refactoring

Python Refactoring Analysis with pyscn

Run the pyscn CLI to locate concrete refactoring targets. No install needed: uvx pyscn@latest <command>.

Commands

User Request	Command
"Find complex functions"	uvx pyscn@latest analyze --select complexity <path>
"Find duplicate code"	uvx pyscn@latest analyze --select clones <path>
"Find dead code"	uvx pyscn@latest analyze --select deadcode <path>
"What should I refactor first?"	uvx pyscn@latest analyze --select complexity,deadcode,clones <path>

Key Flags

• --min-complexity <n>: minimum complexity to report (default: 5). Risk levels: Low (<10), Medium (10-20), High (>20)
• --clone-threshold <0.0-1.0>: minimum similarity for clone detection (default: 0.65)
• --min-severity <critical|warning|info>: dead code severity floor (default: warning). Critical means code after return/break/continue/raise that can never execute.
• --json: write a detailed report with line-level findings. Report files are NOT written to stdout; they go to .pyscn/reports/ and the path is printed on completion.

Prioritizing Findings

1. Critical dead code: safe deletions, do these first.
2. High-complexity functions (>20): extract functions, flatten conditionals.
3. Clone groups spanning multiple files: extract shared helpers; clones within one file are usually quicker wins.

When suggesting a refactor, cite the specific function names, files, and line ranges from the results, and re-run the same command afterward to confirm the improvement.

MCP Alternative

If the pyscn-mcp MCP server is connected, you can use its tools instead of the CLI: check_complexity (min_complexity), detect_clones (similarity_threshold, min_lines), find_dead_code, or analyze_code with analyses: ["complexity", "clone", "dead_code"] to run several at once. Results are returned inline with no report files.