nexus/.planning/phases/22-agent-streaming/22-05-SUMMARY.md

phase	plan	subsystem	tags	dependency_graph	tech_stack	key_files	decisions	metrics	requirements
22-agent-streaming	05	chat-integration	virtualization streaming chat slash-commands mentions edit-retry	requires provides affects 22-01 22-02 22-03 22-04 virtualized-message-list fully-wired-chat-panel chat-input-with-popovers chat-api-edit-truncate ui/src/components/ChatMessageList.tsx ui/src/components/ChatPanel.tsx ui/src/components/ChatInput.tsx ui/src/api/chat.ts ui/src/components/ChatMessageList.test.tsx packages/shared/src/index.ts	added patterns useVirtualizer from @tanstack/react-virtual with estimateSize: 80, overscan: 5 Dynamic height measurement via measureElement ref callback Synthetic streaming entry appended to virtualizer list with id: __streaming__ virtualizer.measure() called on streamingContent change for growing message re-measurement Slash command popover triggered by / at start of input @mention popover triggered by /@word pattern match at end of input resolveAgentFromContent routes slash > @mention > active agent handleRetry looks up actual prior user message (not hardcoded text)	created modified ui/src/components/ChatMessageList.tsx ui/src/components/ChatPanel.tsx ui/src/components/ChatInput.tsx ui/src/api/chat.ts ui/src/components/ChatMessageList.test.tsx packages/shared/src/index.ts	virtualizer.measure() called on streamingContent change to handle dynamically growing streaming message height (Pitfall 3 from RESEARCH.md) Slash command popover takes priority over mention popover — only one active at a time handleRetry truncates from the user message (not the assistant message) — this removes both the assistant message and any messages after it postMessageAndStream and savePartialMessage added to chatApi — these were specified in 22-01 plan but missing from the implemented chat.ts	duration completed tasks files ~20 minutes 2026-04-01 3 6	PERF-03 CHAT-01 CHAT-08 CHAT-10 CHAT-11 CHAT-12 INPUT-05 INPUT-06 PERF-02

Phase 22 Plan 05: Final Integration — Virtualized List, ChatPanel, ChatInput Summary

One-liner: Virtualized ChatMessageList with @tanstack/react-virtual, fully-wired ChatPanel integrating all Phase 22 components, and ChatInput with slash command and @mention popovers.

Tasks Completed

Task	Name	Commit	Key Files
1	Virtualized ChatMessageList and chat API edit/truncate methods	6eca2eff	ui/src/components/ChatMessageList.tsx, ui/src/api/chat.ts, ui/src/components/ChatMessageList.test.tsx
2	Wire ChatPanel and ChatInput with all Phase 22 features	3e4e1e72	ui/src/components/ChatPanel.tsx, ui/src/components/ChatInput.tsx
3	Automated verification (human verification deferred)	—	tsc: clean, vitest: 165 pass / 25 todo

What Was Built

Task 1: Virtualized ChatMessageList + chatApi methods

ui/src/components/ChatMessageList.tsx — Full rewrite:

• useVirtualizer with estimateSize: 80, overscan: 5, dynamic measureElement ref
• Synthetic streaming entry: id: "__streaming__", isStreamingEntry: true appended when isStreaming && streamingContent
• virtualizer.measure() called on streamingContent change for dynamic height re-measurement
• Jump-to-bottom button appears when scrolled >200px from bottom
• 3 loading Skeleton placeholders (varying widths)
• Agent identity resolved from agentMap prop or streaming agent fallback props
• Props: streamingContent, isStreaming, streamingAgentName/Icon/Role, onEdit, onRetry, agentMap

ui/src/api/chat.ts — New methods:

• postMessageAndStream — POST fetch with ReadableStream, parses SSE token/done/error events (was missing; now added)
• savePartialMessage — delegates to postMessage for partial content persistence (was missing; now added)
• editMessage — PATCH /conversations/:id/messages/:msgId
• truncateMessagesAfter — DELETE /conversations/:id/messages/after/:msgId
• deleteMessage — DELETE /conversations/:id/messages/:msgId

Task 2: ChatPanel and ChatInput integration

ui/src/components/ChatPanel.tsx — Full rewrite integrating all Phase 22 components:

• useStreamingChat provides streamingContent, isStreaming, startStream, stop
• ChatAgentSelector in header with onAgentChange → updates activeAgentId local state
• ChatStopButton shown conditionally when isStreaming
• agentMap built from agents query for message identity bars
• handleEdit: editMessage + truncateMessagesAfter + startStream with edited content
• handleRetry: finds actual last user message content, truncates from that user message onward (removes assistant + all after), re-streams
• resolveAgentFromContent for agent routing from slash commands and @mentions
• ChatInput receives agents, agentsLoading, disabled, custom placeholder

ui/src/components/ChatInput.tsx — Updated with popover support:

• New props: placeholder, agents, agentsLoading
• Slash command state: slashOpen, slashQuery — triggered when input starts with /
• @mention state: mentionOpen, mentionQuery — triggered by /@word pattern at end
• handleSlashSelect: replaces input value with selected command + space
• handleMentionSelect: replaces @query with @agentName in input value
• Slash popover takes priority (only one active at a time)
• Escape key closes open popover before clearing input

Task 3: Automated Verification Results

TypeScript: tsc --noEmit — clean (no errors)

Vitest: 41 test files, 165 tests passed, 25 todos (intentional scaffolding)

Human verification deferred per execution directive (autonomous mode, no manual stops). The following 12 verification steps require browser interaction and are deferred to the next verification session:

1. CHAT-01 — streaming tokens appear word-by-word
2. PERF-02 — sub-100ms first token from echo stub
3. CHAT-12 — stop saves partial content with [stopped] suffix
4. CHAT-10 — edit message triggers regeneration
5. CHAT-11 — retry uses actual prior user message
6. CHAT-08 — agent selector routes to selected agent
7. INPUT-05 — slash command popover opens on /, routes to PM agent
8. INPUT-06 — @mention popover opens on @, routes to named agent
9. PERF-03 — virtualized list has limited DOM nodes for large conversations
10. AGENT-04 — agent name and colored icon above assistant messages
11. THEME-03 — agent colors distinguishable across all 3 themes
12. All 11 agent roles have distinct colors

Deviations from Plan

Auto-fixed Issues

1. [Rule 1 - Bug] Fixed duplicate ChatConversation type exports in packages/shared/src/index.ts

• Found during: Task 1 (pre-existing, causing TypeScript compile failure)
• Issue: ChatConversation, ChatMessage, and 3 other types were exported twice from packages/shared/src/index.ts — once at line 569 and again at line 622. This caused TS2300: Duplicate identifier errors.
• Fix: Removed the redundant second export block (lines 622-628)
• Files modified: packages/shared/src/index.ts
• Commit: 6eca2eff

2. [Rule 1 - Bug] Added missing postMessageAndStream and savePartialMessage to chatApi

• Found during: Task 1 (pre-existing — useStreamingChat.ts and useStreamingChat.test.ts both referenced these methods but they were absent from chat.ts)
• Issue: useStreamingChat.ts called chatApi.postMessageAndStream and chatApi.savePartialMessage, and the test file mocked them, but neither method existed in ui/src/api/chat.ts. The 22-01 SUMMARY stated they were added, but they were not present.
• Fix: Added both methods with correct SSE ReadableStream parsing and partial message saving
• Files modified: ui/src/api/chat.ts
• Commit: 6eca2eff

3. [Rule 3 - Blocking] Installed @testing-library/react devDependency

• Found during: Task 1 verification (tsc --noEmit)
• Issue: @testing-library/react ^16.0.0 was in ui/package.json devDependencies but not installed; useStreamingChat.test.ts imports it causing TS2307 error
• Fix: Ran pnpm install to install the declared but missing dependency
• Commit: included in 6eca2eff

Known Stubs

None affecting this plan's goal. The streamEcho stub in the server yields word-by-word with 50ms delay — this is intentional and documented (Phase 23 replaces with real LLM adapter per DECISIONS.md).

Self-Check: PASSED