nexus/.planning/phases/21-chat-foundation/21-01-SUMMARY.md

phase	plan	subsystem	tags	dependency_graph	tech_stack	key_files	decisions	metrics
21-chat-foundation	01	chat-api	db-schema rest-api drizzle service-layer tdd	requires provides affects chat_conversations Drizzle table and migration chat_messages Drizzle table and migration ChatConversation and ChatMessage TypeScript interfaces createConversationSchema, updateConversationSchema, createMessageSchema Zod validators chatService factory with full CRUD chatRoutes factory with 11 REST endpoints packages/db (new schema tables) packages/shared (new types + validators) server (new service + routes + app mounting)	added patterns Drizzle ORM schema for chat_conversations and chat_messages Factory function service pattern (chatService(db)) Factory function route pattern (chatRoutes(db)) Cursor-based pagination (updatedAt DESC) Auto-title on first message (idempotent WHERE title IS NULL)	created modified packages/db/src/schema/chat_conversations.ts packages/db/src/schema/chat_messages.ts packages/db/src/migrations/0047_fixed_johnny_storm.sql packages/shared/src/types/chat.ts packages/shared/src/validators/chat.ts server/src/services/chat.ts server/src/routes/chat.ts server/src/__tests__/chat-service.test.ts server/src/__tests__/chat-routes.test.ts packages/db/src/schema/index.ts packages/shared/src/index.ts packages/shared/src/types/index.ts packages/shared/src/validators/index.ts server/src/routes/index.ts server/src/app.ts	Used isNull(chatConversations.title) with AND condition for idempotent title-setting on first message listConversations fetches limit+1 to determine hasMore without extra COUNT query addMessage reads conversation after insert to check title IS NULL — keeps update idempotent	duration_minutes completed_date tasks_completed files_created files_modified 4 2026-04-01 2 9 6

Phase 21 Plan 01: Chat Foundation — DB Schema, Types, Service, Routes Summary

One-liner: PostgreSQL chat schema with Drizzle ORM, Zod validators, cursor-paginated service, and 11-endpoint REST API — all TDD, 24 tests passing.

What Was Built

Two new Drizzle schema tables (chat_conversations, chat_messages) with a generated migration (0047), shared TypeScript interfaces and Zod validators in @paperclipai/shared, a chatService factory with full CRUD including auto-title on first message and cursor-based pagination, and chatRoutes factory with 11 REST endpoints mounted in app.ts.

Tasks Completed

Task	Description	Commit
1	DB schema, shared types, validators, service + service tests	0152d958
2	REST API routes and route tests	22547a9c

Test Results

• chat-service.test.ts: 12 tests, all passing
• chat-routes.test.ts: 12 tests, all passing
• Total: 24 tests, 0 failures

API Endpoints

Method	Path	Description
GET	/api/companies/:companyId/conversations	List conversations (cursor paginated)
POST	/api/companies/:companyId/conversations	Create conversation
GET	/api/conversations/:id	Get conversation
PATCH	/api/conversations/:id	Update conversation title
DELETE	/api/conversations/:id	Soft delete conversation
POST	/api/conversations/:id/archive	Archive conversation
POST	/api/conversations/:id/unarchive	Unarchive conversation
POST	/api/conversations/:id/pin	Pin conversation
POST	/api/conversations/:id/unpin	Unpin conversation
GET	/api/conversations/:id/messages	List messages (cursor paginated)
POST	/api/conversations/:id/messages	Add message (auto-sets title if null)

Deviations from Plan

None — plan executed exactly as written.

Known Stubs

None — all service methods are fully implemented with real Drizzle ORM calls.

Self-Check: PASSED

• All 8 created files found on disk
• Commits 0152d958 and 22547a9c verified in git log