# BRIEFING — 2026-10-01T02:51:00Z

## Mission
Remediate Client Chat Security & Verification Hardening in `client/webapp/js/ui/chat_ui.js` and `tests/unit/test_webapp_chat_ui.py`.

## 🔒 My Identity
- Archetype: worker
- Roles: implementer, qa, specialist
- Working directory: c:\Projects\FreeExile\.agents\teamwork\worker_chat_m2_fix_1
- Original parent: ea9d395f-60cc-4be9-a3ac-f706d683a6cd
- Milestone: M2 Fix (Client Chat Security & Verification Hardening)

## 🔒 Key Constraints
- Exclusive file ownership: `client/webapp/js/ui/chat_ui.js` and `tests/unit/test_webapp_chat_ui.py`. Do NOT touch `server/chat/` or `tools/stress/`.
- Fix Stored XSS in `renderMessageHtml`: escape double quotes `"` and single quotes `'` as `"` and `'`.
- Fix Stored XSS in `renderChatLog`: sanitize `msg.senderName` with HTML entity escaping before inserting into `row.innerHTML`.
- Fix HMAC badge bypass: in `openItemTooltip` and link click handler, check `snapshot.isVerified === true`. If unverified/fallback, set badge to `⚠ Chưa Xác Thực` (rose red) and show `'• Không có dữ liệu thuộc tính (Chưa xác thực)'` without fake affixes. If verified, set badge to `✓ HMAC Xác Thực` (emerald green).
- Bound `snapshotCache` size (max 500 entries) to prevent memory leak.
- Maintain `chat_ui.js` strictly <= 350 lines (Soft Cap).
- All unit and e2e test suites must pass 100%.
- Strict hygiene check must pass with 0 hard cap violations.

## Current Parent
- Conversation ID: ea9d395f-60cc-4be9-a3ac-f706d683a6cd
- Updated: 2026-10-01T02:51:00Z

## Task Summary
- **What to build**: Fix XSS vulnerabilities, implement honest HMAC verification display in item tooltips, bound cache, and enhance tests.
- **Success criteria**: All tests pass, zero XSS vectors, unverified items clearly flagged with warning badge, file <= 350 lines, hygiene check passes.
- **Interface contracts**: `client/webapp/js/ui/chat_ui.js` ES module export functions.
- **Code layout**: `client/webapp/js/ui/chat_ui.js` and `tests/unit/test_webapp_chat_ui.py`.

## Key Decisions Made
- [Initial]: Adhere strictly to minimal diff principle to preserve line limits (<=350 lines).
- [Fix XSS]: Escaped `"` and `'` in `escapeHtml` and ensured `renderMessageHtml` and `renderChatLog` sanitize `msg.senderName` and item attributes to prevent attribute breakout and innerHTML injection.
- [Fix HMAC Badge]: Track authentic server verification `snapshot.isVerified === true`. Display `⚠ Chưa Xác Thực` (rose red) and `'• Không có dữ liệu thuộc tính (Chưa xác thực)'` for unverified/fallback items. Display `✓ HMAC Xác Thực` (emerald green) and authentic affixes for verified items.
- [Bound Cache]: Capped `snapshotCache` to strictly <= 500 entries using LRU/FIFO eviction.
- [Line Limits]: Both `chat_ui.js` (349 lines) and `test_webapp_chat_ui.py` (349 lines) are strictly <= 350 lines Soft Cap.

## Artifact Index
- `client/webapp/js/ui/chat_ui.js` — Client chat UI logic and DOM manipulation.
- `tests/unit/test_webapp_chat_ui.py` — Unit test suite for client chat UI.
- `c:\Projects\FreeExile\.agents\teamwork\worker_chat_m2_fix_1\progress.md` — Progress heartbeat.
- `c:\Projects\FreeExile\.agents\teamwork\worker_chat_m2_fix_1\handoff.md` — 5-component handoff report.

## Change Tracker
- **Files modified**:
  - `client/webapp/js/ui/chat_ui.js`: XSS escaping (`"`, `'`, `senderName`), genuine HMAC badge & unverified message, bounded snapshot cache, line cap <= 350.
  - `tests/unit/test_webapp_chat_ui.py`: Added tests 14-18 for security, breakout prevention, sender escaping, verified/unverified badges, bounded cache, line cap <= 350.
- **Build status**: PASS (60/60 tests pass, hygiene check pass, npm run build pass).
- **Pending issues**: None.

## Quality Status
- **Build/test result**: PASS (60/60 tests in 1.915s).
- **Lint status**: 0 Hard Cap violations, 0 Soft Cap warnings for owned files.
- **Tests added/modified**: 5 new test methods (tests 14 to 18) in `tests/unit/test_webapp_chat_ui.py`.

## Loaded Skills
- None explicitly assigned in prompt.