Semantic Szz Analyzer

What it does

When your agent uses it

• Analyzing bug-fix commits to trace back to bug-introducing changes
• Investigating software evolution
• Conducting empirical studies on defect prediction
• Reducing false positives in bug localization

Example prompts

• “/semantic-szz-analyzer”

Requirements

• Python 3

Workflow steps

8 steps, taken from the step headings in SKILL.md.

1. 1Semantic Change Detection
2. 2Bug-Introducing Commit Identification
3. 3False Positive Reduction
4. 4Analyze Bug-Fix Commit
5. 5Identify Candidate Commits
6. 6Apply Semantic Analysis
7. 7Filter and Rank Results
8. 8Generate Explanation

What it can do on your machine

Read from SKILL.md and the folder at commit 4f38503. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  Ships 3 files in scripts/ (Python), which the agent can run.

  Shell commands in SKILL.md call:

  • python
  • git

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md. Its commands use git, which can reach the network depending on how they are called.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Semantic Szz Analyzer loads about 1.4k tokens when it runs, and up to ~6.6k if it reads all its reference files. Until then it costs about 138 tokens; SKILL.md has 466 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~138

When it runs · the whole SKILL.md, loaded when a task matches

~1.4k

With references · SKILL.md plus every file in references/, read only if the agent opens them

~6.6k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); the scripts in this folder are not scanned.

SKILL.md

The full file from ArabelaTso/Skills-4-SE at commit 4f38503, republished under its Apache-2.0 licence (© ArabelaTso). 466 words, ~1,407 tokens.

name

semantic-szz-analyzer

description

Identify bug-introducing commits using semantic analysis that extends traditional SZZ algorithm. Distinguishes semantic changes from refactorings or code movements using control-flow and data-flow similarity analysis. Use when analyzing bug-fix commits to trace back to bug-introducing changes, investigating software evolution, conducting empirical studies on defect prediction, or reducing false positives in bug localization. Supports git repositories and provides explanations for why commits are identified as bug-introducing.

git blame -L <start>,<end> <file> <bug-fix-commit>^

python scripts/semantic_analyzer.py --repo <repo-path> --candidate <commit-hash> --fix <fix-commit-hash>

python scripts/semantic_szz.py --repo /path/to/repo --fix-commit abc123

python scripts/batch_analyze.py --repo /path/to/repo --fixes-file bug_fixes.txt

python scripts/semantic_szz.py --repo /path/to/repo --fix-commit abc123 --output report.json --explain

# In scripts/semantic_analyzer.py
CFG_THRESHOLD = 0.7  # Control-flow similarity
DFG_THRESHOLD = 0.6  # Data-flow similarity
AST_THRESHOLD = 0.8  # AST structural similarity

python scripts/semantic_szz.py --repo /path/to/repo --issue JIRA-123

{
  "fix_commit": "abc123",
  "bug_introducing_commits": [
    {
      "commit": "def456",
      "confidence": 0.85,
      "semantic_change_type": "logic_modification",
      "explanation": "Modified conditional logic in function foo()",
      "changed_lines": [45, 46, 47],
      "similarity_scores": {
        "cfg": 0.72,
        "dfg": 0.68,
        "ast": 0.81
      }
    }
  ]
}

© ArabelaTso, Apache-2.0. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 8 other files (scripts, references) in skills/semantic-szz-analyzer of ArabelaTso/Skills-4-SE.

• SKILL.md
• README.md
• bug_fixes.txt.example
• references/language_support.md
• references/semantic_analysis.md
• references/szz_algorithm.md
• scripts/batch_analyze.py
• scripts/semantic_analyzer.py
• scripts/semantic_szz.py

Open the folder on GitHubat commit 4f38503