feat: release v1.2.2 with multilingual memory hardening

2026-07-17 12:56:42 +02:00 · 2026-04-27 00:21:18 +08:00
parent 6603fe869d
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+# Workspace Memory Cleanup Migration Plan (v2)
+
+## Status: APPROVED (v3)
+
+## Problem Statement
+
+Audit of recent workspace memories found quality issues in pre-v1.2.1 stores:
+
+### Issue 1: Snapshot Violations (P0)
+
+| Workspace | Entry | Type |
+|-----------|-------|------|
+| opencode-record | `測試套件：1237 tests pass, 226 suites` | Test count |
+| opencode-record | `USB 同步：37 個文件（...）` | File count (Chinese) |
+| opencode-record | `pathology-playground...已完成 Phase 1-4` | Phase progress |
+| pathology-agent-reports | `Waves 1-5, 7 已完成，Wave 6 deferred` | Wave progress |
+
+**Root Cause**: These entries were created before P0c/P0d fix (08:02:32). Current code would reject them.
+
+**Risk**: Medium. Pollutes long-term memory, wastes tokens.
+
+### Issue 2: Sensitive Credentials (P0)
+
+| Workspace | Entry | Risk |
+|-----------|-------|------|
+| opencode-record | `Admin PIN 是 456123` | **High** - Raw credential |
+| Pre-cancer-atlas | `測試用戶名：shihlab，密碼：sushi` | **High** - Raw credential |
+
+**Root Cause**: No credential redaction in compaction extraction or storage normalization.
+
+**Risk**: High. Credentials sent to model in every compaction prompt.
+
+### Issue 3: Wave/Sprint Not Filtered (P0)
+
+| Pattern | Status |
+|---------|--------|
+| `Phase 1-4 已完成` | ✅ Filtered by P0c |
+| `Wave 1-5 已完成` | ❌ Not filtered |
+
+**Root Cause**: P0c filter only covers `Phase`, not `Wave/Sprint/Milestone/Task`.
+
+**Risk**: Medium. New snapshots still enter memory.
+
+### Issue 4: Duplicates (P1)
+
+| Workspace | Entry | Issue |
+|-----------|-------|-------|
+| Pre-cancer-atlas | `認證使用 Basic Auth...` x2 | Exact duplicate |
+| Pre-cancer-atlas | `IP 隱私...` x2 | Semantic duplicate |
+| Pre-cancer-atlas | `Cloud Run...` project + reference | Cross-type duplicate |
+
+**Root Cause**: `extractEntityKey()` only recognizes `opencode-agenthub`. Natural canonical dedup handles exact duplicates.
+
+**Risk**: Low. Wastes tokens but not dangerous.
+
+---
+
+## Architect Review Failures (v1, v2)
+
+### v1 Failures
+
+| Issue | Problem |
+|-------|---------|
+| Regex | `Waves` not matched, Chinese `\b` unreliable |
+| Superseded entries | Would be deleted by `enforceLongTermLimits()` |
+| Credential redaction | Was migration-gated, must be always-on |
+| Wave filter | Deferred to future, must be now |
+| Over-broad | `Upload limit is 10 files` would be flagged |
+| Rationale | Only redacted `text`, not `rationale` |
+
+### v2 Failures
+
+| Issue | Problem |
+|-------|---------|
+| File context | `upload` matches `Upload limit`, false positive |
+| Explicit check | Missing `source === "explicit"` check before marking |
+| Credential regex | `\S+` captures through Chinese comma tail |
+| Filter location | Don't filter in `getFrozenWorkspaceMemory()` |
+
+---
+
+## Proposed Solution (v3)
+
+### Architecture Principle
+
+```
+                    ┌─────────────────────────────────┐
+                    │ normalizeWorkspaceMemory()      │
+                    │                                 │
+                    │  1. ALWAYS redact credentials  │
+                    │     (not migration-gated)       │
+                    │                                 │
+                    │  2. Mark legacy snapshots as    │
+                    │     superseded (migration-gated)│
+                    │                                 │
+                    │  3. Preserve superseded entries │
+                    │     in storage, exclude from    │
+                    │     render                       │
+                    └─────────────────────────────────┘
+```
+
+### Key Design Decisions
+
+1. **Credential redaction is always-on** - runs on every normalize, independent of migration ID
+2. **Snapshot marking is migration-gated** - one-time cleanup for legacy entries
+3. **Superseded entries preserved in storage** - but excluded from render
+4. **Type restriction for snapshots** - only `project` type, avoid false positives
+5. **Wave/Sprint/Milestone filter added now** - not deferred
+
+---
+
+## Implementation
+
+### 1. Add Migration Tracking to Type
+
+```typescript
+// src/types.ts
+
+interface WorkspaceMemoryStore {
+  version: number;
+  workspace: { root: string; key: string };
+  limits: { maxRenderedChars: number; maxEntries: number };
+  entries: LongTermMemoryEntry[];
+  migrations?: string[];  // NEW: track applied migrations
+  updatedAt: string;
+}
+
+const MIGRATION_ID = "2026-04-26-p0-cleanup";
+```
+
+### 2. Snapshot Detection (Revised Regex)
+
+```typescript
+// src/workspace-memory.ts
+
+/**
+ * Detect snapshot violations in text.
+ * Only apply to 'project' type entries with source !== 'explicit'.
+ */
+function isProjectSnapshotViolation(text: string): boolean {
+  // Test/suite counts
+  if (/\d+\s+tests?\s+pass(?:ed)?/i.test(text)) return true;
+  if (/\d+\s+suites?\s+(?:pass|fail)/i.test(text)) return true;
+  
+  // File counts (Chinese/English) - require sync/completion context
+  // And must NOT be a limit/maximum statement
+  if (/\d+\s*(?:個|个)?\s*(?:files?|文件)/i.test(text)) {
+    const hasSnapshotContext = /同步|synced|uploaded|downloaded|completed|generated|created|modified|processed|完成/i.test(text);
+    const hasLimitContext = /limit|max|maximum|min|minimum|supports?|allowed|per\s+(?:batch|request|upload)/i.test(text);
+    if (hasSnapshotContext && !hasLimitContext) return true;
+  }
+  
+  // Phase/Wave/Sprint/Milestone progress
+  // English: Phase 1-4 completed, Waves 1-5 done
+  if (/(?:phases?|waves?|sprints?|milestones?|tasks?)\s*\d+(?:\s*[-–]\s*\d+)?/i.test(text)) {
+    if (/completed|done|finished|完成/i.test(text)) return true;
+  }
+  // Chinese: 已完成 Phase 1-4
+  if (/(?:已完成|完成).{0,30}(?:phases?|waves?|sprints?|milestones?|tasks?)/i.test(text)) return true;
+  
+  return false;
+}
+```
+
+### 3. Credential Redaction (Always-On)
+
+```typescript
+// src/workspace-memory.ts
+
+/**
+ * Bounded secret value pattern - stops at delimiters and Chinese punctuation.
+ * Avoids capturing through Chinese commas: 密碼：sushi，用於測試
+ */
+const SECRET_VALUE = String.raw`[^` + "`" + String.raw`'",，,\s]+`;
+
+/**
+ * Multilingual credential labels.
+ * These are used in both detection and redaction patterns.
+ */
+const PASSWORD_LABELS = /password|passwd|pwd|密碼|密码|パスワード|비밀번호|contraseña|mot de passe|passwort/i;
+const USERNAME_LABELS = /username|user name|用戶名|用户名|ユーザー名|사용자명|usuario|utilisateur|benutzer/i;
+
+/**
+ * Prefix patterns that capture label + delimiter together.
+ * This preserves the delimiter in output: 密碼：secret → 密碼：[REDACTED]
+ */
+const PASSWORD_PREFIX = String.raw`(${PASSWORD_LABELS.source}\s*(?:是|=|:|：)?\s*)`;
+const USERNAME_PREFIX = String.raw`(${USERNAME_LABELS.source}\s*(?:是|=|:|：)?\s*)`;
+
+/**
+ * Redact sensitive credentials from text.
+ * This runs on EVERY normalize, not just migration.
+ * Idempotent - [REDACTED] doesn't match patterns again.
+ * 
+ * Order matters:
+ * 1. PIN (standalone)
+ * 2. Username+password pairs (must run before standalone password)
+ * 3. Standalone password
+ */
+function redactCredentials(text: string): string {
+  let result = text;
+  
+  // 1. PIN patterns (language-neutral, supports 是, =, :, ：)
+  result = result.replace(
+    new RegExp(String.raw`\b(PIN|pin)\s*(?:是|=|:|：)?\s*[`'"]?(${SECRET_VALUE})`, 'gi'),
+    '$1 [REDACTED]'
+  );
+  
+  // 2. Username+Password pairs (multilingual)
+  // Must run BEFORE standalone password to match full pairs.
+  // 測試用戶名：xxx，密碼：yyy
+  // username: xxx, password: yyy
+  result = result.replace(
+    new RegExp(
+      String.raw`${USERNAME_PREFIX}[\`'"]?(${SECRET_VALUE})((?:，|,)\s*)${PASSWORD_PREFIX}[\`'"]?(${SECRET_VALUE})`,
+      'gi'
+    ),
+    '$1[REDACTED]$3$4[REDACTED]'
+  );
+  
+  // 3. Standalone password patterns (multilingual)
+  // Matches: password: secret, 密碼：secret, パスワード: secret, etc.
+  result = result.replace(
+    new RegExp(String.raw`${PASSWORD_PREFIX}[\`'"]?(${SECRET_VALUE})`, 'gi'),
+    '$1[REDACTED]'
+  );
+  
+  return result;
+}
+```
+
+### 4. Migration Function (One-Time)
+
+```typescript
+// src/workspace-memory.ts
+
+function runMigrationP0Cleanup(
+  store: WorkspaceMemoryStore,
+  nowIso: string
+): WorkspaceMemoryStore {
+  // Check if already run
+  if (store.migrations?.includes(MIGRATION_ID)) {
+    return store;
+  }
+  
+  const entries = store.entries.map(entry => {
+    // Skip explicit entries - user-added memories are preserved
+    if (entry.source === "explicit") {
+      return entry;
+    }
+    
+    // Skip non-project types for snapshot marking
+    // (Only project entries had snapshot pollution)
+    if (entry.type !== "project") {
+      return entry;
+    }
+    
+    // Mark legacy snapshot violations as superseded
+    if (isProjectSnapshotViolation(entry.text)) {
+      return {
+        ...entry,
+        status: "superseded" as const,
+        updatedAt: nowIso,
+      };
+    }
+    
+    return entry;
+  });
+  
+  return {
+    ...store,
+    entries,
+    migrations: [...(store.migrations || []), MIGRATION_ID],
+    updatedAt: nowIso,
+  };
+}
+```
+
+### 5. Normalize with Always-On Credential Redaction
+
+```typescript
+// src/workspace-memory.ts
+
+// Preserve existing normalization behavior
+async function normalizeWorkspaceMemory(
+  root: string,
+  store: WorkspaceMemoryStore,
+): Promise<WorkspaceMemoryStore> {
+  const nowIso = new Date().toISOString();
+  
+  // Start with existing store normalization
+  let result: WorkspaceMemoryStore = {
+    ...store,
+    workspace: { root, key: await workspaceKey(root) },
+    limits: {
+      maxRenderedChars: store.limits?.maxRenderedChars ?? LONG_TERM_LIMITS.maxRenderedChars,
+      maxEntries: store.limits?.maxEntries ?? LONG_TERM_LIMITS.maxEntries,
+    },
+    entries: Array.isArray(store.entries) ? store.entries : [],
+    updatedAt: nowIso,
+  };
+  
+  // ALWAYS-ON: Redact credentials in all entries
+  // This must run regardless of migration status
+  result.entries = result.entries.map(entry => {
+    const text = redactCredentials(entry.text);
+    const rationale = entry.rationale 
+      ? redactCredentials(entry.rationale) 
+      : undefined;
+    
+    if (text === entry.text && rationale === entry.rationale) {
+      return entry;
+    }
+    
+    return {
+      ...entry,
+      text,
+      rationale,
+      updatedAt: nowIso,
+    };
+  });
+  
+  // ONE-TIME: Mark legacy snapshots as superseded
+  result = runMigrationP0Cleanup(result, nowIso);
+  
+  // Remove superseded from active rendering
+  const activeEntries = result.entries.filter(e => e.status !== "superseded");
+  
+  // Apply dedup and limits to active entries only
+  const processed = enforceLongTermLimits(activeEntries);
+  
+  // Merge back: active entries + superseded entries (preserved in storage)
+  const superseded = result.entries.filter(e => e.status === "superseded");
+  
+  return {
+    ...result,
+    entries: [...processed, ...superseded],
+    updatedAt: nowIso,
+  };
+}
+```
+
+### 6. Extend P0c Snapshot Filter (Not Deferred)
+
+```typescript
+// src/extractors.ts
+
+// Add to isProjectSnapshotViolation() or equivalent filter
+
+// File counts - require snapshot context AND NOT limit context
+const FILE_COUNT_PATTERN = /\d+\s*(?:個|个)?\s*(?:files?|文件)/i;
+const FILE_SNAPSHOT_CONTEXT = /同步|synced|uploaded|downloaded|completed|generated|created|modified|processed|完成/i;
+const FILE_LIMIT_CONTEXT = /limit|max|maximum|min|minimum|supports?|allowed|per\s+(?:batch|request|upload)/i;
+
+if (FILE_COUNT_PATTERN.test(text)) {
+  if (FILE_SNAPSHOT_CONTEXT.test(text) && !FILE_LIMIT_CONTEXT.test(text)) {
+    return true; // snapshot violation
+  }
+}
+
+// Test/suite counts
+if (/\d+\s+tests?\s+pass(?:ed)?/i.test(text)) return true;
+if (/\d+\s+suites?\s+(?:pass|fail)/i.test(text)) return true;
+
+// Phase/Wave/Sprint/Milestone progress
+if (/(?:phases?|waves?|sprints?|milestones?|tasks?)\s*\d+(?:\s*[-–]\s*\d+)?/i.test(text)) {
+  if (/completed|done|finished|完成/i.test(text)) return true;
+}
+if (/(?:已完成|完成).{0,30}(?:phases?|waves?|sprints?|milestones?|tasks?)/i.test(text)) return true;
+```
+
+**Note**: Do NOT use bare `upload|download` as context. Use past-tense verbs or process states.
+
+---
+
+## Test Cases
+
+### Credential Redaction (Always-On)
+
+| Input | Expected Output |
+|-------|-----------------|
+| `Admin PIN 是 456123` | `Admin PIN 是 [REDACTED]` |
+| `Admin PIN = 456123` | `Admin PIN = [REDACTED]` |
+| `Admin PIN 456123` | `Admin PIN [REDACTED]` |
+| `密碼：sushi` | `密碼：[REDACTED]` |
+| `密码：sushi` | `密码：[REDACTED]` |
+| `password: abc-123!` | `password: [REDACTED]` |
+| `パスワード：secret` | `パスワード：[REDACTED]` |
+| `비밀번호: secret` | `비밀번호: [REDACTED]` |
+| `測試用戶名：shihlab，密碼：sushi` | `測試用戶名：[REDACTED]，密碼：[REDACTED]` |
+| `密碼：sushi，用於測試` | `密碼：[REDACTED]，用於測試` |
+| Credential in rationale | Redacted in both text and rationale |
+| Explicit entry with PIN | Redacted, preserved |
+| `[REDACTED]` in text | No change (idempotent) |
+
+### Snapshot Detection
+
+| Input | type | source | Is Violation? |
+|-------|------|--------|---------------|
+| `1237 tests pass, 226 suites` | project | compaction | ✅ Yes |
+| `USB 同步：37 個文件` | project | compaction | ✅ Yes |
+| `Phase 1-4 已完成` | project | compaction | ✅ Yes |
+| `Waves 1-5 已完成` | project | compaction | ✅ Yes |
+| `Upload limit is 10 files` | project | compaction | ❌ No (has "limit" context) |
+| `Project supports 5 test suites` | project | compaction | ❌ No (no pass/fail) |
+| `Phase 1-4 已完成` | project | explicit | ❌ No (explicit preserved) |
+| Snapshot text | feedback | compaction | ❌ No (only project type) |
+| Snapshot text | decision | compaction | ❌ No (only project type) |
+
+### Migration Behavior
+
+| Test | Description |
+|------|-------------|
+| Run once | Migration ID added |
+| Run twice | No duplicate ID, entries unchanged |
+| Non-project entry | Not marked superseded |
+| Project snapshot | Marked superseded |
+| Explicit project snapshot | Not marked (source check before type) |
+| Credential in snapshot | Redacted, then marked superseded |
+
+### Integration Tests
+
+| Test | Description |
+|------|-------------|
+| `saveWorkspaceMemory()` | Superseded entries preserved in JSON |
+| `updateWorkspaceMemory()` | Credential redaction runs on second normalize |
+| New entry with PIN | Redacted on save (always-on) |
+| `normalizeWorkspaceMemory()` | Preserves workspace root/key, limits, updatedAt |
+| Memory render | Superseded entries excluded via `enforceLongTermLimits()` |
+
+### Extractor Tests
+
+| Input | Expected |
+|-------|----------|
+| `Upload limit is 10 files` | NOT a snapshot violation (has "limit" context) |
+| `USB uploaded 37 files` | Snapshot violation (has "uploaded" process context) |
+| `Project supports 5 test suites` | NOT a snapshot violation (no pass/fail context) |
+| `1237 tests passed` | Snapshot violation (test count with pass) |
+
+---
+
+## Edge Cases
+
+| Case | Handling |
+|------|----------|
+| Entry is explicit + snapshot | Not marked (source check before type check) |
+| Entry has both snapshot + credential | Credential redacted, snapshot marked |
+| Entry is already superseded | Keep status, still redact credentials |
+| Migration runs twice | Skip if ID present |
+| Store has no migrations field | Create empty array |
+| `Upload limit is 10 files` | Not marked (has "limit" context) |
+| Password with punctuation `abc-123!` | Captured by bounded pattern |
+| Chinese comma after credential `密碼：sushi，用於測試` | Redact preserves `，用於測試` |
+| Simplified Chinese `密码` | Preserved as `密码：[REDACTED]` |
+
+---
+
+## Implementation Order
+
+1. Add `migrations` field to `WorkspaceMemoryStore` type
+2. Add snapshot patterns to `src/extractors.ts` (not deferred)
+3. Add `isProjectSnapshotViolation()` to `src/workspace-memory.ts`
+4. Add `redactCredentials()` to `src/workspace-memory.ts`
+5. Add `runMigrationP0Cleanup()` to `src/workspace-memory.ts`
+6. Update `normalizeWorkspaceMemory()` with always-on redaction + migration
+7. Do NOT add filtering to `getFrozenWorkspaceMemory()` - filtering happens in `enforceLongTermLimits()`
+8. Add test cases for all patterns
+
+---
+
+## What We Will NOT Do
+
+### Do NOT Add Project-Specific Entity Keys
+
+Cloud Run, Basic Auth, IP privacy — these are project-specific. Natural canonical dedup handles exact duplicates.
+
+### Do NOT Delete Superseded Entries
+
+Mark as `status: "superseded"`, preserve in storage, exclude from render.
+
+### Do NOT Gate Credential Redaction on Migration
+
+Credential redaction is always-on. Migration only marks legacy snapshots.
+
+---
+
+## Summary
+
+| Issue | Priority | Solution |
+|-------|----------|----------|
+| Sensitive credentials | P0 | Always-on redaction |
+| Snapshot violations | P0 | Migration-gated marking (project type only) |
+| Wave progress not filtered | P0 | Add to extractors.ts now |
+| Project-specific duplicates | N/A | Natural dedup |
+
+**Credential redaction runs on every normalize.**
+
+**Snapshot marking is one-time migration for legacy entries.**
+
+**Superseded entries preserved in storage, excluded from render.**
+
+**Wave/Sprint/Milestone filter added now, not deferred.**
+
+---
+
+## Multilingual Scope
+
+### Snapshot Detection: Chinese + English Only
+
+Do **not** add Japanese/Korean/Spanish/French/German snapshot regexes now.
+
+Reasons:
+- False positives silently suppress valid durable memories
+- Audit evidence only shows Chinese and English pollution
+- Words like "completed", "terminé", "abgeschlossen" can appear in durable process descriptions
+- Extraction is always-on, so every false positive becomes permanent blind spot
+
+Add languages only after seeing real polluted memories in those languages.
+
+### Credential Redaction: Add Multilingual Labels
+
+For credentials, false negatives leak secrets. Add high-signal multilingual labels now.
+
+**Password labels:**
+
+```typescript
+const PASSWORD_LABELS =
+  /password|passwd|pwd|密碼|密码|パスワード|비밀번호|contraseña|mot de passe|passwort/i;
+```
+
+**Username labels:**
+
+```typescript
+const USERNAME_LABELS =
+  /username|user name|用戶名|用户名|ユーザー名|사용자명|usuario|utilisateur|benutzer/i;
+```
+
+PIN remains language-neutral: `/\bPIN\b/i`
+
+### Memory Trigger Patterns: Add Chinese Expansion + Japanese + Korean
+
+#### Chinese Expansion
+
+Add common phrases:
+
+```typescript
+// Current: 记住/記住
+// Add: 记得/記得, 记下来/記下來
+
+/(?:^|\n)\s*(?:请|請)?(?:帮我|幫我)?(?:记住|記住|记得|記得|记下来|記下來)(?:这一点|這一點|这点|這點|这个|這個)?[:：,，]?\s*(.+)$/gim
+```
+
+#### Japanese Positive Triggers
+
+```typescript
+/(?:^|\n)\s*(?:覚えておいて|覚えて|忘れないで|メモして)[:：,，]?\s*(.+)$/gim
+```
+
+Note: `覚えておいて` must come before `覚えて` to prevent partial match in body.
+Note: `忘れないで` ("don't forget") is a positive memory request despite negative morphology.
+
+#### Japanese Negation
+
+```typescript
+/(?:覚えないで|記憶しないで|メモしないで)\s*$/u
+```
+
+#### Korean Positive Triggers
+
+```typescript
+/(?:^|\n)\s*(?:기억해줘|기억해|잊지 마|잊지마|메모해줘|메모해)[:：,，]?\s*(.+)$/gim
+```
+
+Note: `기억해줘` must come before `기억해`, `메모해줘` must come before `메모해` to prevent partial match in body.
+Note: `잊지 마` ("don't forget") is a positive memory request despite negative morphology.
+
+#### Korean Negation
+
+```typescript
+/(?:기억하지\s*마|기억하지마|메모하지\s*마|메모하지마)\s*$/u
+```
+
+#### Priority
+
+1. Chinese: `记得/記得`, `记下来/記下來` (small expansion)
+2. Japanese (full patterns + negation)
+3. Korean (full patterns + negation)
+4. Defer: Spanish/German/French (higher collision risk with normal text)
+
+### Tests Required
+
+**Credential redaction:**
+
+```text
+パスワード：secret → [REDACTED]
+비밀번호: secret → [REDACTED]
+contraseña: secret → [REDACTED]
+mot de passe: secret → [REDACTED]
+Passwort: secret → [REDACTED]
+```
+
+**Memory triggers (positive):**
+
+```text
+记得：这个项目使用 pnpm
+記下來：这个项目使用 pnpm
+覚えて: このプロジェクトは pnpm を使う
+覚えておいて: このプロジェクトは pnpm を使う
+忘れないで: このプロジェクトは pnpm を使う
+メモして: このプロジェクトは pnpm を使う
+기억해: 이 프로젝트는 pnpm을 사용한다
+기억해줘: 이 프로젝트는 pnpm을 사용한다
+잊지 마: 이 프로젝트는 pnpm을 사용한다
+메모해: 이 프로젝트는 pnpm을 사용한다
+메모해줘: 이 프로젝트는 pnpm을 사용한다
+```
+
+**Memory triggers (body extraction - must not include trigger suffix):**
+
+```text
+覚えておいて: このプロジェクトは pnpm を使う
+→ body is "このプロジェクトは pnpm を使う" (not "おいて: この...")
+
+기억해줘: 이 프로젝트는 pnpm을 사용한다
+→ body is "이 프로젝트는 pnpm을 사용한다" (not "줘: 이...")
+
+메모해줘: 이 프로젝트는 pnpm을 사용한다
+→ body is "이 프로젝트는 pnpm을 사용한다" (not "줘: 이...")
+```
+
+**Memory triggers (negation - should NOT trigger):**
+
+```text
+覚えないで 覚えて: temporary note only
+メモしないで メモして: temporary note only
+기억하지 마 기억해: temporary note only
+메모하지 마 메모해: temporary note only
+```
+
+---
+
+## Memory Quality Bar (Prompt Improvement)
+
+### Problem
+
+Current extraction accepts "facts that were mentioned" instead of "facts that will change future behavior."
+
+Examples of low-value trivia:
+- `Cloud Run revision: pre-cancer-atlas-website-00066-j8c` — transient deployment state
+- `UI 要統一風格：兩個表格都要 scrollable，約 20 rows` — local implementation detail
+- Paths observed from code/logs without stable contract
+
+### Solution: Prompt Quality Bar
+
+Add to compaction memory extraction prompt:
+
+```text
+Memory quality bar:
+Extract only durable facts that will change future behavior: user preferences, decisions with rationale, stable constraints, or hard-to-rediscover references.
+
+Do not extract trivia: transient IDs/revisions, task progress, test/file counts, bare status updates, local UI details, or facts easily rediscovered from the repo.
+
+When unsure, skip it. Fewer high-signal memories are better than many low-value ones.
+```
+
+### Example Pair (Optional)
+
+If model still stores junk, add one example:
+
+```text
+Bad: Cloud Run revision: xyz-00066
+Good: Revision xyz-00066 is the last known good deploy before the auth regression.
+```
+
+### What This Captures
+
+| Keep | Reject |
+|------|--------|
+| User preferences | Transient IDs/revisions |
+| Decisions with rationale | Task progress, test/file counts |
+| Stable constraints | Bare status updates |
+| Hard-to-rediscover references | Local UI details |
+| | Rediscoverable facts |
+
+### Why Prompt Instead of Code Filters
+
+- Context matters: "Cloud Run revision" might be useful if framed as "last known good before regression"
+- Avoid regex whack-a-mole for every trivia pattern
+- Model can judge wording and context
+- Easier to iterate on prompt than code
+
+### Code Filters (Stay Minimal)
+
+Keep only hard invariants:
+- Credentials (security)
+- Obvious snapshots (test counts, phase progress)
+
+Do NOT add new filters for deployment revisions, status updates, or UI trivia. Let prompt handle those.
+
+---
+
+## Summary