How do I install the Bisect Bug skill?

Run npx skillmds@latest add uitbreidenos/bisect-bug in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Bisect Bug safe to use?

This skill has not completed SkillMD's automated safety review yet. Capability flags: makes network calls. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Bisect Bug?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Bisect Bug free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Bisect Bug?

UitbreidenOS (@uitbreidenos) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Bisect Bug by uitbreidenos — Agent Skill

Name: Bisect Bug
Rating: 4.666666666666667 (3 reviews)
Author: UitbreidenOS

File contents

Time-Travel Debugger (Git Bisect Integration)

When to activate

Activate when the user reports a regression ("this used to work, but now it's broken") and they don't know which commit caused the issue. Invoked via /bisect-bug.

When NOT to use

Do not use for newly written, uncommitted code. Do not use if the user already knows exactly where the bug is.

Instructions

Understand the Bug: Ask the user exactly what the bug is and how to reproduce it (e.g., "Run npm test src/auth.js and it fails" or "Curling /api/users returns 500").
Identify the Good Commit: Ask the user for a commit hash or branch name where they are certain the feature was still working (the "good" commit).
Write the Test Script:
- Create a file named bisect-test.sh in the project root.
- Write a deterministic bash script that tests for the bug.
- Crucial: The script must exit with code 0 if the code is GOOD (no bug), and exit with code 1 (or anything between 1 and 127) if the code is BAD (bug present).
- Make the script executable: chmod +x bisect-test.sh

Execute the Bisect:

Use the Bash tool to run the following sequence:

git bisect start
git bisect bad HEAD
git bisect good <GOOD_COMMIT_HASH>
git bisect run ./bisect-test.sh

Analyze the Result:
- Git will autonomously jump through history, running your script, until it finds the exact offending commit.
- Once it finishes, read the git output to identify the commit hash and author.
- Run git bisect reset to return the user's branch to normal.
- Read the offending commit's diff (git show <OFFENDING_COMMIT>).
Provide the Fix: Present the offending commit to the user, explain exactly why that specific change broke the code, and propose the fix. Delete bisect-test.sh.

Example

User: /bisect-bug The login endpoint is returning 500. It was definitely working in commit a1b2c3d. Claude: [Writes a curl script that exits 1 on HTTP 500]. [Runs git bisect autonomously in the bash terminal]. I found it! The bug was introduced 12 commits ago by Jane Doe in commit f9e8d7c. They removed the await keyword before the database call. I have reset your git tree. Shall I fix the missing await?

---name: bisect-bugdescription: Claude Code time-travel debugger (git bisect integration): workflow guidelines, best practices, instructions, and integration examples---# Time-Travel Debugger (Git Bisect Integration)## When to activateActivate when the user reports a regression ("this used to work, but now it's broken") and they don't know which commit caused the issue. Invoked via `/bisect-bug`.## When NOT to useDo not use for newly written, uncommitted code. Do not use if the user already knows exactly where the bug is.## Instructions1. **Understand the Bug:** Ask the user exactly what the bug is and how to reproduce it (e.g., "Run `npm test src/auth.js` and it fails" or "Curling `/api/users` returns 500").2. **Identify the Good Commit:** Ask the user for a commit hash or branch name where they are *certain* the feature was still working (the "good" commit).3. **Write the Test Script:** - Create a file named `bisect-test.sh` in the project root. - Write a deterministic bash script that tests for the bug. - **Crucial:** The script must exit with code `0` if the code is GOOD (no bug), and exit with code `1` (or anything between 1 and 127) if the code is BAD (bug present). - Make the script executable: `chmod +x bisect-test.sh`4. **Execute the Bisect:** - Use the `Bash` tool to run the following sequence: ```bash git bisect start git bisect bad HEAD git bisect good <GOOD_COMMIT_HASH> git bisect run ./bisect-test.sh ```5. **Analyze the Result:** - Git will autonomously jump through history, running your script, until it finds the exact offending commit. - Once it finishes, read the git output to identify the commit hash and author. - Run `git bisect reset` to return the user's branch to normal. - Read the offending commit's diff (`git show <OFFENDING_COMMIT>`).6. **Provide the Fix:** Present the offending commit to the user, explain exactly *why* that specific change broke the code, and propose the fix. Delete `bisect-test.sh`.## ExampleUser: `/bisect-bug The login endpoint is returning 500. It was definitely working in commit a1b2c3d.`Claude: [Writes a `curl` script that exits 1 on HTTP 500]. [Runs `git bisect` autonomously in the bash terminal].I found it! The bug was introduced 12 commits ago by Jane Doe in commit `f9e8d7c`. They removed the `await` keyword before the database call. I have reset your git tree. Shall I fix the missing `await`?

Frequently asked questions

Bisect Bug