pyscn¶

A structural static analyzer for Python. Detects dead code, duplication, complexity, and coupling issues via control-flow and tree analysis.

uvx pyscn@latest analyze .

Features¶

32 rules across unreachable code, duplicate code, complexity, class design, dependency injection, module structure, and mock data.
CFG-based reachability finds dead code past return / raise / break / continue and unreachable branches.
APTED + LSH clone detection across four clone types (identical, renamed, modified, semantic).
CBO / LCOM4 class coupling and cohesion metrics.
Circular import detection via Tarjan's SCC.
Health score (0–100) with per-category breakdown.
CI-ready with pyscn check, linter-style output, and deterministic exit codes.
MCP server (pyscn-mcp) for Claude Code, Cursor, and other MCP clients.

Written in Go. 100,000+ lines/sec on typical hardware. No Python runtime dependencies.

Installation¶

uvx pyscn@latest <command>   # run without installing (recommended)
uv tool install pyscn        # install with uv
pipx install pyscn           # install with pipx
pip install pyscn            # install with pip

See Installation for all options.

Quick start¶

pyscn analyze .                         # full analysis, HTML report
pyscn check --select complexity,deadcode src/   # CI gate
pyscn init                              # generate .pyscn.toml

See Quick Start and the Rule catalog.