Code reviewer

Code review automation for TypeScript, JavaScript, Python, Go, Swift, Kotlin, C#, .NET, Java, C, C++, Rust, Ruby, PHP, and Dart/Flutter.

How to use it

Claude Code
  1. Run the line below. It pulls the whole folder into ~/.claude/skills/code-reviewer-2, including the files SKILL.md points to.
  2. Describe your job in plain words. Claude Code follows the skill from there.
Claude Code — installs the whole folder, not just SKILL.md
npx degit alirezarezvani/claude-skills/engineering-team/skills/code-reviewer#main ~/.claude/skills/code-reviewer-2

For one project only, change the path to .claude/skills/code-reviewer-2. This skill also uses universal.md, python.md, typescript.md, go.md, swift.md, kotlin.md — copying SKILL.md alone won't be enough. See the folder on GitHub.

Claude (web or desktop app)
  1. On this page open ⋯ → Download .md.
  2. Save it as SKILL.md in a folder, zip the folder, then Customize → Skills → + → Create skill → Upload a skill.
  3. Pick the file and Save. Claude shows the name and description and runs a security scan.
  4. Check the skill is switched on.
  5. Start a new chat and describe your job in plain words. The AI follows the skill from there.
ChatGPT or another app
  1. ChatGPT: make a Project and paste it into Instructions.
  2. Neither? Paste it at the top of a new chat — it works for that chat.
Not working?
  • Check which app you pasted it into — the steps above name the right one.
  • Some skills need the paid tier of Claude or ChatGPT.
Step-by-step guide with screenshots · Ask in the forum

Paste into Claude, ChatGPT or Cursor.

Source of Code reviewer

Show the full text184 lines
namedescription
code-reviewerCode review automation for TypeScript, JavaScript, Python, Go, Swift, Kotlin, C#, .NET, Java, C, C++, Rust, Ruby, PHP, and Dart/Flutter. Analyzes PRs for complexity and risk, checks code quality for SOLID violations and code smells, generates review reports. Use when reviewing pull requests, analyzing code quality, identifying issues, generating review checklists.

Code Reviewer

Automated code review tools for analyzing pull requests, detecting code quality issues, and generating review reports.


How This Skill Is Organized

code-reviewer/
  SKILL.md                        ← you are here (tools + dispatch table)
  rules/
    universal.md                  ← security, async, resources, exceptions, performance — all languages
  languages/
    python.md                     ← Python-specific rules + idioms
    typescript.md                 ← TypeScript / JavaScript-specific rules + idioms
    go.md                         ← Go-specific rules + idioms
    swift.md                      ← Swift-specific rules + idioms
    kotlin.md                     ← Kotlin-specific rules + idioms
    csharp.md                     ← C# / .NET-specific rules + idioms
    java.md                       ← Java-specific rules + idioms
    c.md                          ← C -specific rules + idioms
    cpp.md                        ← C++ -specific rules + idioms
    rust.md                       ← Rust -specific rules + idioms
    ruby.md                       ← Ruby -specific rules + idioms
    php.md                        ← PHP-specific rules + idioms
    dart.md                       ← Dart / Flutter-specific rules + idioms
Loading order for every review
  1. This file (SKILL.md) — tools and thresholds
  2. rules/universal.md — always, for every language
  3. The matching languages/*.md — one file based on the extension table below

That is always exactly 2 additional files, regardless of scope.

Extension(s) Load
.py languages/python.md
.ts, .tsx, .js, .jsx, .mjs languages/typescript.md
.go languages/go.md
.swift languages/swift.md
.kt, .kts languages/kotlin.md
.cs, .csx, .razor, .cshtml languages/csharp.md
.java languages/java.md
.c, .h languages/c.md
.cpp, .cc, .cxx, .hpp, .hh, .hxx languages/cpp.md
.rs languages/rust.md
.rb, .rake, .gemspec, .ru languages/ruby.md
.php, .phtml languages/php.md
.dart languages/dart.md

Tools

PR Analyzer

Analyzes git diff between branches to assess review complexity and identify risks.

# Analyze current branch against main
python scripts/pr_analyzer.py /path/to/repo

# Compare specific branches
python scripts/pr_analyzer.py . --base main --head feature-branch

# JSON output for integration
python scripts/pr_analyzer.py /path/to/repo --json

What it detects (universal — see also language file for language-specific signals):

  • Hardcoded secrets (passwords, API keys, tokens, connection strings)
  • SQL / query injection patterns
  • Debug statements left in production code
  • Lint / analyzer suppression annotations
  • TODO/FIXME comments

Language-specific detections are defined in each languages/*.md file.

Output includes:

  • Complexity score (1-10)
  • Risk categorization (critical, high, medium, low)
  • File prioritization for review order
  • Commit message validation

Code Quality Checker

Analyzes source code for structural issues, code smells, and SOLID violations.

# Analyze a directory
python scripts/code_quality_checker.py /path/to/code

# Analyze specific language
# Valid values: python, typescript, javascript, go, swift, kotlin, csharp, java, c, cpp, rust, ruby, php, dart
python scripts/code_quality_checker.py . --language java

# JSON output
python scripts/code_quality_checker.py /path/to/code --json

Universal thresholds:

Issue Threshold
Long function >50 lines
Large file >500 lines
God class >20 methods
Too many params >5
Deep nesting >4 levels
High complexity >10 branches

Language-specific checks are defined in each languages/*.md file.


Review Report Generator

Combines PR analysis and code quality findings into structured review reports.

# Generate report for current repo
python scripts/review_report_generator.py /path/to/repo

# Markdown output
python scripts/review_report_generator.py . --format markdown --output review.md

# Use pre-computed analyses
python scripts/review_report_generator.py . \
  --pr-analysis pr_results.json \
  --quality-analysis quality_results.json

Verdicts:

Score Verdict
90+ with no high issues Approve
75+ with ≤2 high issues Approve with suggestions
50-74 Request changes
<50 or critical issues Block

Adding a New Language

Reviewer guidance (required):

  1. Create languages/<name>.md using any existing language file as a template — it must have sections: PR Analyzer Signals, Code Quality Checks, Security, Async, Resource Management, Exception Handling, Performance, Idioms.
  2. Add the extension row to the dispatch table above.

That is all the agent-driven review needs.

Deterministic analyzer support (optional, recommended): the bundled scripts only flag a language they explicitly know. To make code_quality_checker.py score the new language:

  1. Add the extensions to LANGUAGE_EXTENSIONS in scripts/code_quality_checker.py (this also adds the --language choice).
  2. Add function / class / method regex entries for the language in the same file; otherwise it falls back to the Python patterns.
  3. Optionally add a check_<name>_specific_smells(...) detector (see the C#, Java, and C ones) and call it from analyze_file.
  4. Add assets/sample_<name>_smells.<ext> + _clean fixtures and commit the expected --json output under expected_outputs/ as a regression guard.

Regression Fixtures

Labelled fixtures live in assets/ with their committed --json output in expected_outputs/ (C#, Java, and C). Drift from the committed JSON signals a behaviour change in the analyzer:

python scripts/code_quality_checker.py assets/sample_java_smells.java --json \
  | diff - expected_outputs/sample_java_smells_quality.json
1---
2name: "code-reviewer"
3description: Code review automation for TypeScript, JavaScript, Python, Go, Swift, Kotlin, C#, .NET, Java, C, C++, Rust, Ruby, PHP, and Dart/Flutter. Analyzes PRs for complexity and risk, checks code quality for SOLID violations and code smells, generates review reports. Use when reviewing pull requests, analyzing code quality, identifying issues, generating review checklists.
4---
5 
6# Code Reviewer
7 
8Automated code review tools for analyzing pull requests, detecting code quality issues, and generating review reports.
9 
10---
11 
12## How This Skill Is Organized
13 
14```
15code-reviewer/
16 SKILL.md ← you are here (tools + dispatch table)
17 rules/
18 universal.md ← security, async, resources, exceptions, performance — all languages
19 languages/
20 python.md ← Python-specific rules + idioms
21 typescript.md ← TypeScript / JavaScript-specific rules + idioms
22 go.md ← Go-specific rules + idioms
23 swift.md ← Swift-specific rules + idioms
24 kotlin.md ← Kotlin-specific rules + idioms
25 csharp.md ← C# / .NET-specific rules + idioms
26 java.md ← Java-specific rules + idioms
27 c.md ← C -specific rules + idioms
28 cpp.md ← C++ -specific rules + idioms
29 rust.md ← Rust -specific rules + idioms
30 ruby.md ← Ruby -specific rules + idioms
31 php.md ← PHP-specific rules + idioms
32 dart.md ← Dart / Flutter-specific rules + idioms
33```
34 
35### Loading order for every review
36 
371. This file (`SKILL.md`) — tools and thresholds
382. `rules/universal.md` — always, for every language
393. The matching `languages/*.md` — one file based on the extension table below
40 
41That is always exactly **2 additional files**, regardless of scope.
42 
43| Extension(s) | Load |
44|---|---|
45| `.py` | `languages/python.md` |
46| `.ts`, `.tsx`, `.js`, `.jsx`, `.mjs` | `languages/typescript.md` |
47| `.go` | `languages/go.md` |
48| `.swift` | `languages/swift.md` |
49| `.kt`, `.kts` | `languages/kotlin.md` |
50| `.cs`, `.csx`, `.razor`, `.cshtml` | `languages/csharp.md` |
51| `.java` | `languages/java.md` |
52| `.c`, `.h` | `languages/c.md` |
53| `.cpp`, `.cc`, `.cxx`, `.hpp`, `.hh`, `.hxx` | `languages/cpp.md` |
54| `.rs` | `languages/rust.md` |
55| `.rb`, `.rake`, `.gemspec`, `.ru` | `languages/ruby.md` |
56| `.php`, `.phtml` | `languages/php.md` |
57| `.dart` | `languages/dart.md` |
58 
59---
60 
61## Tools
62 
63### PR Analyzer
64 
65Analyzes git diff between branches to assess review complexity and identify risks.
66 
67```bash
68# Analyze current branch against main
69python scripts/pr_analyzer.py /path/to/repo
70 
71# Compare specific branches
72python scripts/pr_analyzer.py . --base main --head feature-branch
73 
74# JSON output for integration
75python scripts/pr_analyzer.py /path/to/repo --json
76```
77 
78**What it detects (universal — see also language file for language-specific signals):**
79- Hardcoded secrets (passwords, API keys, tokens, connection strings)
80- SQL / query injection patterns
81- Debug statements left in production code
82- Lint / analyzer suppression annotations
83- TODO/FIXME comments
84 
85**Language-specific detections** are defined in each `languages/*.md` file.
86 
87**Output includes:**
88- Complexity score (1-10)
89- Risk categorization (critical, high, medium, low)
90- File prioritization for review order
91- Commit message validation
92 
93---
94 
95### Code Quality Checker
96 
97Analyzes source code for structural issues, code smells, and SOLID violations.
98 
99```bash
100# Analyze a directory
101python scripts/code_quality_checker.py /path/to/code
102 
103# Analyze specific language
104# Valid values: python, typescript, javascript, go, swift, kotlin, csharp, java, c, cpp, rust, ruby, php, dart
105python scripts/code_quality_checker.py . --language java
106 
107# JSON output
108python scripts/code_quality_checker.py /path/to/code --json
109```
110 
111**Universal thresholds:**
112 
113| Issue | Threshold |
114|-------|-----------|
115| Long function | >50 lines |
116| Large file | >500 lines |
117| God class | >20 methods |
118| Too many params | >5 |
119| Deep nesting | >4 levels |
120| High complexity | >10 branches |
121 
122Language-specific checks are defined in each `languages/*.md` file.
123 
124---
125 
126### Review Report Generator
127 
128Combines PR analysis and code quality findings into structured review reports.
129 
130```bash
131# Generate report for current repo
132python scripts/review_report_generator.py /path/to/repo
133 
134# Markdown output
135python scripts/review_report_generator.py . --format markdown --output review.md
136 
137# Use pre-computed analyses
138python scripts/review_report_generator.py . \
139 --pr-analysis pr_results.json \
140 --quality-analysis quality_results.json
141```
142 
143**Verdicts:**
144 
145| Score | Verdict |
146|-------|---------|
147| 90+ with no high issues | Approve |
148| 75+ with ≤2 high issues | Approve with suggestions |
149| 50-74 | Request changes |
150| <50 or critical issues | Block |
151 
152---
153 
154## Adding a New Language
155 
156**Reviewer guidance (required):**
157 
1581. Create `languages/<name>.md` using any existing language file as a template — it must have sections: PR Analyzer Signals, Code Quality Checks, Security, Async, Resource Management, Exception Handling, Performance, Idioms.
1592. Add the extension row to the dispatch table above.
160 
161That is all the agent-driven review needs.
162 
163**Deterministic analyzer support (optional, recommended):** the bundled scripts
164only flag a language they explicitly know. To make `code_quality_checker.py`
165score the new language:
166 
1673. Add the extensions to `LANGUAGE_EXTENSIONS` in `scripts/code_quality_checker.py` (this also adds the `--language` choice).
1684. Add `function` / `class` / `method` regex entries for the language in the same file; otherwise it falls back to the Python patterns.
1695. Optionally add a `check_<name>_specific_smells(...)` detector (see the C#, Java, and C ones) and call it from `analyze_file`.
1706. Add `assets/sample_<name>_smells.<ext>` + `_clean` fixtures and commit the expected `--json` output under `expected_outputs/` as a regression guard.
171 
172---
173 
174## Regression Fixtures
175 
176Labelled fixtures live in `assets/` with their committed `--json` output in
177`expected_outputs/` (C#, Java, and C). Drift from the committed JSON signals a
178behaviour change in the analyzer:
179 
180```bash
181python scripts/code_quality_checker.py assets/sample_java_smells.java --json \
182 | diff - expected_outputs/sample_java_smells_quality.json
183```
184 

Discussion

Alternatives

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