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The canonical benchmark

New models ship constantly. The question that matters isn’t “what’s the leaderboard say?” — it’s “which one is better at my decisions?” Prevail’s canonical benchmark answers that with a fixed question suite you run against any CLI, model, or council configuration.

The bundled suite is 21 questions across 8 capability dimensions — the kinds of reasoning personal decisions actually demand:

DimensionWhat it probes
Document analysisReading a P&L, a lab panel, or a contract and pulling the signal
RecencyWhether the model knows about recent changes, or bluffs past its cutoff
Cultural literacyNuance around family, obligation, and context
BrevityWhether it can answer in one disciplined sentence when asked
Bias resistanceRejecting an anchored or leading frame
Insufficient-info recognitionRefusing to recommend when it lacks the facts
Tax trapsCatching rules that trip up most models (e.g. passive-loss exceptions)
Decision disciplineCommitting to a recommendation under uncertainty

Some questions are deliberately adversarial — the passive-loss trap, for instance, is one that the majority of LLMs answer wrong.

Each question is a markdown file with the prompt, an expected decision, and scoring hints:

---
id: tax-passive-loss-trap
domain: tax
dimension: tax-traps
expected_verdict_keywords: ["material participation", "§469", "cannot deduct"]
---
## Question
I have a $40k passive loss from a rental K-1 and $200k of W-2 wages.
Can I deduct the loss against my wages this year?
## Expected decision
No — passive losses can't offset active income unless you materially
participate or qualify as a real-estate professional. The loss carries forward.

Questions can carry attachments (a P&L statement, a lab panel, a contract draft) that get inlined into the prompt up to a per-question character budget, so the model is reasoning over realistic source material rather than a toy summary.

<vault>/benchmark/
├── README.md the capability matrix + instructions
├── questions/ canonical questions, grouped by domain
├── attachments/ source documents inlined into prompts
└── runs/ results, one folder per (date, cli, model)

The bundled suite is a starting point. The real value is grading models against your recurring decisions:

Terminal window
prevail bench seed --domain wealth write a stub question to fill in
prevail bench seed --from-log wealth turn a recent council verdict into a draft question

--from-log is the clever one: take a verdict you trust, freeze it as ground truth, and now every future model gets graded on whether it reaches the same conclusion.