Borrowing it
Nothing to install: this file belongs to lootlog/monorepo. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/lootlog/monorepo/main/.agents/skills/engineering-rigor/SKILL.mdgit clone --depth 1 https://github.com/lootlog/monorepoWrote 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/lootlog/monorepo/engineering-rigor)<a href="https://agentmods.dev/skills/lootlog/monorepo/engineering-rigor"><img src="https://agentmods.dev/badge/skills/lootlog/monorepo/engineering-rigor/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/lootlog/monorepo/engineering-rigor"><img src="https://agentmods.dev/badge/skills/lootlog/monorepo/engineering-rigor.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 | $0.00054 | $0.00325 |
| Opus 5.5 | $0.00022 | $0.00130 |
| Sonnet 5.5 | $0.00011 | $0.00065 |
| Haiku 4.5 | $0.00005 | $0.00032 |
Grade A, and why
engineering-rigor 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 1mo 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
Engineering rigor
Make the smallest complete change that reaches the intended architecture.
Shape
- Model the domain in data structures instead of scattered conditions.
- Concentrate parsing, validation, and framework adaptation at system boundaries.
- Prefer deep modules with small interfaces and low reader load.
- Remove dead code and redundant layers before adding abstractions.
- Redesign from the requirement as a first-class constraint instead of bolting on exceptions.
Change
- Migrate every caller and delete the legacy internal API in the same change.
- For internal APIs, migrate callers instead of adding compatibility layers unless the user requests them. Preserve deployed and persisted contracts required by
AGENTS.md, including coordinated rollout where needed. - Delete re-export-only wrappers and import from the owning module.
- Separate concurrent writers before adding locks. When shared state is necessary, make operations idempotent across retries and partial failures.
- Break wide work into verifiable units. Keep every intermediate commit or phase coherent.
Prove
- Reproduce defects before fixing them when practical.
- Verify the real artifact, not only a proxy such as compilation.
- Inspect the diff and generated output.
- Run targeted tests, typecheck, lint, and broader checks in proportion to risk.
Use blast-radius when the main risk lies outside the edited symbols.
What ships with it
1 file 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.
- 1mo ago Changed · -1 lines 6b0d88b0b019
- 1mo ago First seen · 35 lines · 54 tokens per session scan A 61c9e346db19
engineering-rigor is a skill published in the GitHub repository lootlog/monorepo (29 stars, last pushed yesterday), licensed MIT. It adds 54 tokens to every session and 325 once invoked, about $0.0002 per session on Opus 5.5. 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.
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