What is find-regression-risk?

A mechanical checker that compares code removed in a pull request with code recently added by bug-fix pull requests in the same files.

Use it to review a pull request, inspect files changed by it, and get a CLEAN, OVERLAP, or REVERT result with structured findings.

It highlights possible regressions—new changes that may undo earlier fixes—without relying on an AI model.

How dotnet/maui configures Claude Code and Codex

About the project

.NET MAUI is a C# and XAML framework for building native mobile and desktop applications from one shared codebase. Developers use it to create apps for Android, iOS, iPadOS, macOS, and Windows. The catalogue entries provide skills, instructions, and agents for working with .NET MAUI.

dotnet/maui · 23,320 stars · on GitHub · dot.net

Reuse

Borrowing it

Nothing to install: this file belongs to dotnet/maui. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/dotnet/maui/main/.github/skills/find-regression-risk/SKILL.md

Clone the repo

git clone --depth 1 https://github.com/dotnet/maui

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/dotnet/maui/find-regression-risk.svg)](https://agentmods.dev/skills/dotnet/maui/find-regression-risk)

Your own site

<a href="https://agentmods.dev/skills/dotnet/maui/find-regression-risk"><img src="https://agentmods.dev/badge/skills/dotnet/maui/find-regression-risk.svg" alt="Measured on agentmods" height="20"></a>

Per session 160 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,197 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

Snyk warn 7 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.

Model	Per session	Once invoked
Fable 5.1	$0.00160	$0.01197
Opus 5	$0.00080	$0.00598
Sonnet 5	$0.00032	$0.00239
Haiku 4.5	$0.00016	$0.00120

Measured 8d ago against content hash db3fa84243f8, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

find-regression-risk 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 8d 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.

.github/skills/find-regression-risk/SKILL.md · 90 lines

How it starts

The opening of the file, as written. The whole thing — 90 lines — stays where its author put it; the contents beside it link to each section on GitHub.

find-regression-risk

Detects potential regression risks in a PR by cross-referencing removed lines against lines added by recent labeled bug-fix PRs.

How It Works

Purely mechanical — no AI/LLM. Five-step algorithm:

PR diff — collects lines REMOVED by the PR under review.
Git history — git log --follow --since=6mo finds recent PRs that touched the same files.
Label filter — keeps PRs (or their linked issues) labeled i/regression, t/bug, p/0, or p/1.
Fix diff — fetches each fix PR's diff and collects lines it ADDED to the same file.
Compare — whitespace-insensitive string equality:
- 🔴 REVERT — removed line matches a line a fix PR added (highest risk).
- 🟡 OVERLAP — same file modified, but no exact line revert.
- 🟢 CLEAN — no bug-fix PRs touch the same files.

Standalone Invocation

# Analyze a specific PR (auto-detects files)
pwsh -NoProfile -Command '& ./.github/scripts/Find-RegressionRisks.ps1 -PRNumber 33908 -OutputDir /tmp/out'

# Analyze specific files only
pwsh -NoProfile -Command '& ./.github/scripts/Find-RegressionRisks.ps1 -PRNumber 33908 -OutputDir /tmp/out -FilePaths @("src/Core/src/Platform/Android/MauiWindowInsetListener.cs")'

Parameters

Parameter	Required	Default	Description
`-PRNumber`	Yes	—	PR number to analyze
`-Repo`	No	`dotnet/maui`	Repository in `owner/name` form
`-FilePaths`	No	auto-detect	Implementation files to check
`-MonthsBack`	No	`6`	History window for git log
`-MaxRecentPRsPerFile`	No	`20`	Rate-limit guard per file
`-BaseBranch`	No	`main`	Base branch for `git log` scope
`-OutputDir`	No	—	Directory for output files
`-WriteInlineFindings`	No	off	Emit `inline-findings.json`

Outputs

When -OutputDir is specified:

result.txt — single token: CLEAN, OVERLAP, or REVERT
risks.json — structured findings for downstream agents
content.md — markdown summary for the PR comment
inline-findings.json — (only with -WriteInlineFindings) inline annotations

Read the full file on GitHub · 90 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.

8d ago First seen · 90 lines · 160 tokens per session scan A db3fa84243f8

Subscribe to this mod's changes

find-regression-risk is a skill published in the GitHub repository dotnet/maui (23,320 stars, last pushed today), licensed MIT. It adds 160 tokens to every session and 1,197 once invoked, about $0.0008 per session on Opus 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.

Code review dotnet hacktoberfest maui microsoft multi-platform user-interface

generate-code-cs

Generate the code from typespec for C#. Parameter: C# SDK repository root location .

Azure/azure-sdk-for-net · 26 tokens

build-sample-matrix

Build the matrix of all the samples throughout different frameworks.

Azure/azure-sdk-for-net · 17 tokens

translate-a-sample

Translate the Azure SDK sample from python to C# and generate markdownn file for the sample. Parameters: C# SDK repository root; python SDK repository root; Package name: one of Azure.AI.Projects, Azure.AI.Projects.Agents or Azure.AI.Extensions.OpenAI; The name of sample file in Python SDK repository.

Azure/azure-sdk-for-net · 90 tokens

maui: Skill for Claude Code