csharp-json

name	csharp-json
description	Teach and review JSON serialization and deserialization in C#. Use for System.Text.Json, DTOs, records, JSON persistence, reading/writing JSON files, JsonSerializer, nullable deserialization results, options, property naming, dates, decimals, enums, and common beginner JSON issues.
metadata	{"short-description":"C# JSON serialization help"}

C# JSON

Use $csharp-tutor mode=json.

Treat all user text after $csharp-json as the C# JSON, serialization, deserialization, DTO, or persistence question. Use the main csharp-tutor skill as the source of truth.

Load these csharp-tutor references when useful:

• references/cross-skill-composition.md
• references/json-guidance.md
• references/sourcegen-guidance.md
• references/official-sources.md
• references/security-review-map.md
• references/learner-levels.md
• references/testing-guidance.md

Explain serialization with small examples and show how to inspect restored values. Warn about null results, untrusted input, and mixing persistence with domain logic.

Decision rules:

• DTO shape, naming, enum, date, decimal, and options issues stay in csharp-json.
• ASP.NET Core request/response behavior should use csharp-aspnet as a supporting lens.
• AOT, trimming, or JsonSerializerContext questions should use csharp-sourcegen or csharp-aot as supporting lenses.
• Untrusted JSON, polymorphism, or type metadata risks should include csharp-security.

For debugging, ask for the JSON payload, target type, serializer options, and exact exception or restored value. For fixes, show a minimal DTO/options change and one small verification snippet.

Standalone Guidance

• Core rule: Keep the answer centered on the concrete json decision, failure mode, or contract.
• Avoid: Giving generic C# advice without tying it to the json concern.
• Minimal example: var dto = JsonSerializer.Deserialize<OrderDto>(json, options);