What is playwright-debugging-traces-and-flake-reduction?

A guide for investigating unreliable Playwright browser tests, including tests that fail only in continuous integration (CI), the automated build-and-test environment.

Use it to inspect traces, debug with the Playwright inspector or UI mode, clean up code generated by codegen, and turn flaky failures into explicit fixes.

It helps find the timing or synchronization problem behind an intermittent failure instead of hiding it with retries.

playwright-debugging-traces-and-flake-reductio

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent

npx skills add andrewsrigom/agent-skills --skill playwright-debugging-traces-and-flake-reduction

Clone the repo

git clone --depth 1 https://github.com/andrewsrigom/agent-skills

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/andrewsrigom/agent-skills/playwright-debugging-traces-and-flake-reduction/github.svg)](https://agentmods.dev/skills/andrewsrigom/agent-skills/playwright-debugging-traces-and-flake-reduction)

Your own site

<a href="https://agentmods.dev/skills/andrewsrigom/agent-skills/playwright-debugging-traces-and-flake-reduction"><img src="https://agentmods.dev/badge/skills/andrewsrigom/agent-skills/playwright-debugging-traces-and-flake-reduction/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/andrewsrigom/agent-skills/playwright-debugging-traces-and-flake-reduction"><img src="https://agentmods.dev/badge/skills/andrewsrigom/agent-skills/playwright-debugging-traces-and-flake-reduction.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 57 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 677 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00057	$0.00677
Opus 5.5	$0.00023	$0.00271
Sonnet 5.5	$0.00011	$0.00135
Haiku 4.5	$0.00006	$0.00068

Measured 2mo ago against content hash fc527dda504d, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

playwright-debugging-traces-and-flake-reduction scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

playwright/playwright-debugging-traces-and-flake-reduction/SKILL.md · 77 lines

How it starts

The opening of the file, as written. The whole thing — 77 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Playwright Debugging Traces And Flake Reduction

Use this skill when the problem is unreliable test behavior or poor observability during failure analysis.

Scope

trace viewer
inspector and UI mode
codegen as a debugging aid
CI-only flake investigation
turning failures into explicit synchronization or contract fixes

Routing cues

flaky tests, CI-only failures, trace viewer, show-trace, UI mode, inspector, PWDEBUG, codegen, or finding the real source of instability -> use this skill
if the issue is clearly just a bad locator or weak assertion -> use playwright-locators-assertions-and-user-visible-contracts
if the issue is clearly auth reuse or stale storage state -> use playwright-auth-projects-and-isolation
if the issue is clearly backend timing or mocking boundaries -> use playwright-network-control-and-api-synchronization

Default path

Reproduce the failure with traces enabled.
Inspect the failing step in Trace Viewer before changing the test.
Use UI mode or inspector when an interactive run clarifies the timing or locator issue.
Use codegen only to discover robust locators or interaction flow, then clean the generated code aggressively.
Fix the root contract: locator, assertion, synchronization, auth state, or environment setup.

When to deviate

Increase trace capture only when the existing signal is insufficient.
Use video or screenshot artifacts when traces alone do not explain a visual issue.
Add targeted debug logging only when the trace and inspector still leave the failure ambiguous.

Guardrails

investigate before changing retries
codegen output is raw material, not final test code
flake fixes should remove ambiguity, not just slow the test down
CI-only failures usually mean environment or synchronization drift, not just “bad luck”

Avoid

bumping retries first and calling the flake solved
committing codegen output unchanged
adding blanket waits because the trace was not inspected
treating one passing rerun as proof the test is healthy

Read the full file on GitHub · 77 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

references/flake-investigation-defaults.md 530 B

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

2mo ago First seen · 77 lines · 57 tokens per session scan A fc527dda504d

Subscribe to this mod's changes

playwright-debugging-traces-and-flake-reduction is a skill published in the GitHub repository andrewsrigom/agent-skills (2 stars, last pushed 7mo ago), licensed MIT. It adds 57 tokens to every session and 677 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Debugging E2E testing Testing

playwright-debugging-traces-and-flake-reduction next to 6 skills from other repositories
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playwright-debugging-traces-and-flake-reductionandrewsrigom/agent-skills	Skill	2	7mo ago	MIT	A	57	Claude Code, Codex
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