guide-swiftdata
SwiftData patterns — autosave, relationships, dangerous predicates, CloudKit constraints, indexing, class inheritance. Use when writing, reviewing, or debugging SwiftData code.
70
88%
Does it follow best practices?
Run evals on this skill
Adds up to 20 points to the overall score
Passed
No findings from the security scan
Guide Skill — This is an expert workflow/pattern guide, not API reference documentation. Originally from twostraws/SwiftData-Agent-Skill by Paul Hudson. MIT License.
SwiftData Patterns
Write and review SwiftData code for correctness, modern API usage, and adherence to project conventions. Report only genuine problems — do not nitpick or invent issues.
Core Instructions
- Target Swift 6.2 or later, using modern Swift concurrency.
- Prefer SwiftData across the board. Do not suggest Core Data unless the feature cannot be solved with SwiftData.
- Do not introduce third-party frameworks without asking first.
Review Process
- Check for core SwiftData issues using
references/core-rules.md. - Check that predicates are safe and supported using
references/predicates.md. - If the project uses CloudKit, check for CloudKit-specific constraints using
references/cloudkit.md. - If the project targets iOS 18+, check for indexing opportunities using
references/indexing.md. - If the project targets iOS 26+, check for class inheritance patterns using
references/class-inheritance.md.
If doing partial work, load only the relevant reference files.
References
| Topic | Reference |
|---|---|
Autosave, relationships, delete rules, @Query restrictions, #Unique, @Transient | references/core-rules.md |
| Supported predicates, dangerous patterns that crash at runtime, unsupported methods | references/predicates.md |
CloudKit constraints: no #Unique, optional requirements, eventual consistency | references/cloudkit.md |
| Database indexing (iOS 18+), single and compound property indexes | references/indexing.md |
Model subclassing (iOS 26+), @available requirements, predicate filtering | references/class-inheritance.md |
- Repository
Prisma-Labs-Dev/apple-skills
- Revision
4986260
- Last updated
- First committed
Is this your skill?
If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.