A set of guidelines for developing .NET applications, including their services, data storage, command-line interfaces, web interfaces, and MCP tools. MCP tools are interfaces that let an AI agent call application functions.

Use it when changing .NET services, managers, dependency injection, database persistence, data-transfer objects, mappings, logging, tests, CLI workflows, or MCP tool interfaces.

It helps keep shared code organized, dependencies flowing in the right direction, data access consistent, and long-running operations cancellable and testable.

dotnet — Skill for Claude Code and Codex by AterDev/Perigon.CLI

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 AterDev/Perigon.CLI --skill dotnet

Clone the repo

git clone --depth 1 https://github.com/AterDev/Perigon.CLI

Made for: Claude Code, Codex.

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/aterdev/perigon.cli/dotnet/github.svg)](https://agentmods.dev/skills/aterdev/perigon.cli/dotnet)

Your own site

<a href="https://agentmods.dev/skills/aterdev/perigon.cli/dotnet"><img src="https://agentmods.dev/badge/skills/aterdev/perigon.cli/dotnet/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.

Your own site · 80×15

<a href="https://agentmods.dev/skills/aterdev/perigon.cli/dotnet"><img src="https://agentmods.dev/badge/skills/aterdev/perigon.cli/dotnet.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 61 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 333 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

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.

Model	Per session	Once invoked
Fable 5.1	$0.00061	$0.00333
Opus 5.5	$0.00024	$0.00133
Sonnet 5.5	$0.00012	$0.00067
Haiku 4.5	$0.00006	$0.00033

Measured 1mo ago against content hash 36db1ab86079, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

dotnet 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 1mo 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.

.agents/skills/dotnet/SKILL.md · 30 lines

What it actually says

.NET Application Development

Workflow

Identify whether the change belongs in an app surface, service, manager, MCP tool, DTO/model, CodeGenerator, or Share.
Read the calling surface from CLI or Blazor before changing shared behavior.
Check shared entities and DefaultDbContext before changing persistence.
Preserve dependency direction: app projects depend on CoreMod; CoreMod depends on CodeGenerator and Share; Share stays foundational.

Conventions

Put cross-step workflows and external I/O in services.
Put MiniDb query/update behavior in managers.
Keep app-facing service methods stable when both CLI and Blazor consume them.
Use existing DTO patterns and Mapster helpers (MapTo, Merge, Adapt) where nearby code does.
Pass CancellationToken through file, HTTP, and long-running async operations.
Make HTTP services testable with injectable clients or handlers.
Log exceptions with structured logging before wrapping them in localized, user-friendly errors.
Keep MCP tools as protocol surfaces: stable parameter names, returned shapes, and no console output.

Tests

Add tests under tests/StudioMod.Tests/Services, Managers, or Commands depending on the observable behavior.
Stub HTTP and isolate filesystem/MiniDb state.

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.

1mo ago First seen · 30 lines · 61 tokens per session scan A 36db1ab86079

Subscribe to this mod's changes

dotnet is a skill published in the GitHub repository AterDev/Perigon.CLI (54 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 61 tokens to every session and 333 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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