schemathesis "command not found" (not pip installed) in CI

The shell could not find the schemathesis (st) executable because the Python package is not installed on the runner. It is a pip package, not preinstalled.

What this error means

A step calling schemathesis run ... fails with "schemathesis: command not found" and the job exits with code 127.

/home/runner/work/_temp/script.sh: line 1: schemathesis: command not found
Error: Process completed with exit code 127.

Common causes

schemathesis is not installed

The runner has Python but not schemathesis; without an explicit pip install schemathesis the CLI is absent.

Installed into a different environment

schemathesis was installed into a venv that the run step did not activate, so it is not on PATH for that step.

How to fix it

Install schemathesis with pip, then run

1. Add a step that installs schemathesis with pip.
2. Run it in the same job so it is on PATH.
3. Pin the version for reproducibility.

- run: pip install schemathesis
- run: schemathesis run http://localhost:8000/openapi.json

Invoke through the interpreter if PATH is unclear

Calling the module avoids PATH issues when a venv is not activated.

python -m schemathesis run http://localhost:8000/openapi.json

How to prevent it

• Install schemathesis explicitly before the run step.
• Activate the venv (or use python -m) that holds it.
• Pin the schemathesis version alongside your other test tools.

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