhancement.

## Project Structure

### Documentation (this feature)

```text
specs/[###-feature]/
├── plan.md              # This file (/speckit.plan command output)
├── research.md          # Phase 0 output (/speckit.plan command)
├── data-model.md        # Phase 1 output (/speckit.plan command)
├── quickstart.md        # Phase 1 output (/speckit.plan command)
├── contracts/           # Phase 1 output (/speckit.plan command)
└── tasks.md             # Phase 2 output (/speckit.tasks command - NOT created by /speckit.plan)
```

### Source Code (repository root)

```text
backend/
├── src/
│   ├── core/
│   │   ├── config_models.py       # Add LoggingConfig
│   │   ├── config_manager.py      # Update config loading/saving
│   │   └── logger.py              # Add belief_scope and configure_logger
│   └── api/
│       └── routes/
│           └── settings.py        # Update GlobalSettings endpoint
└── tests/
    └── test_logger.py             # New tests for logger logic

frontend/
├── src/
│   ├── pages/
│   │   └── Settings.svelte        # Add logging UI controls
│   └── lib/
│       └── api.js                 # Update API calls if needed
```

**Structure Decision**: enhancing existing Backend/Frontend structure.

## Complexity Tracking

> **Fill ONLY if Constitution Check has violations that must be justified**

| Violation | Why Needed | Simpler Alternative Rejected Because |
|-----------|------------|-------------------------------------|
| [e.g., 4th project] | [current need] | [why 3 projects insufficient] |
| [e.g., Repository pattern] | [specific problem] | [why direct DB access insufficient] |