# Pytest Runner > Run pytest tests with automatic virtual environment activation. Use this skill whenever running tests, executing pytest, or when asked to "run tests", "test this", or any test execution task. Ensures venv is always activated before pytest runs. Use when this capability is needed. - Skill: `tomevault-io/pytest-runner-2` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/pytest-runner-2` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/pytest-runner-2/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Productivity - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/pytest-runner-2 --- # Pytest Runner Always activate the virtualenv before running pytest. Look for `.venv` in the project directory: ```bash source .venv/bin/activate && pytest --reuse-db -n ``` ## Test Selection Always specify which tests to run. Never run the entire suite without reason. Run most-likely-to-fail first: 1. New/changed test file specifically 2. Entire module the changes belong to 3. Entire project (only if needed) ## `--reuse-db` Always pass `--reuse-db` — unless you made model (database) changes beforehand, then omit it so the DB is recreated. ## Concurrency (`-n` flag) - **1 test**: `-n0` - **2-7 tests**: `-n` matching count (e.g. 3 tests → `-n 3`) - **8+ tests**: omit `-n` entirely --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/saleor) — claim your Tome and manage your conversions.