Data & Persistence
You MUST use this skill for ANY data persistence, database, storage, CloudKit, or serialization work.
Not on Claude Code? Where this router says "Launch some-auditor agent", read that auditor's file in this suite and follow it inline — the same procedure, needing only file search and read.
Available here: skills/codable-auditor.md, skills/core-data-auditor.md, skills/database-schema-auditor.md, skills/grdb-performance-auditor.md, skills/icloud-auditor.md, skills/storage-auditor.md, skills/swiftdata-auditor.md.
Agents that need Bash — builds, tests, simulators, crash symbolication — stay Claude Code-only; there is no inline equivalent for those.
When to Use
Use this skill when working with:
- Databases (SwiftData, Core Data, GRDB, SQLiteData)
- Schema migrations
- CloudKit sync
- File storage (iCloud Drive, local storage)
- Data serialization (Codable, JSON)
- Storage strategy decisions
- Keychain / secure credential storage
- Encryption, signing, key management (CryptoKit)
Quick Reference
| Symptom / Task |
Reference |
SwiftData @Model, @Query, ModelContext, sectioned queries / ResultsObserver / @Attribute(.codable) / dynamic compound predicates (OS27) |
See skills/swiftdata.md |
| SwiftData schema migration, VersionedSchema |
See skills/swiftdata-migration.md |
| SwiftData migration crashes, data loss |
See skills/swiftdata-migration-diag.md |
| Migrating from Realm to SwiftData |
See skills/realm-migration-ref.md |
| SwiftData vs SQLiteData decision |
See skills/sqlitedata-migration.md |
| GRDB queries, upsert, ValueObservation, DatabaseMigrator, encryption |
See skills/grdb.md |
| GRDB performance, indexes, EXPLAIN QUERY PLAN, cursors, observation not firing |
See skills/grdb-performance.md |
| Full-text search (FTS5) in GRDB or SQLiteData |
See skills/sqlite-fts-ref.md |
| Storing or querying JSON inside a SQLite column (JSON1, JSONB) |
See skills/sql-json-ref.md |
| GRDB shared across app + widget/extension (App Group) |
See skills/grdb-app-groups.md |
| SQLiteData @Table, CRUD, SyncEngine |
See skills/sqlitedata.md |
| SQLiteData advanced patterns, CTEs, views |
See skills/sqlitedata-ref.md |
@Shared / @SharedReader, appStorage or fileStorage persistence, custom SharedKey, isLoading / loadError on @FetchAll |
See skills/swift-sharing.md |
| Core Data stack, relationships, concurrency |
See skills/core-data.md |
| Core Data migration crashes, thread errors |
See skills/core-data-diag.md |
| ANY schema migration safety |
See skills/database-migration.md |
| Codable, JSON encoding/decoding |
See skills/codable.md |
| Cloud sync architecture, offline-first |
See skills/cloud-sync.md |
| CloudKit, CKSyncEngine, CKRecord |
See skills/cloudkit-ref.md |
| iCloud Drive, ubiquitous containers |
See skills/icloud-drive-ref.md |
| Cloud sync errors, conflict resolution |
See skills/cloud-sync-diag.md |
| Storage strategy, where to store data |
See skills/storage.md |
| Storage issues, files disappeared |
See skills/storage-diag.md |
| Storage management, disk pressure |
See skills/storage-management-ref.md |
| Keychain / secure credential storage |
See axiom-security (skills/keychain.md) |
| Keychain errors (errSecDuplicateItem) |
See axiom-security (skills/keychain-diag.md) |
| Keychain API reference |
See axiom-security (skills/keychain-ref.md) |
| Encryption / signing / key management |
See axiom-security (skills/cryptokit.md) |
| CryptoKit API reference |
See axiom-security (skills/cryptokit-ref.md) |
| File protection, NSFileProtection |
See axiom-security (skills/file-protection-ref.md) |
| tvOS data persistence (no guaranteed-persistent local storage) |
See axiom-swift (skills/tvos.md) |
| tvOS + CloudKit SyncEngine |
See skills/sqlitedata.md |
Automated Scanning
Core Data audit → Launch core-data-auditor agent or /axiom:audit core-data (safety violations, architectural gaps — migration options, thread-confinement, N+1 queries, merge policies, context isolation)
Codable audit → Launch codable-auditor agent or /axiom:audit codable (safety violations, semantic gaps — try? swallowing errors, JSONSerialization, date handling, silent field drops, wrapper-hidden fallbacks, cross-file strategy drift, enum future-case crashes)
iCloud audit → Launch icloud-auditor agent or /axiom:audit icloud (entitlement checks, file coordination, incomplete CKError matrix coverage, missing account-change observation, polling vs CKSubscriptions, SwiftData + CloudKit unsupported features, compound risks like uncoordinated I/O across extensions)
Storage audit → Launch storage-auditor agent or /axiom:audit storage (wrong file locations, missing backup exclusions, sensitive data on disk vs Keychain, missing App Group containers, unbounded cache growth, orphan files, compound risks like user data in tmp/ + critical content)
Database schema audit → Launch database-schema-auditor agent or /axiom:audit database-schema (unsafe ALTER TABLE, DROP operations, missing idempotency, FK constraints declared but not enforced, incomplete upgrade paths, compound risks like INSERT OR REPLACE on FK-referenced tables)
GRDB performance audit → Launch grdb-performance-auditor agent or /axiom:audit grdb-performance (raw SQL string interpolation, missing FK indexes in raw SQL, missing PRAGMA optimize for raw-GRDB apps, journal mode mismatch for app-group DBs, missing observesSuspensionNotifications for shared DBs, prefix-redundant indexes in raw SQL, legacy Record subclass, INSERT OR REPLACE misused as upsert, observation on WITHOUT ROWID tables, WITHOUT ROWID upsert bugs)
SwiftData audit → Launch swiftdata-auditor agent or /axiom:audit swiftdata (struct models, missing schema registration, array relationships without defaults, background context misuse, N+1 patterns, stale predicates, CloudKit conformance gaps, compound risks like struct model + array relationship)
Decision Tree
- SwiftData? →
skills/swiftdata.md, skills/swiftdata-migration.md
- Core Data? →
skills/core-data.md, skills/core-data-diag.md
- GRDB? →
skills/grdb.md
3a. GRDB perf, slow query, schema design for perf? → skills/grdb-performance.md
3b. FTS5 (full-text search, any layer)? → skills/sqlite-fts-ref.md
3c. DB shared across app + extension/widget/Live Activity? → skills/grdb-app-groups.md
- SQLiteData? →
skills/sqlitedata.md, skills/sqlitedata-ref.md
4a. @Shared/@SharedReader, or the loading/error state behind @FetchAll? → skills/swift-sharing.md
- ANY schema migration? →
skills/database-migration.md (ALWAYS — prevents data loss)
- Realm migration? →
skills/realm-migration-ref.md
- SwiftData vs SQLiteData? →
skills/sqlitedata-migration.md
- Cloud sync architecture? →
skills/cloud-sync.md
- CloudKit? →
skills/cloudkit-ref.md
- iCloud Drive? →
skills/icloud-drive-ref.md
- Cloud sync errors? →
skills/cloud-sync-diag.md
- Codable/JSON serialization? →
skills/codable.md
- File storage strategy? →
skills/storage.md, skills/storage-diag.md, skills/storage-management-ref.md
- File protection? → See axiom-security (skills/file-protection-ref.md)
- Keychain / storing tokens, passwords, secrets securely? → See axiom-security (skills/keychain.md), See axiom-security (skills/keychain-diag.md), See axiom-security (skills/keychain-ref.md)
- SecItem errors (errSecDuplicateItem, errSecItemNotFound, errSecInteractionNotAllowed)? → See axiom-security (skills/keychain-diag.md)
- Encryption, signing, Secure Enclave, CryptoKit? → See axiom-security (skills/cryptokit.md), See axiom-security (skills/cryptokit-ref.md)
- Quantum-secure cryptography, HPKE, ML-KEM? → See axiom-security (skills/cryptokit.md)
- Want Core Data safety scan? → core-data-auditor (Agent)
- Want Codable anti-pattern scan? → codable-auditor (Agent)
- Want iCloud sync audit? → icloud-auditor (Agent)
- Want storage location audit? → storage-auditor (Agent)
- Want database schema/migration safety scan? → database-schema-auditor (Agent)
23a. Want GRDB performance/app-group scan? → grdb-performance-auditor (Agent)
- Want SwiftData code audit? → swiftdata-auditor (Agent)
- tvOS data persistence? → See axiom-swift (skills/tvos.md) (CRITICAL: every local directory is purgeable between launches, so iCloud is the source of truth) +
skills/sqlitedata.md (CloudKit SyncEngine)
- SwiftData @MainActor / background context threading? →
/skill axiom-concurrency
- Structured data generation with Foundation Models? →
/skill axiom-ai
Sync patterns
- HealthKit anchored/observer queries as a generalizable change-tracking pattern → See axiom-health (skills/sync-and-background.md)
Anti-Rationalization
| Thought |
Reality |
| "Just adding a column, no migration needed" |
Schema changes without migration crash users. database-migration prevents data loss. |
| "I'll handle the migration manually" |
Manual migrations miss edge cases. database-migration has the safe additive patterns and both migration paths to test. |
| "Simple query, I don't need the skill" |
Query patterns prevent N+1 and thread-safety issues. The skill has copy-paste solutions. |
| "CloudKit sync is straightforward" |
CloudKit has 15+ failure modes. cloud-sync-diag diagnoses them systematically. |
| "I know Codable well enough" |
Codable has silent data loss traps (try? swallows errors). codable skill prevents production bugs. |
| "@Shared is just @AppStorage with extra steps" |
Mutation goes through $shared.withLock; the plain setter is deprecated, and below Sharing 2.8 on Swift 6.3 it is a compile error wherever a SwiftUI binding is chained into shared state. swift-sharing has the migration. |
| "I'll use local storage on tvOS" |
No local directory on tvOS is guaranteed to survive between launches — the system purges them, Caches first. See axiom-swift (skills/tvos.md) for the iCloud-first pattern. |
| "UserDefaults is fine for this token" |
UserDefaults is unencrypted, backed up to iCloud, and visible to MDM profiles. One audit catches it. keychain stores tokens securely. |
| "I'll encrypt it myself with CommonCrypto" |
CryptoKit replaced CommonCrypto's buffer-management nightmares with one-line APIs. cryptokit prevents misuse. |
Critical Pattern: Migrations
ALWAYS read skills/database-migration.md when adding/modifying database columns.
This prevents:
- "FOREIGN KEY constraint failed" errors
- "no such column" crashes
- Data loss from unsafe migrations
Example Invocations
User: "I need to add a column to my SwiftData model"
→ Read: skills/database-migration.md (critical - prevents data loss)
User: "How do I query SwiftData with complex filters?"
→ Read: skills/swiftdata.md
User: "CloudKit sync isn't working"
→ Read: skills/cloud-sync-diag.md
User: "Should I use SwiftData or SQLiteData?"
→ Read: skills/sqlitedata-migration.md
User: "How do I persist a setting to UserDefaults and observe it everywhere?"
→ Read: skills/swift-sharing.md
User: "Why is my @FetchAll empty — is it loading or did it fail?"
→ Read: skills/swift-sharing.md
User: "Check my Core Data code for safety issues"
→ Launch: core-data-auditor agent
User: "Scan for Codable anti-patterns before release"
→ Launch: codable-auditor agent
User: "Audit my iCloud sync implementation"
→ Launch: icloud-auditor agent
User: "Check if my files are stored in the right locations"
→ Launch: storage-auditor agent
User: "Audit my database migrations for safety"
→ Launch: database-schema-auditor agent
User: "How do I make my GRDB queries faster?"
→ Read: skills/grdb-performance.md
User: "Add search to my GRDB-backed app" / "Add search to SQLiteData app"
→ Read: skills/sqlite-fts-ref.md
User: "My widget needs to read the same database as the app"
→ Read: skills/grdb-app-groups.md
User: "My widget shows stale data from the database"
→ Read: skills/grdb-app-groups.md
User: "Audit my GRDB code for performance issues"
→ Launch: grdb-performance-auditor agent
User: "Check my SwiftData models for issues"
→ Launch: swiftdata-auditor agent
User: "How do I persist data on tvOS?"
→ Invoke: See axiom-swift (skills/tvos.md) + Read: skills/sqlitedata.md
User: "My tvOS app loses data between launches"
→ Invoke: See axiom-swift (skills/tvos.md)
User: "How do I store an auth token securely?"
→ Invoke: See axiom-security (skills/keychain.md)
User: "errSecDuplicateItem but I checked and the item doesn't exist"
→ Invoke: See axiom-security (skills/keychain-diag.md)
User: "How do I encrypt data with AES in Swift?"
→ Invoke: See axiom-security (skills/cryptokit.md)
User: "I need to sign data with the Secure Enclave"
→ Invoke: See axiom-security (skills/cryptokit.md)
User: "What's ML-KEM and should I use it?"
→ Invoke: See axiom-security (skills/cryptokit.md)
1---2name: axiom-data-23description: Use when working with ANY data persistence, database, storage, CloudKit, migration, or serialization in an Apple app. Covers SwiftData, Core Data, GRDB, SQLite, Realm, CloudKit sync, file storage, Codable, migrations.4license: MIT5---67# Data & Persistence89**You MUST use this skill for ANY data persistence, database, storage, CloudKit, or serialization work.**1011<!-- AXIOM_AUDITOR_INLINE_BEGIN — auto-maintained by scripts/build-inlined-auditors.ts; do not hand-edit -->12> **Not on Claude Code?** Where this router says "Launch `some-auditor` agent", read that auditor's file in this suite and follow it inline — the same procedure, needing only file search and read.13>14> Available here: `skills/codable-auditor.md`, `skills/core-data-auditor.md`, `skills/database-schema-auditor.md`, `skills/grdb-performance-auditor.md`, `skills/icloud-auditor.md`, `skills/storage-auditor.md`, `skills/swiftdata-auditor.md`.15>16> Agents that need Bash — builds, tests, simulators, crash symbolication — stay Claude Code-only; there is no inline equivalent for those.17<!-- AXIOM_AUDITOR_INLINE_END -->1819## When to Use2021Use this skill when working with:22- Databases (SwiftData, Core Data, GRDB, SQLiteData)23- Schema migrations24- CloudKit sync25- File storage (iCloud Drive, local storage)26- Data serialization (Codable, JSON)27- Storage strategy decisions28- Keychain / secure credential storage29- Encryption, signing, key management (CryptoKit)3031## Quick Reference3233| Symptom / Task | Reference |34|----------------|-----------|35| SwiftData @Model, @Query, ModelContext, sectioned queries / ResultsObserver / @Attribute(.codable) / dynamic compound predicates (`OS27`) | See `skills/swiftdata.md` |36| SwiftData schema migration, VersionedSchema | See `skills/swiftdata-migration.md` |37| SwiftData migration crashes, data loss | See `skills/swiftdata-migration-diag.md` |38| Migrating from Realm to SwiftData | See `skills/realm-migration-ref.md` |39| SwiftData vs SQLiteData decision | See `skills/sqlitedata-migration.md` |40| GRDB queries, upsert, ValueObservation, DatabaseMigrator, encryption | See `skills/grdb.md` |41| GRDB performance, indexes, EXPLAIN QUERY PLAN, cursors, observation not firing | See `skills/grdb-performance.md` |42| Full-text search (FTS5) in GRDB or SQLiteData | See `skills/sqlite-fts-ref.md` |43| Storing or querying JSON inside a SQLite column (JSON1, JSONB) | See `skills/sql-json-ref.md` |44| GRDB shared across app + widget/extension (App Group) | See `skills/grdb-app-groups.md` |45| SQLiteData @Table, CRUD, SyncEngine | See `skills/sqlitedata.md` |46| SQLiteData advanced patterns, CTEs, views | See `skills/sqlitedata-ref.md` |47| `@Shared` / `@SharedReader`, appStorage or fileStorage persistence, custom SharedKey, `isLoading` / `loadError` on `@FetchAll` | See `skills/swift-sharing.md` |48| Core Data stack, relationships, concurrency | See `skills/core-data.md` |49| Core Data migration crashes, thread errors | See `skills/core-data-diag.md` |50| ANY schema migration safety | See `skills/database-migration.md` |51| Codable, JSON encoding/decoding | See `skills/codable.md` |52| Cloud sync architecture, offline-first | See `skills/cloud-sync.md` |53| CloudKit, CKSyncEngine, CKRecord | See `skills/cloudkit-ref.md` |54| iCloud Drive, ubiquitous containers | See `skills/icloud-drive-ref.md` |55| Cloud sync errors, conflict resolution | See `skills/cloud-sync-diag.md` |56| Storage strategy, where to store data | See `skills/storage.md` |57| Storage issues, files disappeared | See `skills/storage-diag.md` |58| Storage management, disk pressure | See `skills/storage-management-ref.md` |59| Keychain / secure credential storage | See axiom-security (skills/keychain.md) |60| Keychain errors (errSecDuplicateItem) | See axiom-security (skills/keychain-diag.md) |61| Keychain API reference | See axiom-security (skills/keychain-ref.md) |62| Encryption / signing / key management | See axiom-security (skills/cryptokit.md) |63| CryptoKit API reference | See axiom-security (skills/cryptokit-ref.md) |64| File protection, NSFileProtection | See axiom-security (skills/file-protection-ref.md) |65| tvOS data persistence (no guaranteed-persistent local storage) | See axiom-swift (skills/tvos.md) |66| tvOS + CloudKit SyncEngine | See `skills/sqlitedata.md` |6768### Automated Scanning6970**Core Data audit** → Launch `core-data-auditor` agent or `/axiom:audit core-data` (safety violations, architectural gaps — migration options, thread-confinement, N+1 queries, merge policies, context isolation)71**Codable audit** → Launch `codable-auditor` agent or `/axiom:audit codable` (safety violations, semantic gaps — try? swallowing errors, JSONSerialization, date handling, silent field drops, wrapper-hidden fallbacks, cross-file strategy drift, enum future-case crashes)72**iCloud audit** → Launch `icloud-auditor` agent or `/axiom:audit icloud` (entitlement checks, file coordination, incomplete CKError matrix coverage, missing account-change observation, polling vs CKSubscriptions, SwiftData + CloudKit unsupported features, compound risks like uncoordinated I/O across extensions)73**Storage audit** → Launch `storage-auditor` agent or `/axiom:audit storage` (wrong file locations, missing backup exclusions, sensitive data on disk vs Keychain, missing App Group containers, unbounded cache growth, orphan files, compound risks like user data in tmp/ + critical content)74**Database schema audit** → Launch `database-schema-auditor` agent or `/axiom:audit database-schema` (unsafe ALTER TABLE, DROP operations, missing idempotency, FK constraints declared but not enforced, incomplete upgrade paths, compound risks like INSERT OR REPLACE on FK-referenced tables)75**GRDB performance audit** → Launch `grdb-performance-auditor` agent or `/axiom:audit grdb-performance` (raw SQL string interpolation, missing FK indexes in raw SQL, missing PRAGMA optimize for raw-GRDB apps, journal mode mismatch for app-group DBs, missing observesSuspensionNotifications for shared DBs, prefix-redundant indexes in raw SQL, legacy Record subclass, INSERT OR REPLACE misused as upsert, observation on WITHOUT ROWID tables, WITHOUT ROWID upsert bugs)76**SwiftData audit** → Launch `swiftdata-auditor` agent or `/axiom:audit swiftdata` (struct models, missing schema registration, array relationships without defaults, background context misuse, N+1 patterns, stale predicates, CloudKit conformance gaps, compound risks like struct model + array relationship)7778## Decision Tree79801. SwiftData? → `skills/swiftdata.md`, `skills/swiftdata-migration.md`812. Core Data? → `skills/core-data.md`, `skills/core-data-diag.md`823. GRDB? → `skills/grdb.md`833a. GRDB perf, slow query, schema design for perf? → `skills/grdb-performance.md`843b. FTS5 (full-text search, any layer)? → `skills/sqlite-fts-ref.md`853c. DB shared across app + extension/widget/Live Activity? → `skills/grdb-app-groups.md`864. SQLiteData? → `skills/sqlitedata.md`, `skills/sqlitedata-ref.md`874a. `@Shared`/`@SharedReader`, or the loading/error state behind `@FetchAll`? → `skills/swift-sharing.md`885. ANY schema migration? → `skills/database-migration.md` (ALWAYS — prevents data loss)896. Realm migration? → `skills/realm-migration-ref.md`907. SwiftData vs SQLiteData? → `skills/sqlitedata-migration.md`918. Cloud sync architecture? → `skills/cloud-sync.md`929. CloudKit? → `skills/cloudkit-ref.md`9310. iCloud Drive? → `skills/icloud-drive-ref.md`9411. Cloud sync errors? → `skills/cloud-sync-diag.md`9512. Codable/JSON serialization? → `skills/codable.md`9613. File storage strategy? → `skills/storage.md`, `skills/storage-diag.md`, `skills/storage-management-ref.md`9714. File protection? → See axiom-security (skills/file-protection-ref.md)9815. Keychain / storing tokens, passwords, secrets securely? → See axiom-security (skills/keychain.md), See axiom-security (skills/keychain-diag.md), See axiom-security (skills/keychain-ref.md)9916. SecItem errors (errSecDuplicateItem, errSecItemNotFound, errSecInteractionNotAllowed)? → See axiom-security (skills/keychain-diag.md)10017. Encryption, signing, Secure Enclave, CryptoKit? → See axiom-security (skills/cryptokit.md), See axiom-security (skills/cryptokit-ref.md)10118. Quantum-secure cryptography, HPKE, ML-KEM? → See axiom-security (skills/cryptokit.md)10219. Want Core Data safety scan? → core-data-auditor (Agent)10320. Want Codable anti-pattern scan? → codable-auditor (Agent)10421. Want iCloud sync audit? → icloud-auditor (Agent)10522. Want storage location audit? → storage-auditor (Agent)10623. Want database schema/migration safety scan? → database-schema-auditor (Agent)10723a. Want GRDB performance/app-group scan? → grdb-performance-auditor (Agent)10824. Want SwiftData code audit? → swiftdata-auditor (Agent)10925. tvOS data persistence? → See axiom-swift (skills/tvos.md) (CRITICAL: every local directory is purgeable between launches, so iCloud is the source of truth) + `skills/sqlitedata.md` (CloudKit SyncEngine)11026. SwiftData @MainActor / background context threading? → `/skill axiom-concurrency`11127. Structured data generation with Foundation Models? → `/skill axiom-ai`112113#### Sync patterns114- HealthKit anchored/observer queries as a generalizable change-tracking pattern → See axiom-health (skills/sync-and-background.md)115116## Anti-Rationalization117118| Thought | Reality |119|---------|---------|120| "Just adding a column, no migration needed" | Schema changes without migration crash users. database-migration prevents data loss. |121| "I'll handle the migration manually" | Manual migrations miss edge cases. database-migration has the safe additive patterns and both migration paths to test. |122| "Simple query, I don't need the skill" | Query patterns prevent N+1 and thread-safety issues. The skill has copy-paste solutions. |123| "CloudKit sync is straightforward" | CloudKit has 15+ failure modes. cloud-sync-diag diagnoses them systematically. |124| "I know Codable well enough" | Codable has silent data loss traps (try? swallows errors). codable skill prevents production bugs. |125| "@Shared is just @AppStorage with extra steps" | Mutation goes through `$shared.withLock`; the plain setter is deprecated, and below Sharing 2.8 on Swift 6.3 it is a compile error wherever a SwiftUI binding is chained into shared state. swift-sharing has the migration. |126| "I'll use local storage on tvOS" | No local directory on tvOS is guaranteed to survive between launches — the system purges them, Caches first. See axiom-swift (skills/tvos.md) for the iCloud-first pattern. |127| "UserDefaults is fine for this token" | UserDefaults is unencrypted, backed up to iCloud, and visible to MDM profiles. One audit catches it. keychain stores tokens securely. |128| "I'll encrypt it myself with CommonCrypto" | CryptoKit replaced CommonCrypto's buffer-management nightmares with one-line APIs. cryptokit prevents misuse. |129130## Critical Pattern: Migrations131132**ALWAYS read `skills/database-migration.md` when adding/modifying database columns.**133134This prevents:135- "FOREIGN KEY constraint failed" errors136- "no such column" crashes137- Data loss from unsafe migrations138139## Example Invocations140141User: "I need to add a column to my SwiftData model"142→ Read: `skills/database-migration.md` (critical - prevents data loss)143144User: "How do I query SwiftData with complex filters?"145→ Read: `skills/swiftdata.md`146147User: "CloudKit sync isn't working"148→ Read: `skills/cloud-sync-diag.md`149150User: "Should I use SwiftData or SQLiteData?"151→ Read: `skills/sqlitedata-migration.md`152153User: "How do I persist a setting to UserDefaults and observe it everywhere?"154→ Read: `skills/swift-sharing.md`155156User: "Why is my @FetchAll empty — is it loading or did it fail?"157→ Read: `skills/swift-sharing.md`158159User: "Check my Core Data code for safety issues"160→ Launch: `core-data-auditor` agent161162User: "Scan for Codable anti-patterns before release"163→ Launch: `codable-auditor` agent164165User: "Audit my iCloud sync implementation"166→ Launch: `icloud-auditor` agent167168User: "Check if my files are stored in the right locations"169→ Launch: `storage-auditor` agent170171User: "Audit my database migrations for safety"172→ Launch: `database-schema-auditor` agent173174User: "How do I make my GRDB queries faster?"175→ Read: `skills/grdb-performance.md`176177User: "Add search to my GRDB-backed app" / "Add search to SQLiteData app"178→ Read: `skills/sqlite-fts-ref.md`179180User: "My widget needs to read the same database as the app"181→ Read: `skills/grdb-app-groups.md`182183User: "My widget shows stale data from the database"184→ Read: `skills/grdb-app-groups.md`185186User: "Audit my GRDB code for performance issues"187→ Launch: `grdb-performance-auditor` agent188189User: "Check my SwiftData models for issues"190→ Launch: `swiftdata-auditor` agent191192User: "How do I persist data on tvOS?"193→ Invoke: See axiom-swift (skills/tvos.md) + Read: `skills/sqlitedata.md`194195User: "My tvOS app loses data between launches"196→ Invoke: See axiom-swift (skills/tvos.md)197198User: "How do I store an auth token securely?"199→ Invoke: See axiom-security (skills/keychain.md)200201User: "errSecDuplicateItem but I checked and the item doesn't exist"202→ Invoke: See axiom-security (skills/keychain-diag.md)203204User: "How do I encrypt data with AES in Swift?"205→ Invoke: See axiom-security (skills/cryptokit.md)206207User: "I need to sign data with the Secure Enclave"208→ Invoke: See axiom-security (skills/cryptokit.md)209210User: "What's ML-KEM and should I use it?"211→ Invoke: See axiom-security (skills/cryptokit.md)
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