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.
npx skills add mehdiforoozandeh/crux --skill evolve-cruxgit clone --depth 1 https://github.com/mehdiforoozandeh/cruxWrote 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.
[](https://agentmods.dev/skills/mehdiforoozandeh/crux/evolve-crux)<a href="https://agentmods.dev/skills/mehdiforoozandeh/crux/evolve-crux"><img src="https://agentmods.dev/badge/skills/mehdiforoozandeh/crux/evolve-crux/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.
<a href="https://agentmods.dev/skills/mehdiforoozandeh/crux/evolve-crux"><img src="https://agentmods.dev/badge/skills/mehdiforoozandeh/crux/evolve-crux.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00218 | $0.02665 |
| Opus 5 | $0.00109 | $0.01333 |
| Sonnet 5 | $0.00044 | $0.00533 |
| Haiku 4.5 | $0.00022 | $0.00266 |
Grade A, and why
evolve-crux 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 12d 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.
How it starts
The opening of the file, as written. The whole thing — 191 lines — stays where its author put it; the contents beside it link to each section on GitHub.
evolve-crux — ship a change to crux, rigorously
This skill is for working on crux the tool (your clone of the crux repo), not on a research project that uses crux. It carries one change — a new capability or a fix for something crux keeps getting wrong — through a strictly gated arc:
ideate → build → validate → ship
Each stage has an exit criterion; you do not advance until it's met. The arc is the
same whether the change is a one-line bug fix or a .spec/ epic — only the ceremony scales.
Who's driving (contributor-always)
Assume the person evolving crux is not the maintainer. Because crux ships this skill to its users, everyone runs the same path and ends at a pull request — no auto-detection of who you are, no privileged branch. The maintainer is just the contributor who can self-merge their own PR, plus a small, separate release step (below). This keeps one code path and makes third-party PRs first-class.
Work in a dedicated session inside your crux clone (a fresh chat, not the project you
were researching). No clone yet — e.g. you installed the skills via npx skills add?
git clone https://github.com/mehdiforoozandeh/crux first. For a large build you may
dispatch a worktree sub-agent, but the default is the main thread.
1 · Ideate → a signed-off PRD ◆
Ideation ends when there is a PRD the human has approved — not before any code. Reach
it by a pingpong / grill-me back-and-forth (surface one decision at a time; don't dump
options): what exactly are we adding or fixing, why, the design choice, and — load-bearing
— the acceptance criteria (the concrete checks that later become the validation
gate). Pre-registering "how we'll know it worked" is what makes validate enforceable
instead of vibes.
The PRD scales to the change:
- Bug ("crux keeps mis-splitting inline parens") → a one-line PRD: the wrong behavior, the correct behavior, and the acceptance criterion = a failing selftest that asserts the correct behavior.
- Feature / backlog epic (UI, wiki, autoresearch) → a full grilled PRD (skeleton below).
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.
- 12d ago First seen · 191 lines · 218 tokens per session scan A d22b45761a37
evolve-crux is a skill published in the GitHub repository mehdiforoozandeh/crux (6 stars, last pushed 7d ago), licensed MIT. It adds 218 tokens to every session and 2,665 once invoked, about $0.0011 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.
Other skills, from other repositories
ab-testing
Use when designing or analyzing a controlled experiment — falsifiable hypothesis, sample size from an MDE, reading significance/CI/power, CUPED, or rescuing tests that won't go significant. NOT recurring metric tracking (that is analytics), NOT north-star/KPI trees (that is kpi-framework), NOT projecting metrics…
product-principles
Defines 4 Risks confidence thresholds, OST hierarchy levels, Knowledge Pyramid tiers, and state design requirements. Use when evaluating user stories, setting confidence scores, referencing OST levels, scoping MVP, or determining validation sufficiency.
recipe-define
Orchestrate PRD creation from validated hypotheses — standard PRD output with 4 Risks confidence and hypothesis traceability.
recipe-validate
Orchestrate hypothesis validation through type-appropriate methods — prototypes, code analysis, market research, and expert review.
hypothesis-discipline
Manages hypothesis lifecycle, enforces validation criteria, time budgets, and confidence scoring rules. Use when creating hypotheses, updating confidence scores, setting validation criteria, handling timeouts, or recording validation results.
blueprint-standards
Defines structural design artifact formats — information architecture, user flows, content model, brand direction, and AI interaction model. Use when creating or reviewing structural design documents that precede prototype generation.