---
phase: 16-multi-user-data-model
plan: 03
subsystem: api
tags: [hono, mcp, userId, multi-user, routes, middleware]

# Dependency graph
requires:
  - phase: 16-01
    provides: "Schema with userId columns, auth middleware setting c.set('userId')"
  - phase: 16-02
    provides: "Service functions accepting userId as second parameter"
provides:
  - "All route handlers extract userId from context and pass to services"
  - "Settings routes use composite PK [userId, key] for per-user settings"
  - "MCP server creation receives userId, all tool registrations pass userId"
  - "MCP auth middleware resolves userId from API key and Bearer token"
affects: [16-04, tests, e2e]

# Tech tracking
tech-stack:
  added: []
  patterns: ["userId extraction pattern: const userId = c.get('userId')!", "MCP session stores userId alongside transport"]

key-files:
  created: []
  modified:
    - src/server/routes/items.ts
    - src/server/routes/categories.ts
    - src/server/routes/threads.ts
    - src/server/routes/setups.ts
    - src/server/routes/settings.ts
    - src/server/routes/totals.ts
    - src/server/routes/auth.ts
    - src/server/mcp/index.ts
    - src/server/mcp/tools/items.ts
    - src/server/mcp/tools/categories.ts
    - src/server/mcp/tools/threads.ts
    - src/server/mcp/tools/setups.ts
    - src/server/mcp/resources/collection.ts

key-decisions:
  - "Used non-null assertion (!) on c.get('userId') since requireAuth middleware guarantees it"
  - "Stored userId alongside transport in MCP session map for session reuse"
  - "Images route left unchanged -- image uploads have no user-scoped DB operations"

patterns-established:
  - "Route handler pattern: const userId = c.get('userId')! after const db = c.get('db')"
  - "MCP tool registration pattern: registerXTools(db, userId) with userId closure"
  - "Settings composite key: [settings.userId, settings.key] for onConflictDoUpdate target"

requirements-completed: [MULTI-02, MULTI-05, MULTI-06]

# Metrics
duration: 6min
completed: 2026-04-05
---

# Phase 16 Plan 03: Route and MCP userId Wiring Summary

**Complete userId propagation chain from auth middleware through routes and MCP tools to service layer**

## Performance

- **Duration:** 6 min
- **Started:** 2026-04-05T08:46:34Z
- **Completed:** 2026-04-05T08:52:52Z
- **Tasks:** 2
- **Files modified:** 13

## Accomplishments
- All 36 route handler calls now extract userId from Hono context and pass to service functions
- Settings routes use composite primary key [userId, key] for per-user settings isolation
- MCP server creation receives userId, all 4 tool registration functions and collection summary pass userId
- MCP auth middleware resolves userId from both API key and Bearer token authentication

## Task Commits

Each task was committed atomically:

1. **Task 1: Update all route handlers to extract and pass userId** - `e780022` (feat)
2. **Task 2: Update MCP server and tool registrations with userId** - `d4bf4f5` (feat)

## Files Created/Modified
- `src/server/routes/items.ts` - Added userId extraction to all 8 handlers (CRUD + export/import/duplicate)
- `src/server/routes/categories.ts` - Added userId extraction to all 4 handlers
- `src/server/routes/threads.ts` - Added userId extraction to all 10 handlers (threads + candidates + reorder + resolve)
- `src/server/routes/setups.ts` - Added userId extraction to all 8 handlers (CRUD + items sync/classification/remove)
- `src/server/routes/settings.ts` - Added userId with composite key [userId, key] for reads and upserts
- `src/server/routes/totals.ts` - Added userId extraction to totals handler
- `src/server/routes/auth.ts` - Added userId extraction to API key management handlers
- `src/server/mcp/index.ts` - Updated createMcpServer(db, userId), MCP auth resolves userId, session map stores userId
- `src/server/mcp/tools/items.ts` - registerItemTools(db, userId) passes userId to all service calls
- `src/server/mcp/tools/categories.ts` - registerCategoryTools(db, userId) passes userId to all service calls
- `src/server/mcp/tools/threads.ts` - registerThreadTools(db, userId) passes userId to all service calls
- `src/server/mcp/tools/setups.ts` - registerSetupTools(db, userId) passes userId to all service calls
- `src/server/mcp/resources/collection.ts` - getCollectionSummary(db, userId) passes userId to all queries

## Decisions Made
- Used non-null assertion (`!`) on `c.get("userId")` since `requireAuth` middleware guarantees userId is set for all data routes
- Stored userId alongside transport in MCP session map to support session reuse without re-creating MCP server
- Left images route unchanged since image upload/fetch operations have no user-scoped database queries

## Deviations from Plan

None - plan executed exactly as written.

## Issues Encountered
None

## User Setup Required
None - no external service configuration required.

## Next Phase Readiness
- Complete userId propagation chain is in place: middleware -> routes/MCP -> services -> database
- Ready for Plan 04 (test updates) to verify the multi-user data isolation

## Self-Check: PASSED

All files verified present, all commits verified in history.

---
*Phase: 16-multi-user-data-model*
*Completed: 2026-04-05*