---
phase: 05-multi-model-discussions
plan: 01
subsystem: api
tags: [sqlalchemy, async, services, crud]

# Dependency graph
requires:
  - phase: 04-single-model-qa
    provides: AI client abstraction
  - phase: 01-foundation
    provides: SQLAlchemy models
provides:
  - Discussion CRUD operations (create, get, list, complete)
  - Round management (create, get current)
  - Message management (create, list)
affects: [05-02 open mode, 05-03 discuss mode, 05-04 mentions, 06-consensus]

# Tech tracking
tech-stack:
  added: []
  patterns: [selectinload for eager loading, async context manager for sessions]

key-files:
  created: [src/moai/core/services/discussion.py]
  modified: [src/moai/core/services/__init__.py]

key-decisions:
  - "selectinload for rounds→messages to prevent N+1 queries"
  - "Eager load consensus relationship in get_discussion"

patterns-established:
  - "Discussion service pattern matching project.py"
  - "get_current_round returns highest round_number"

issues-created: []

# Metrics
duration: 2min
completed: 2026-01-16
---

# Phase 5 Plan 1: Discussion Service Summary

**Discussion service with 9 async CRUD operations for discussions, rounds, and messages using selectinload eager loading**

## Performance

- **Duration:** 2 min
- **Started:** 2026-01-16T19:24:14Z
- **Completed:** 2026-01-16T19:26:56Z
- **Tasks:** 2
- **Files modified:** 2

## Accomplishments

- Created discussion service following established service layer pattern
- Implemented 5 discussion operations: create, get (with eager loading), get_active, list, complete
- Added 4 round/message operations: create_round, get_current_round, create_message, get_round_messages
- Used selectinload for eager loading rounds→messages to avoid N+1 queries

## Task Commits

Each task was committed atomically:

1. **Task 1: Create discussion service with CRUD operations** - `3258c3a` (feat)
2. **Task 2: Add round and message operations** - `baf02bb` (feat)

## Files Created/Modified

- `src/moai/core/services/discussion.py` - Discussion, Round, Message CRUD operations (9 async functions)
- `src/moai/core/services/__init__.py` - Updated exports

## Decisions Made

- Used selectinload for eager loading rounds→messages→consensus to prevent N+1 queries
- get_discussion includes consensus in eager loading for future phase 6
- get_current_round orders by round_number desc with limit 1 for efficiency

## Deviations from Plan

None - plan executed exactly as written.

## Issues Encountered

None

## Next Phase Readiness

- Discussion service ready for /open and /discuss command handlers
- Round/message operations available for multi-model discussion flow
- Ready for 05-02-PLAN.md (open mode handler)

---
*Phase: 05-multi-model-discussions*
*Completed: 2026-01-16*