python-project

A project setup guide for creating and modernising Python repositories with uv, a tool that manages Python versions, dependencies, builds, and publishing. It defines a src/ layout, locked dependencies, developer checks, and an application or library entry point.

In plain words
What is it for?
Use it to start a packaged Python application or importable library, add typed and tested code, configure tools such as Ruff and pytest, and prepare release wiring.
Why use it?
It removes the need to choose and configure separate tools for environments, packages, builds, and tests. The lock file and pinned interpreter help keep development consistent across machines.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/bitwise-media-group/skills/python-project
Any agent
npx skills add bitwise-media-group/skills --skill python-project
Clone the repo
git clone --depth 1 https://github.com/bitwise-media-group/skills

Made for: Claude Code, Codex.

Per session 226 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,280 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00226 $0.01280
Opus 5 $0.00113 $0.00640
Sonnet 5 $0.00045 $0.00256
Haiku 4.5 $0.00023 $0.00128

Measured yesterday against content hash 190c479dbf0b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

python-project scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

The scan reads SKILL.md. This mod also ships 1 executable file (templates/__main__.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

plugins/python/skills/python-project/SKILL.md · 92 lines

How it starts

The opening of the file, as written. The whole thing — 92 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Scaffold a Python project

Creates a Python repository with the src/ layout, uv-managed dependencies, pinned developer tooling, and a Makefile gate. Apply the python-style, python-typing, and python-testing skills while filling in real code, and wire releases with the python-release skill.

1. Initialize with uv

uv is the only tool for interpreters, virtual environments, dependencies, locking, building, and publishing — do not reach for pip, pipenv, poetry, conda, pyenv, or pipx alongside it.

uv init --package myapp   # packaged app with a CLI entry point and [build-system]
uv init --lib myapp       # importable library (same src/ layout, no console script)

Both flavors produce the src/ layout and a [build-system]; the bare uv init (flat, no build system) is only for throwaway scripts. uv writes pyproject.toml and src/myapp/, and the first uv sync/uv run writes the uv.lock you commit.

2. Lay out the tree

pyproject.toml
uv.lock              # committed — the reproducible, cross-platform resolution
.python-version      # pins the interpreter uv provisions for `uv run`
README.md            # referenced by `readme` in pyproject.toml
src/myapp/__init__.py
src/myapp/__main__.py
tests/
Makefile
  • src/ layout, never flat. Tests run against the installed package, so a missing __init__.py or a packaging mistake fails locally instead of being masked by an import-from-cwd. Copy templates/python-version to .python-version.
  • One module per concern, named for what it provides (store, client, config) — never utils, common, or helpers.

3. Configure pyproject.toml on the uv_build backend

Copy templates/pyproject.toml. The choices that matter:

  • [build-system] uses uv's native backendrequires = ["uv_build>=0.11.21,<0.12"], build-backend = "uv_build". It is fast and needs no configuration for the src/ layout; the upper bound keeps builds reproducible as the backend evolves.
  • requires-python is the floor (>=3.13); .python-version pins the interpreter used during development. Runtime dependencies use lower bounds (>=), never ==uv.lock does the exact pinning.
  • The [tool.ruff], [tool.ty.environment] (or [tool.pyright]), and [tool.pytest.ini_options] blocks ship in the same file; their rationale lives in the python-style, python-typing, and python-testing skills.

Read the full file on GitHub · 92 lines

Files

What ships with it

4 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 92 lines · 0 tokens per session scan A 190c479dbf0b

Subscribe to this mod's changes

python-project is a skill published in the GitHub repository bitwise-media-group/skills (2 stars, last pushed yesterday), licensed MIT. It adds 226 tokens to every session and 1,280 once invoked, about $0.0011 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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