# Troubleshoot Abtest

> Debug ONE failing shaka-perf test at ONE viewport by attaching to its live browser — no MCP, no install. `shaka-perf troubleshoot` freezes the visreg + perf browsers open on the failing page; its own subcommands attach over CDP to inspect them. Use whenever a visreg mismatch or perf run needs eyes on the actual page — "why is this test failing", "look at the live page", "debug this abtest", "attach to the troubleshoot browser", "inspect the control vs experiment DOM".

- Skill: `shakacode/troubleshoot-abtest` (Agent Skill)
- Install (CLI): `npx skillmds@latest add shakacode/troubleshoot-abtest`
- Raw SKILL.md: https://api.skillmd.com/api/skills/shakacode/troubleshoot-abtest/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: AI & ML
- Author: shakacode (https://skillmd.com/u/shakacode)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/shakacode/troubleshoot-abtest

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# Troubleshooting a failing test on its live browser

`shaka-perf troubleshoot` runs one test at one viewport and leaves its visreg + perf browsers
frozen open on the failing page. Attach and inspect with its own subcommands over CDP — no MCP.

**Run `shaka-perf troubleshoot --help`** — it documents the whole loop (launch → `session` →
`eval` / `html` / `shot` / `console` → kill) and the per-command flags. Follow it.