docs(04-01): complete AI client abstraction plan

- Add 04-01-SUMMARY.md with plan completion details
- Update STATE.md with Phase 4 progress and decisions
- Update ROADMAP.md with plan count and status

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.planning/ROADMAP.md

@@ -50,7 +50,7 @@ None
 **Depends on**: Phase 3
 **Research**: Likely (external AI API integration)
 **Research topics**: Requesty API documentation, OpenRouter API, async HTTP patterns with httpx/aiohttp
-**Plans**: TBD
+**Plans**: 3 (04-01 AI client, 04-02 /ask command, 04-03 error handling)
 
 ### Phase 5: Multi-Model Discussions
 **Goal**: Open mode (parallel), discuss mode (sequential rounds), and @mention direct messages
@@ -74,6 +74,6 @@ Phases execute in numeric order: 1 → 2 → 3 → 4 → 5 → 6
 | 1. Foundation | 3/3 | Complete | 2026-01-16 |
 | 2. Bot Core | 2/2 | Complete | 2026-01-16 |
 | 3. Project CRUD | 3/3 | Complete | 2026-01-16 |
-| 4. Single Model Q&A | 0/TBD | Not started | - |
+| 4. Single Model Q&A | 1/3 | In progress | - |
 | 5. Multi-Model Discussions | 0/TBD | Not started | - |
 | 6. Consensus & Export | 0/TBD | Not started | - |

.planning/STATE.md

@@ -5,23 +5,23 @@
 See: .planning/PROJECT.md (updated 2026-01-16)
 
 **Core value:** Get richer, more diverse AI insights through structured multi-model discussions—ask a team of AIs instead of just one.
-**Current focus:** Phase 3 — Project CRUD (complete)
+**Current focus:** Phase 4 — Single Model Q&A (in progress)
 
 ## Current Position
 
-Phase: 3 of 6 (Project CRUD)
+Phase: 4 of 6 (Single Model Q&A)
-Plan: 3 of 3 in current phase
+Plan: 1 of 3 in current phase
-Status: Phase complete
+Status: In progress
-Last activity: 2026-01-16 — Completed 03-03-PLAN.md (project models/delete)
+Last activity: 2026-01-16 — Completed 04-01-PLAN.md (AI client abstraction)
 
-Progress: █████░░░░░ ~50%
+Progress: █████▓░░░░ ~55%
 
 ## Performance Metrics
 
 **Velocity:**
-- Total plans completed: 8
+- Total plans completed: 9
 - Average duration: 4 min
-- Total execution time: 0.5 hours
+- Total execution time: 0.6 hours
 
 **By Phase:**
 
@@ -30,9 +30,10 @@ Progress: █████░░░░░ ~50%
 | 01-foundation | 3 | 15 min | 5 min |
 | 02-bot-core | 2 | 4 min | 2 min |
 | 03-project-crud | 3 | 11 min | 4 min |
+| 04-single-model-qa | 1 | 5 min | 5 min |
 
 **Recent Trend:**
-- Last 5 plans: 02-02 (2 min), 03-01 (3 min), 03-02 (3 min), 03-03 (5 min)
+- Last 5 plans: 03-01 (3 min), 03-02 (3 min), 03-03 (5 min), 04-01 (5 min)
 - Trend: Fast
 
 ## Accumulated Context
@@ -58,6 +59,8 @@ Recent decisions affecting current work:
 - **03-02:** user_data dict for storing selected_project_id
 - **03-03:** Explicit project ID required for delete (safety)
 - **03-03:** Comma-separated model list parsing
+- **04-01:** OpenAI SDK for router abstraction (Requesty/OpenRouter compatible)
+- **04-01:** Module-level singleton for AI client (matches database pattern)
 
 ### Deferred Issues
 
@@ -69,6 +72,6 @@ None yet.
 
 ## Session Continuity
 
-Last session: 2026-01-16T18:55:00Z
+Last session: 2026-01-16T19:05:00Z
-Stopped at: Completed 03-03-PLAN.md (project models/delete) - Phase 3 complete
+Stopped at: Completed 04-01-PLAN.md (AI client abstraction)
 Resume file: None

.planning/phases/04-single-model-qa/04-01-SUMMARY.md

@@ -0,0 +1,95 @@
+---
+phase: 04-single-model-qa
+plan: 01
+subsystem: api
+tags: [openai, ai-client, requesty, openrouter, async]
+
+# Dependency graph
+requires:
+  - phase: 03-project-crud
+    provides: BotConfig pattern, project context
+provides:
+  - AIClient class for AI model interactions
+  - MODEL_MAP with claude/gpt/gemini short names
+  - Module-level init_ai_client/get_ai_client functions
+  - Config extended with AI router settings
+affects: [04-02, 04-03, 05-multi-model, discussion handlers]
+
+# Tech tracking
+tech-stack:
+  added: [openai]
+  patterns: [async-client-singleton, model-routing-abstraction]
+
+key-files:
+  created: [src/moai/core/ai_client.py]
+  modified: [pyproject.toml, src/moai/bot/config.py]
+
+key-decisions:
+  - "OpenAI SDK for router abstraction (both Requesty and OpenRouter are OpenAI-compatible)"
+  - "Module-level singleton pattern for AI client (matches database pattern)"
+  - "Short model names (claude/gpt/gemini) mapped to full identifiers"
+
+patterns-established:
+  - "AI client abstraction: all AI calls go through AIClient.complete()"
+  - "Model name resolution: short names in code, full identifiers to routers"
+
+issues-created: []
+
+# Metrics
+duration: 5min
+completed: 2026-01-16
+---
+
+# Phase 04-01: AI Client Abstraction Summary
+
+**OpenAI SDK-based AI client with Requesty/OpenRouter routing and claude/gpt/gemini model mappings**
+
+## Performance
+
+- **Duration:** 5 min
+- **Started:** 2026-01-16T19:00:00Z
+- **Completed:** 2026-01-16T19:05:00Z
+- **Tasks:** 2
+- **Files modified:** 3
+
+## Accomplishments
+- Created AIClient class wrapping AsyncOpenAI for model routing
+- Extended BotConfig with ai_router, ai_api_key, ai_referer settings
+- Added MODEL_MAP with claude, gpt, gemini short name mappings
+- Implemented module-level singleton pattern with init_ai_client/get_ai_client
+
+## Task Commits
+
+Each task was committed atomically:
+
+1. **Task 1: Add openai dependency and extend config** - `3740691` (feat)
+2. **Task 2: Create AI client abstraction** - `e04ce4e` (feat)
+
+**Plan metadata:** `f8fa4e7` (docs)
+
+## Files Created/Modified
+- `src/moai/core/ai_client.py` - AIClient class, MODEL_MAP, init/get functions
+- `pyproject.toml` - Added openai dependency
+- `src/moai/bot/config.py` - Extended BotConfig with AI settings
+
+## Decisions Made
+- Used OpenAI SDK instead of raw httpx - both Requesty and OpenRouter are OpenAI-compatible
+- Default router is "requesty" (can be changed via AI_ROUTER env var)
+- Model short names (claude/gpt/gemini) resolve to specific model versions
+
+## Deviations from Plan
+
+None - plan executed exactly as written.
+
+## Issues Encountered
+
+None.
+
+## Next Phase Readiness
+- AI client foundation ready for /ask command implementation in 04-02
+- Model routing abstraction enables easy addition of new models
+- Singleton pattern allows handlers to access client via get_ai_client()
+
+---
+*Phase: 04-single-model-qa*
+*Completed: 2026-01-16*