docs(19-01): complete backend API for agent questions plan

Tasks completed: 2/2
- Add getAgentQuestions and listWaitingAgents tRPC procedures
- Export PendingQuestions and QuestionItem types from shared package

SUMMARY: .planning/phases/19-agent-inbox/19-01-SUMMARY.md

.planning/phases/19-agent-inbox/19-01-SUMMARY.md

@@ -0,0 +1,88 @@
+---
+phase: 19-agent-inbox
+plan: 01
+subsystem: api
+tags: [trpc, agent-questions, shared-types]
+
+# Dependency graph
+requires:
+  - phase: 18-initiative-detail
+    provides: Frontend scaffold and tRPC client wiring
+provides:
+  - getAgentQuestions tRPC procedure for structured question data
+  - listWaitingAgents tRPC procedure for inbox filtering
+  - PendingQuestions/QuestionItem shared types for frontend
+affects: [19-02-inbox-list, 19-03-question-form, 19-04-inbox-page]
+
+# Tech tracking
+tech-stack:
+  added: []
+  patterns: []
+
+key-files:
+  created: []
+  modified:
+    - src/trpc/router.ts
+    - packages/shared/src/types.ts
+    - packages/shared/src/index.ts
+
+key-decisions:
+  - "Re-export from agent/types.ts (rootDir=../.. allows cross-package import)"
+  - "listWaitingAgents filters in-memory via agentManager.list() (no new DB query needed)"
+
+# Metrics
+duration: 3min
+completed: 2026-02-04
+---
+
+# Phase 19 Plan 01: Backend API for Agent Questions Summary
+
+**Two tRPC procedures (getAgentQuestions, listWaitingAgents) and shared PendingQuestions/QuestionItem type exports for frontend inbox**
+
+## Performance
+
+- **Duration:** 3 min
+- **Started:** 2026-02-04
+- **Completed:** 2026-02-04
+- **Tasks:** 2
+- **Files modified:** 3
+
+## Accomplishments
+- Added `getAgentQuestions` procedure exposing structured question data from AgentManager
+- Added `listWaitingAgents` procedure filtering to `waiting_for_input` status
+- Exported `PendingQuestions` and `QuestionItem` types from `@codewalk-district/shared`
+
+## Task Commits
+
+Each task was committed atomically:
+
+1. **Task 1: Add getAgentQuestions and listWaitingAgents tRPC procedures** - `004140e` (feat)
+2. **Task 2: Export PendingQuestions and QuestionItem from shared package** - `47a2bb3` (feat)
+
+## Files Created/Modified
+- `src/trpc/router.ts` - Added getAgentQuestions and listWaitingAgents procedures, updated JSDoc
+- `packages/shared/src/types.ts` - Re-export PendingQuestions and QuestionItem from agent types
+- `packages/shared/src/index.ts` - Added PendingQuestions and QuestionItem to public exports
+
+## Decisions Made
+- Re-export from `../../../src/agent/types.js` works because shared tsconfig has `rootDir: "../.."`
+- `listWaitingAgents` filters `agentManager.list()` in-memory rather than adding a new DB query (agents are in-memory anyway)
+
+## Deviations from Plan
+
+None - plan executed exactly as written.
+
+## Issues Encountered
+None
+
+## User Setup Required
+None - no external service configuration required.
+
+## Next Phase Readiness
+- Both procedures available for frontend consumption via tRPC client
+- Shared types ready for import in inbox components
+- Ready for 19-02-PLAN.md (InboxList & MessageCard Components)
+
+---
+*Phase: 19-agent-inbox*
+*Completed: 2026-02-04*