flake8-unused-arguments
flake8 extension to warn on unused function arguments
What it is and what it does
This is a flake8 plugin that integrates unused-argument detection into your linting workflow. It adds two warning codes—U100 for any unused argument and U101 for unused arguments starting with underscore—and lets you configure which function types to exclude from checking (abstract, overload, override, stub, dunder methods, lambdas, nested functions, and variadic parameters).
You install it alongside flake8, and it runs automatically as part of your linting pipeline. It's useful for catching dead parameters that clutter function signatures or indicate incomplete refactoring, though you can fine-tune it to avoid false positives in special cases like protocol implementations or intentionally-ignored parameters.
Use it for:
- Enforce code cleanup by catching function parameters that are declared but never used in the function body.
- Identify incomplete refactoring where parameters were removed from call sites but not from function signatures.
- Customize linting rules to skip dunder methods, abstract functions, or overrides that must match a parent signature.
- Integrate unused-argument checking into CI/CD pipelines via flake8 without adding a separate tool.
- Configure per-project rules via flake8 config files to ignore lambdas or nested functions if your codebase style prefers them.
Worth the install?
AI-flagged interpretation of the facts on this page — verify before relying
A flake8 plugin that detects unused function arguments in Python code and reports them as U100 or U101 warnings, with configurable rules to ignore specific function types.
Yes, if you use flake8 and want to catch unused function arguments. Install friction is minimal, no security issues are known, and the MIT license is unrestrictive. The aging maintenance status (291 days since last release) is a minor concern but the repository is still active and the plugin is straightforward enough that infrequent updates are not a red flag. It integrates seamlessly into existing flake8 workflows.
Install
flake8-unused-arguments on PyPI
pip
pip install flake8-unused-argumentsuv
uv add flake8-unused-argumentspoetry
poetry add flake8-unused-argumentsInstalling flake8-unused-arguments
Before you install
Low friction install as a pure Python wheel with only flake8 as a runtime dependency. Maintenance status is aging—last release was 291 days ago—but the repository remains active and unarchived with recent commits.
License in practice
MIT license is permissive and places no restrictions on use, modification, or redistribution in commercial or private projects.
Quickstart
pip install flake8-unused-arguments
Then add to your flake8 configuration or run:
flake8 --select=U100,U101 your_code.py
Or import in setup.cfg:
[flake8]
extend-select = U100, U101
Verify before relying
- Whether the plugin works with all currently maintained flake8 versions or has version constraints not specified in requires_python.
- Performance impact on large codebases or projects with thousands of functions.
Package facts
| License | MIT (permissive) |
| Python support | not specified |
| Install friction | low — pure-Python wheel |
| Runtime dependencies | 1 — flake8 |
| Maintenance | aging — 291 days since the last release |
| Last repo commit | |
| First released | |
| Downloads | 102,073/month — #12,893 on PyPI (30-day window, as of 2026-08-14) |
| Known vulnerabilities | none known (OSV.dev, checked 2026-08-14) |
Evidence: flake8_unused_arguments-0.0.14-py3-none-any.whl
Tags
More Python Modules packages
Converts domain names between Unicode and…
permissive · top 100 on PyPI
setuptoolsSetuptools is a Python build backend and…
permissive · top 100 on PyPI
PyYAMLPyYAML parses and emits YAML 1.1 data format,…
permissive · top 100 on PyPI
pydanticPydantic validates Python data structures…
permissive · top 100 on PyPI
annotated-typesProvides reusable metadata objects for use with…
permissive · top 100 on PyPI
typing-inspectionProvides runtime tools to inspect and…
permissive · top 100 on PyPI
flake8-returnA flake8 plugin that detects and flags…
permissive · top 15,000 on PyPI
flake8-annotationsA Flake8 plugin that enforces PEP 3107-style…
permissive · top 15,000 on PyPI
flake8-requirementsA flake8 plugin that validates whether imported…
permissive · top 15,000 on PyPI
flake8-builtinsA flake8 plugin that detects when Python…
copyleft · top 5,000 on PyPI
flake8-quotesA flake8 plugin that enforces consistent quote…
permissive · top 5,000 on PyPI
flake8-loggingA Flake8 plugin that detects and flags common…
permissive · top 15,000 on PyPI
uncalledDetects unused functions in Python projects…
permissive · top 15,000 on PyPI
flake8-bugbearA flake8 plugin that detects likely bugs and…
permissive · top 5,000 on PyPI
flake8-pyiA Flake8 plugin that lints Python type stub…
permissive · top 5,000 on PyPI
flake8-class-attributes-orderA flake8 extension that enforces a configurable…
permissive · top 15,000 on PyPI