test-failure-triage

test-failure-triage is a skill for Claude Code from jakesterns/agent-skills. It costs 30 tokens per session (302 once invoked), scanned A, original, MIT.

A method for investigating failed tests and finding whether the cause is a product bug, an outdated expectation, flaky timing, or an environment problem.

In plain words
What is it for?
Use it to analyse test output and CI logs, trace failures to the behaviour they protect, propose the smallest fix, and define verification steps.
Why use it?
It focuses attention on the first meaningful failure and avoids weakening or deleting tests to hide the underlying issue.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the test-failure-triage plugin — 1 skill shipped together

Good fit Use it to analyse test output and CI logs, trace failures to the behaviour they protect, propose the smallest fix, and define verification steps.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/jakesterns/agent-skills/test-failure-triage
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 jakesterns/agent-skills --skill test-failure-triage
Clone the repo
git clone --depth 1 https://github.com/jakesterns/agent-skills

Made for: Claude Code.

Or install test-failure-triage, the plugin that ships this one along with the rest of its 1 skill.

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.

agentmods badge for test-failure-triage

README.md
[![agentmods](https://agentmods.dev/badge/skills/jakesterns/agent-skills/test-failure-triage/github.svg)](https://agentmods.dev/skills/jakesterns/agent-skills/test-failure-triage)
Your own site
<a href="https://agentmods.dev/skills/jakesterns/agent-skills/test-failure-triage"><img src="https://agentmods.dev/badge/skills/jakesterns/agent-skills/test-failure-triage/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.

agentmods 80×15 button for test-failure-triage

Your own site · 80×15
<a href="https://agentmods.dev/skills/jakesterns/agent-skills/test-failure-triage"><img src="https://agentmods.dev/badge/skills/jakesterns/agent-skills/test-failure-triage.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 30 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 302 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00030 $0.00302
Opus 5 $0.00015 $0.00151
Sonnet 5 $0.00006 $0.00060
Haiku 4.5 $0.00003 $0.00030

Measured 9d ago against content hash a15f4f30b762, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

test-failure-triage 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 9d 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.

plugins/test-failure-triage/skills/test-failure-triage/SKILL.md · 42 lines

What it actually says

Test Failure Triage

Use this skill when tests fail locally or in CI and the user needs root cause analysis, not just a quick patch.

Inputs

  • Test output, stack traces, CI logs, failing test names, and recent changes
  • Relevant source files and test files
  • Test command and environment details when available

Steps

  1. Identify the first meaningful failure, ignoring downstream failures caused by setup or earlier errors.
  2. Classify the failure: product regression, test expectation drift, flaky timing, environment issue, fixture/data issue, dependency issue, or infrastructure failure.
  3. Trace the failing assertion back to the behavior it protects.
  4. Compare recent code changes against that behavior.
  5. Recommend the smallest fix that preserves the intended behavior.
  6. If the test is stale, explain why and update the expectation only when the new behavior is intentional.
  7. Provide verification commands and any follow-up tests to prevent recurrence.

Output

Return:

  • Root cause summary
  • Failure classification
  • Minimal fix plan
  • Files likely needing changes
  • Verification commands
  • Flake or environment notes if relevant

Guidelines

  • Do not delete or weaken tests just to make CI pass.
  • Treat intermittent failures as real until evidence shows otherwise.
  • Preserve the diagnostic value of the test suite.
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.

  1. 9d ago First seen · 42 lines · 30 tokens per session scan A a15f4f30b762

Subscribe to this mod's changes

test-failure-triage is a skill published in the GitHub repository jakesterns/agent-skills (2 stars, last pushed 3mo ago), licensed MIT. It adds 30 tokens to every session and 302 once invoked, about $0.0002 per session on Opus 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.

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