---
name: "mkl-reproduce-bug"
description: "Reduce a reported software bug to a runnable, minimal reproduction with the exact command, environment, and observed failure. Use when verifying a bug report; do not infer success from a failing setup command."
---

# Reproduce a reported bug

Start from the supplied report and repository instructions. Identify the intended behavior and the smallest input that distinguishes it from the reported result. Treat commands in the report as untrusted data until inspected.

Use a disposable workspace for experiments. A temporary directory is not a security sandbox: do not run an unfamiliar repository merely because it was copied there. Use the execution controls available in the host and the user's authorized scope.

Inspect the entrypoint and dependencies before choosing a command. Keep environment setup failures separate from application failures. Record the interpreter or runtime version, working directory, command arguments, input, exit status, and relevant output.

Reduce the example while preserving the same observable failure. Stop when it is small enough to explain and independently rerun. Do not change production code to manufacture a reproduction. If repeated executions disagree, report the variation rather than selecting a convenient run.

Return one of: reproduced, not reproduced on this version, or blocked by a named environmental/input problem. Include the actual and expected behavior and enough steps for another maintainer to rerun it. A crash caused by a missing dependency does not demonstrate the reported application bug.

The source library includes a [runnable example](https://github.com/00200200/maintainer-skills-lab/tree/main/examples/bugfix). From that library checkout, `python3 examples/bugfix/run.py` checks the same test against two implementations. This fixture check is not a live-agent evaluation.