A .NET code-generation workflow for producing C# and TypeScript source from code models and OpenAPI definitions. OpenAPI is a standard description of a web API, while Roslyn is Microsoft's toolkit for understanding C# code.

Use it to generate DTOs, managers, controllers, REST APIs, C# HttpClient code, and Angular or Axios TypeScript request clients.

It provides a defined place for parsing API descriptions, applying templates, and keeping generated files predictable. Regression tests help catch unwanted changes in generated output.

codegen — 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 codegen

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/codegen/github.svg)](https://agentmods.dev/skills/aterdev/perigon.cli/codegen)

Your own site

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

Per session 53 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 314 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	$0.00053	$0.00314
Opus 5.5	$0.00021	$0.00126
Sonnet 5.5	$0.00011	$0.00063
Haiku 4.5	$0.00005	$0.00031

Measured 1mo ago against content hash 854da80481c9, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

codegen 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/codegen/SKILL.md · 30 lines

What it actually says

Code Generation

Workflow

Inspect the relevant generator in src/CodeGenerator/Generate.
Inspect helpers in src/CodeGenerator/Helper before adding parsing logic.
Inspect templates in src/CodeGenerator/Templates when output text changes.
Inspect regression tests in tests/StudioMod.Tests/Generate.

Conventions

Prefer Roslyn APIs for C# syntax, symbols, namespaces, usings, attributes, and type analysis.
Prefer Microsoft.OpenApi APIs for OpenAPI traversal, schemas, and operations.
Keep parsing/model extraction in helpers and emitted output composition in generators or templates.
Avoid brittle string parsing when a structured API is available.
Keep generated output deterministic: stable ordering, whitespace, using lists, and no machine-specific paths.
Use raw string literals for embedded multi-line generated source.
Be careful around nullable values, enums, file uploads, path/query/body parameter placement, and special OpenAPI names.

Tests

Add focused tests under tests/StudioMod.Tests/Generate.
Use fixture OpenAPI files under tests/StudioMod.Tests/Generate/Fixtures.
For Roslyn helpers, use small source snippets that exercise the syntax or semantic case.

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 · 53 tokens per session scan A 854da80481c9

Subscribe to this mod's changes

codegen is a skill published in the GitHub repository AterDev/Perigon.CLI (54 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 53 tokens to every session and 314 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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