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 agentmods add skills/aayushostwal/nexus/testingnpx skills add aayushostwal/nexus --skill testinggit clone --depth 1 https://github.com/aayushostwal/nexusWhat 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 | $0.00069 | $0.01974 |
| Opus 5 | $0.00034 | $0.00987 |
| Sonnet 5 | $0.00014 | $0.00395 |
| Haiku 4.5 | $0.00007 | $0.00197 |
Grade A, and why
nexus-testing 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 2d 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 — 197 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Nexus Flaky Test Root Cause Analyzer
Structured protocol for diagnosing, isolating, and permanently eliminating non-deterministic test failures. Not a retry wrapper — treats flakiness as a first-class defect.
name: nexus-testing
category: testing / quality
required_context: test file path, failure frequency, CI log or local output, stack trace if available
expected_inputs: test name, framework, failure pattern, environment (local/CI/both), reproduction rate
expected_outputs: flakiness type, reproduction steps, root cause (one sentence), narrowest fix +
verification command, prevention recommendation
Core Principles
- A test failing 1-in-20 runs is still failing — it is a false alarm factory.
- A retry without investigation ships unknown risk.
- Fix the root cause, not the symptom — masking a race condition makes it fail more often.
- Never mark
xfail/skipwithout a linked issue and expiry date. - Test flakiness often mirrors a real production concurrency or data integrity hazard.
Step 1 — Collect Context
Required before any investigation:
| Signal | How |
|---|---|
| Failure rate | Estimate from CI history (1/5? 1/100?) |
| Stack trace | Full verbatim trace from a failing run |
| Test path | Exact: tests/users/test_create.py::test_create_user |
| Framework + version | pytest --version, jest --version, go version |
| CI vs local | Fails only in CI, only locally, or both? |
| Parallelism config | -n auto, --workers, t.Parallel()? |
| Recent changes | git log --oneline -10 on test file and its imports |
If CI-only failure, diff these before reading code: runtime version, OS/arch, parallelism,
TZ / NTP, network access, env vars (missing vars silently produce defaults), I/O speed, Docker layer cache.
Step 2 — Classify Flakiness Type
| Type | Signature | Mechanism |
|---|---|---|
| Ordering | Fails after specific other tests; passes alone | Shared mutable state not reset |
| Timing | Fails on slow machines or under load | Hard-coded delays, no backoff, wall-clock assertions |
| Resource | Fails parallel, passes single-threaded | Port conflicts, shared temp dirs, DB row locks |
| Environment | Fails in CI only | Runtime delta, missing env var, OS behavior |
| External | Network errors, connection refused, timeouts | Real HTTP/DB calls in test |
| Concurrency | Assertion error varies each run; stack trace differs | Thread/async race, missing lock |
What ships with it
2 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.
- 2d ago First seen · 197 lines · 69 tokens per session scan A 583630d3c3df
nexus-testing is a skill published in the GitHub repository aayushostwal/nexus (18 stars, last pushed 23d ago), licensed MIT. It adds 69 tokens to every session and 1,974 once invoked, about $0.0003 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 2026-08-30.
Other skills, from other repositories
productize-yourself
当用户在纠结职业/副业/自由职业方向、问「我该做什么才能赚钱/不被替代」、或想找到自己的独特优势时调用。 核心理念: 特殊知识(不可培训、对你像玩对别人像工作) × 产品化(杠杆规模化) = 无可替代的致富定位。 不适用于: 纯求职投递、写简历、已有明确方向的执行细节。 Triggers: 找方向/独特优势/副业/不可替代/productize/special knowledge/moat.
screen-detox
当用户刷手机/短视频/社交媒体上瘾、感觉空虚、想戒断多巴胺零食时调用。 核心理念: 所有屏幕活动与更少幸福相关(作者断言无例外); 屏幕=用长期后果换短期快感的多巴胺零食; 用习惯替换五步戒断。 不适用于: 工作需要屏幕的职业场景(区分工作屏幕与消费屏幕)。 Triggers: 刷手机/上瘾/短视频/社交媒体/多巴胺/戒断/屏幕时间/screen time/dopamine/addiction.
happiness-skill
当用户问「怎么才能更幸福/为什么得到了还不满足/怎么减少焦虑」时调用。 核心理念: 幸福是缺憾感清空的默认状态, 是可训练的技能; 欲望是与自己的契约(得到前不快乐), 同时只留一个重大欲望; 活在当下。 不适用于: 临床抑郁等需要专业治疗的场景(本书方法不能替代医疗)。 Triggers: 幸福/不快乐/欲望/焦虑/知足/活在当下/happiness/desire/anxiety.
long-term-compounding
当用户在选择合作者/生意模式/人生策略、问「要不要长期投入这段关系/这个项目」「如何积累声誉」时调用。 核心理念: 财富、知识、声誉、关系都遵循复利; 只玩长期正和游戏, 与能想象共事一辈子的人合作, 拒绝短期思维交易。 不适用于: 紧急止损、短期现金周转等必须立即决策的场景。 Triggers: 长期/复利/声誉/合作/信任/compounding/long-term/trust.
monkey-mind-meditation
当用户脑子停不下来、焦虑反刍、想学冥想/提升专注力时调用。 核心理念: 内心独白(心猴)是失控程序不是"我"; 用调试模式逐条观察念头, 意识到即失去控制; 冥想=收件箱归零/心灵间歇性禁食。 不适用于: 严重精神疾病急性发作(先就医); 需要立刻处理的实际问题(先做事)。 Triggers: 冥想/焦虑/脑子停不下来/胡思乱想/专注/心猴/monkey mind/meditation/anxiety.
hook-craft
Specializes in chapter openings (hooks) and chapter endings (pulls). Every chapter must start with a reason to keep reading and end with a reason to turn the page. Runs after prose-craft, before chaos-engine. The skill that prevents the reader from putting the book down.