serialization

serialization is a skill for Claude Code from Aaronontheweb/dotnet-skills. It costs 44 tokens per session (2,558 once invoked), scanned A, original, MIT.

Guidance for choosing how .NET programs turn data into formats they can send, store, or read later. It compares formats such as Protocol Buffers, MessagePack, and JSON, including how they handle compatibility and performance.

In plain words
What is it for?
Use it when designing APIs, messages between services, stored data, gRPC communication, or a move from Newtonsoft.Json to System.Text.Json.
Why use it?
It helps avoid choosing a format that is difficult to update, slow, or unsuitable for systems built ahead of time without runtime type inspection. It also explains when each option fits common .NET uses.

Skill for Claude Code

Written for Claude Code: user-invocable in frontmatter.

Part of the dotnet-skills plugin — 39 skills, 6 agents shipped together

Good fit Use it when designing APIs, messages between services, stored data, gRPC communication, or a move from Newtonsoft.Json to System.Text.Json.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/aaronontheweb/dotnet-skills/serialization
About the project

.NET Skills is an AI coding plugin that provides skills and specialized guidance for professional .NET development, covering areas such as C#, Akka.NET, Aspire, Entity Framework Core, testing, and performance. .NET developers use it with coding assistants to apply production-oriented patterns while building and maintaining applications. The catalogue contains the plugin’s skills, agents, and instructions.

Aaronontheweb/dotnet-skills · 1,241 stars · on GitHub

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add Aaronontheweb/dotnet-skills --skill serialization
Clone the repo
git clone --depth 1 https://github.com/Aaronontheweb/dotnet-skills

Made for: Claude Code.

Or install dotnet-skills, the plugin that ships this one along with the rest of its 39 skills, 6 agents.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for serialization

README.md
[![agentmods](https://agentmods.dev/badge/skills/aaronontheweb/dotnet-skills/serialization/github.svg)](https://agentmods.dev/skills/aaronontheweb/dotnet-skills/serialization)
Your own site
<a href="https://agentmods.dev/skills/aaronontheweb/dotnet-skills/serialization"><img src="https://agentmods.dev/badge/skills/aaronontheweb/dotnet-skills/serialization/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for serialization

Your own site · 80×15
<a href="https://agentmods.dev/skills/aaronontheweb/dotnet-skills/serialization"><img src="https://agentmods.dev/badge/skills/aaronontheweb/dotnet-skills/serialization.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 44 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,558 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • Socket pass 15 Sept 2026
  • Snyk pass 15 Sept 2026
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00044 $0.02558
Opus 5.5 $0.00018 $0.01023
Sonnet 5.5 $0.00009 $0.00512
Haiku 4.5 $0.00004 $0.00256

Measured 18d ago against content hash 9ab830f2c21a, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

serialization scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 18d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

Copies of this mod

2 near-identical copies found in the catalogue:

skills/serialization/SKILL.md · 414 lines

How it starts

The opening of the file, as written. The whole thing — 414 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Serialization in .NET

When to Use This Skill

Use this skill when:

  • Choosing a serialization format for APIs, messaging, or persistence
  • Migrating from Newtonsoft.Json to System.Text.Json
  • Implementing AOT-compatible serialization
  • Designing wire formats for distributed systems
  • Optimizing serialization performance

Schema-Based vs Reflection-Based

Aspect Schema-Based Reflection-Based
Examples Protobuf, MessagePack, System.Text.Json (source gen) Newtonsoft.Json, BinaryFormatter
Type info in payload No (external schema) Yes (type names embedded)
Versioning Explicit field numbers/names Implicit (type structure)
Performance Fast (no reflection) Slower (runtime reflection)
AOT compatible Yes No
Wire compatibility Excellent Poor

Recommendation: Use schema-based serialization for anything that crosses process boundaries.


Format Recommendations

Use Case Recommended Format Why
REST APIs System.Text.Json (source gen) Standard, AOT-compatible
gRPC Protocol Buffers Native format, excellent versioning
Actor messaging MessagePack or Protobuf Compact, fast, version-safe
Event sourcing Protobuf or MessagePack Must handle old events forever
Caching MessagePack Compact, fast
Configuration JSON (System.Text.Json) Human-readable
Logging JSON (System.Text.Json) Structured, parseable

Formats to Avoid

Format Problem
BinaryFormatter Security vulnerabilities, deprecated, never use
Newtonsoft.Json default Type names in payload break on rename
DataContractSerializer Complex, poor versioning
XML Verbose, slow, complex

System.Text.Json with Source Generators

For JSON serialization, use System.Text.Json with source generators for AOT compatibility and performance.

Read the full file on GitHub · 414 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 18d ago Changed 9ab830f2c21a
  2. 1mo ago First seen · 414 lines · 44 tokens per session scan A 0f1f25452107

Subscribe to this mod's changes

serialization is a skill published in the GitHub repository Aaronontheweb/dotnet-skills (1,241 stars, last pushed 16d ago), licensed MIT. It adds 44 tokens to every session and 2,558 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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