Find bugs in codebase

name: find-bugs description: Review the codebase for bugs and write findings to bugs-summary.md allowed-tools:

• Read
• Write
• Glob
• Grep
• Bash

Review the entire codebase for bugs and write a summary to bugs-summary.md in the project root.

Steps

1. Detect the project stack: Read build/manifest files (e.g., package.json, build.gradle.kts, Cargo.toml, go.mod, pyproject.toml, pom.xml) to identify the language, framework, and build tool.

2. Discover source files: Glob for production source files using patterns appropriate to the detected stack (e.g., src/**/*.ts, **/src/main/**/*.kt, **/*.go, src/**/*.py).

3. Discover test files: Glob for test files using the project's test directory conventions.

4. Read build configuration to understand dependencies, plugins, and build setup.

5. Read every source file to understand the full codebase before looking for issues.

6. Read every test file to understand what is already tested and whether tests are correct.

7. Run the test suite using the project's test command (e.g., npm test, ./gradlew test, cargo test, go test ./..., pytest) to check for failing tests.

8. Identify bugs by looking for:

   • Logic errors (incorrect conditionals, off-by-one, wrong operator)
   • Missing input validation or error handling
   • Mismatched test names vs assertions
   • Visibility issues (public API surface leaking internals)
   • Resource leaks (unclosed clients, streams, connections)
   • Thread safety issues
   • Serialization/deserialization mismatches
   • Silent failures (operations that fail without warning)
   • Incorrect or missing null/error handling
   • Duplicated code that has diverged (copy-paste bugs)

9. Check for design issues worth noting:

   • Hardcoded values that should be configurable
   • Equality/comparison semantics that may surprise callers
   • Missing API contracts or invariants

10. Write bugs-summary.md: Create or overwrite bugs-summary.md in the project root with the following structure:

    # Bug Summary
    
    ## Open
    
    ### 1. Short title
    
    **File:** `path/to/file.ext`
    
    Description of the bug, why it's a problem, and what the expected behavior should be.
    
    ### 2. ...
    
    ## Design Observations (not bugs, but worth noting)
    
    ### Short title
    
    Description.
    

    • Number each bug sequentially starting at 1
    • Include the file path and relevant line numbers
    • Explain both the problem and its impact
    • Separate true bugs from design observations
    • If a previous bugs-summary.md exists, read it first and preserve any items marked as "FIXED" in a Fixed section at the top

11. Report: Summarize how many bugs were found and give a brief overview of the findings.

Important

• Read all source files before reporting bugs — do not guess based on file names alone.
• Every reported bug must reference a specific file and describe a concrete problem.
• Do not report stylistic preferences or nitpicks as bugs.
• Do not make any code changes — only analyze and write the summary file.
• Run the tests to verify the current state; note any failures as bugs.