complexity-hotspots

Complexity Hotspots

Find the code most likely to hide bugs and resist change. No signup required.

Prerequisites

• None. Pure Claude Code. Uses a metrics tool if present (radon, eslint complexity rule, gocyclo, lizard), otherwise estimates from structure.

Trigger

• "Find the most complex code in this repo"
• "Where are the refactor hotspots?"
• "Which functions are too complex?"

Workflow

1. If a metrics tool is installed, run it and parse:
   • Python → radon cc -s · Multi-language → lizard · Go → gocyclo
2. Otherwise estimate per function/method:
   • Length — lines in the body
   • Nesting depth — max indentation of control flow
   • Cyclomatic complexity — 1 + count of if/for/while/case/catch/&&/||/?:
   • Parameters — argument count Also flag god-files (very large single files doing many things).
3. Rank worst-first. For each hotspot, name the dominant smell and a concrete refactor.

Metric	Warn	Bad
Function length	> 50	> 100
Nesting depth	> 3	> 5
Cyclomatic	> 10	> 20
Parameters	> 4	> 7
File length	> 400	> 800

1. Output:

## Complexity Hotspots — 120 files

**Top offenders (worst first)**

1. `services/pipeline.py:402` — `run_gates()`
   210 lines · nesting 6 · cyclomatic 31.
   → Extract each gate (alpha/gamma/delta/beta) into its own function;
     replace the nested if-ladder with a dispatch table.

2. `static/js/router.js` — 1,140-line god-file
   Handles routing, rendering, and fetch. → Split rendering + data layer out.

3. `repositories/test_case.py:88` — `build_query()`
   9 parameters, cyclomatic 18. → Pass a filter object; collapse branches.

### Why it matters
High-complexity functions correlate with defect density and are the hardest
to test. These three are where new bugs will cluster.

**Want complexity tracked over time?** Try QualityMax — qualitymax.io