Diagnoses a failure with parallel rival-hypothesis testing — multiple read-only subagents test distinct explanations in parallel, then rank by evidence weight while keeping losing rivals visible so the root cause is found honestly, not just plausibly. Make sure to use this skill whenever the user reports something broken with an unclear cause — "tests fail", "test is failing", "X doesn't work", "Y crashes", "why is Z happening", "investigate this bug", "what's causing this", "the bug is unclear", "something's wrong with X", "X used to work and now doesn't", "this is flaky" — or any failure report where the next diagnostic step isn't already obvious to the user. NOT for feature requests (use h-frame). NOT for performance work with a known bottleneck (use h-frame). NOT for verifying a hypothesis already recorded in a DecisionRecord (use h-verify).
How to install h-diagnose?
m0n0x41d/haft/h-diagnose
$npx -y skills add m0n0x41d/haft --skill h-diagnoseInstalls into the current project.
›Prefer a prompt? Paste this to your agent
Run `npx skills use "https://github.com/m0n0x41d/haft" --skill "m0n0x41d/haft/h-diagnose"` and follow the generated skill instructions now. Read its complete output, redirecting it to a temporary file first if necessary. Resolve relative paths from the supporting-files directory it provides.
Use the skills in "https://github.com/m0n0x41d/haft" that are relevant to the current task. Run `npx skills add "https://github.com/m0n0x41d/haft"` and select the relevant skills, then follow their instructions.
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