dotnet-slopwatch

Slopwatch: LLM Anti-Cheat Quality Gate for .NET

Run the Slopwatch.Cmd dotnet tool as an automated quality gate after code modifications to detect "slop" -- shortcuts that make builds/tests pass without fixing real problems.

Scope

Slopwatch CLI installation and configuration
Running quality gate checks (disabled tests, suppressed warnings, empty catches)
Hook integration and CI/CD pipeline usage
Detection rule reference

Out of scope

Pattern recognition and manual code review for slop -- see [skill:dotnet-agent-gotchas] for Slopwatch anti-patterns

Prerequisites

.NET 8.0+ SDK
Slopwatch.Cmd NuGet package (v0.3.3+)

Cross-references: [skill:dotnet-tool-management] for general dotnet tool installation mechanics.

Installation

Local Tool (Recommended)

Add to .config/dotnet-tools.json:

{
  "version": 1,
  "isRoot": true,
  "tools": {
    "slopwatch.cmd": {
      "version": "0.3.3",
      "commands": ["slopwatch"],
      "rollForward": false
    }
  }
}

Then restore:

dotnet tool restore

Global Tool

dotnet tool install --global Slopwatch.Cmd

See [skill:dotnet-tool-management] for tool manifest conventions and restore patterns.

Usage

Basic Analysis

# Analyze current directory for slop
slopwatch analyze

# Analyze specific directory
slopwatch analyze -d ./src

# Strict mode -- fail on warnings too
slopwatch analyze --fail-on warning

# JSON output for tooling integration
slopwatch analyze --output json

# Show performance stats
slopwatch analyze --stats

First-Time Setup: Establish a Baseline

For existing projects with pre-existing issues, create a baseline so slopwatch only catches new slop. The init command scans all files and records current findings as the accepted baseline:

slopwatch init
git add .slopwatch/baseline.json
git commit -m "Add slopwatch baseline"

Updating the Baseline (Rare)

Only update when slop is truly justified and documented:

slopwatch analyze --update-baseline

Valid reasons: third-party library forces a pattern, intentional rate-limiting delay (not test flakiness), generated code that cannot be modified. Always add a code comment explaining the justification.

Configuration

Create .slopwatch/slopwatch.json to customize rules and exclusions:

{
  "minSeverity": "warning",
  "rules": {
    "SW001": { "enabled": true, "severity": "error" },
    "SW002": { "enabled": true, "severity": "warning" },
    "SW003": { "enabled": true, "severity": "error" },
    "SW004": { "enabled": true, "severity": "warning" },
    "SW005": { "enabled": true, "severity": "warning" },
    "SW006": { "enabled": true, "severity": "warning" }
  },
  "exclude": [
    "**/Generated/**",
    "**/obj/**",
    "**/bin/**"
  ]
}

Strict Mode (Recommended for LLM Sessions)

Elevate all rules to errors during LLM coding sessions:

{
  "minSeverity": "warning",
  "rules": {
    "SW001": { "enabled": true, "severity": "error" },
    "SW002": { "enabled": true, "severity": "error" },
    "SW003": { "enabled": true, "severity": "error" },
    "SW004": { "enabled": true, "severity": "error" },
    "SW005": { "enabled": true, "severity": "error" },
    "SW006": { "enabled": true, "severity": "error" }
  }
}

Detection Rules

Rule	Severity	What It Catches
SW001	Error	Disabled tests (`Skip=`, `Ignore`, `#if false`)
SW002	Warning	Warning suppression (`#pragma warning disable`, `SuppressMessage`)
SW003	Error	Empty catch blocks that swallow exceptions
SW004	Warning	Arbitrary delays in tests (`Task.Delay`, `Thread.Sleep`)
SW005	Warning	Project file slop (`NoWarn`, `TreatWarningsAsErrors=false`)
SW006	Warning	CPM bypass (`VersionOverride`, inline `Version` attributes)

When Slopwatch Flags an Issue

Understand why the shortcut was taken
Request a proper fix -- be specific about what's wrong
Verify the fix doesn't introduce different slop

# Example output
❌ SW001 [Error]: Disabled test detected
   File: tests/MyApp.Tests/OrderTests.cs:45
   Pattern: [Fact(Skip="Test is flaky")]

Never disable tests to achieve a green build. Fix the underlying issue.

Claude Code Hook Integration

Add slopwatch as a PostToolUse hook to automatically validate every edit. Create or update .claude/settings.json:

{
  "hooks": {
    "PostToolUse": [
      {
        "matcher": "Write|Edit|MultiEdit",
        "hooks": [
          {
            "type": "command",
            "command": "slopwatch analyze -d . --hook",
            "timeout": 60000
          }
        ]
      }
    ]
  }
}

The --hook flag:

Only analyzes git dirty files (fast, even on large repos)
Outputs errors to stderr in readable format
Blocks the edit on warnings/errors (exit code 2)
Claude sees the error and can fix it immediately

This is the pattern used by projects like BrighterCommand/Brighter.

CI/CD Integration

GitHub Actions

jobs:
  slopwatch:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Setup .NET
        uses: actions/setup-dotnet@v4
        with:
          dotnet-version: '8.0.x'  # any .NET 8+ SDK works

      - name: Install Slopwatch
        run: dotnet tool install --global Slopwatch.Cmd

      - name: Run Slopwatch
        run: slopwatch analyze -d . --fail-on warning

Azure Pipelines

- task: DotNetCoreCLI@2
  displayName: 'Install Slopwatch'
  inputs:
    command: 'custom'
    custom: 'tool'
    arguments: 'install --global Slopwatch.Cmd'

- script: slopwatch analyze -d . --fail-on warning
  displayName: 'Slopwatch Analysis'

Agent Gotchas

Do not suppress slopwatch findings. If slopwatch flags an issue, fix the code -- do not update the baseline or disable the rule without explicit user approval.
Run after every code change, not just at the end. Catching slop early prevents cascading shortcuts.
Use --hook flag in Claude Code hooks, not bare analyze. The hook flag restricts analysis to dirty files for performance.
Baseline is not a wastebasket. Adding items to the baseline requires documented justification. Never bulk-update baseline to silence warnings.
Local tool preferred over global. Use .config/dotnet-tools.json so the version is pinned and reproducible across team members.

Quick Reference

# First time setup
slopwatch init
git add .slopwatch/baseline.json

# After every code change
slopwatch analyze

# Strict mode (recommended)
slopwatch analyze --fail-on warning

# Hook mode (for Claude Code integration)
slopwatch analyze -d . --hook

# JSON output for tooling
slopwatch analyze --output json

# Update baseline (rare, document why)
slopwatch analyze --update-baseline

References

Slopwatch NuGet Package
[skill:dotnet-tool-management] -- dotnet tool installation and manifest conventions
[skill:dotnet-agent-gotchas] -- manual slop pattern recognition (visual detection counterpart)
[skill:dotnet-test-quality] -- test coverage and quality measurement