ai-engineering-from-scratch-zh is a Chinese-language adaptation of a course that teaches AI engineering by implementing algorithms, tools, and agents from the ground up. It is for learners following a 20-stage path across mathematics, machine learning, agent systems, and production topics, with lessons using Python, TypeScript, Rust, and Julia. The catalogue entries provide agent skills and instructions associated with the course.
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 fancyboi999/ai-engineering-from-scratch-zh --skill skill-contract-reviewergit clone --depth 1 https://github.com/fancyboi999/ai-engineering-from-scratch-zhWrote 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/fancyboi999/ai-engineering-from-scratch-zh/skill-contract-reviewer)<a href="https://agentmods.dev/skills/fancyboi999/ai-engineering-from-scratch-zh/skill-contract-reviewer"><img src="https://agentmods.dev/badge/skills/fancyboi999/ai-engineering-from-scratch-zh/skill-contract-reviewer/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/fancyboi999/ai-engineering-from-scratch-zh/skill-contract-reviewer"><img src="https://agentmods.dev/badge/skills/fancyboi999/ai-engineering-from-scratch-zh/skill-contract-reviewer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00024 | $0.00411 |
| Opus 5 | $0.00012 | $0.00205 |
| Sonnet 5 | $0.00005 | $0.00082 |
| Haiku 4.5 | $0.00002 | $0.00041 |
Grade A, and why
skill-contract-reviewer 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 8d 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.
What it actually says
Skill 契约审查器
当工作流即将成为可复用的 agent 产物时，使用此 skill。
- 将
SKILL_ROOT设为包含本已安装SKILL.md的绝对目录。不要假定进程工作目录就是 Bundle。 - 将
TARGET_ROOT设为原始工作区的绝对工作目录，并在该根目录下解析候选 skill 目录。 - 读取
$SKILL_ROOT/references/contract.md，验证可移植SKILL.md的标识字段。 - 读取
$SKILL_ROOT/references/decision-model.md，区分仓库上下文、可复用方法、外部能力、生命周期时机、确定性逻辑和隔离委派。 - 执行前展示精确解析后的参数向量。运行
python3 "$SKILL_ROOT/scripts/check_skill.py" "$TARGET_SKILL"，其中TARGET_SKILL是TARGET_ROOT下候选 skill 的绝对目录。 - 检查 JSON 报告。讨论 host 专属扩展前，修复全部错误。
- 将候选产物与
$SKILL_ROOT/assets/task-shapes.json比较，返回最小可组合原语集合。
不要声称运行时扩展属于可移植契约。不要将有效 skill 视作运行脚本或访问工具的权限。
返回验证报告、所选原语和解释每项选择的一句话。附上执行证据：解析后的脚本路径、目标路径、cwd、精确 argv 与退出码。若 host 无法暴露其中某项观察，将其标为未验证，不要虚构。
What ships with it
4 files 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.
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.
- 8d ago First seen · 24 lines · 24 tokens per session scan A 36d02c5b43cf
skill-contract-reviewer is a skill published in the GitHub repository fancyboi999/ai-engineering-from-scratch-zh (1,056 stars, last pushed 4d ago), licensed MIT. It adds 24 tokens to every session and 411 once invoked, about $0.0001 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 2026-09-03.
Other skills, from other repositories
skill-release-gate
Evaluate an Agent Skill bundle for structural integrity, trigger quality, artifact improvement, script correctness, safety, installed-tree integrity, and target-host portability before release.
skill-contract-reviewer
Validate an Agent Skill package and choose the right instruction, capability, or lifecycle primitive before implementation.
skill-invocation-router
Design and test explicit human, implicit model or agent, programmatic application, bounded skill-composition, and harness activation policies for an Agent Skill catalog.
migration-review
Review database migration files when a change adds or modifies paths under migrations/. Use it before merge to collect forward, rollback, locking, and data-safety evidence.
skill-catalog-builder
Build a bounded Agent Skill catalog across explicit discovery scopes and report collisions before loading instruction bodies.
skill-safety-reviewer
Review a skill-requested filesystem, command, network, secret, or destructive action against an explicit sandbox policy without executing it.