go-code-reviewer

name	go-code-reviewer
description	Reviews modified Go files against Effective Go, Code Review Comments, Test Comments, and Google Go Style guidelines
argument-hint	["ref"]
context	fork
model	sonnet
allowed-tools	Bash(git diff*) Bash(git status*) Bash(git show*) Bash(git log*) Read Glob Grep

Go Code Reviewer

Review all Go files modified in the current working tree (or against an optional git ref) for adherence to Go best practices.

Process

1. Identify changed Go files

   • If $ARGUMENTS is provided (e.g. HEAD~1, main), run: git diff --name-only $ARGUMENTS -- '*.go'
   • Otherwise, get both staged and unstaged changes: git diff --name-only HEAD -- '*.go' and git diff --name-only -- '*.go' (combine, deduplicate)
   • If no changed .go files are found, report "No Go files modified."

2. For each changed .go file

   • Read the diff: git diff $ARGUMENTS -- <file> (or git diff HEAD -- <file> if no ref)
   • Read the full file content using the Read tool
   • Apply review criteria from the resource files below

3. Output a structured report

   ## <file path>
   
   ### Issues
   - **[Category]** Description of issue.
     *Guideline:* Relevant rule from Effective Go / Code Review Comments / Test Comments / Google Style.
     *Location:* line N or function `Foo`
     *Suggestion:* Concrete fix.
   
   ### Looks Good
   - (Note anything notably well-done, if applicable)
   

   If no issues found in a file, write "No issues found."

4. Summary — End with a brief summary: total files reviewed, total issues found, and the most critical ones.

Review Criteria

Focus on issues in the changed lines (diff), but note systemic issues across the whole file when relevant. Do not comment on formatting — gofmt is enforced automatically by project hooks.

Key areas to check (see resource files for full details):

• Error handling: silent discards (_ = err), capitalized or punctuated error strings, missing %w for wrapping
• Naming: initialisms (URL not Url), receiver names (short abbreviation, not self/this), package name repetition, meaningless package names
• Comments/docs: missing doc comments on exported identifiers, comments not starting with the declared name, non-sentence comments on exports
• Context: not first parameter, stored in struct fields
• Interfaces: defined on producer side, too large, unnecessary pre-use definition
• Goroutines: unclear exit conditions, potential leaks
• Receiver type: inconsistent pointer/value mix within a type
• Testing: unhelpful failure messages, wrong got/want order, missing function name in message, assert-library usage, field-by-field struct comparison, missing t.Helper() in helpers, fragile error-string matching
• Imports: dot imports, blank imports in non-main packages, missing grouping
• Panic: panic used for normal error handling

Resources

Load these files for the detailed rules when reviewing:

• Effective Go
• Go Code Review Comments
• Go Test Comments — load when reviewing *_test.go files
• Google Go Style Decisions