engineering-principles SKILL.md skillA
engineering-principles from damianvtran/local-operator is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add damianvtran/local-operator/engineering-principles@git:20261012.3e10f8ePins git:20261012.3e10f8e in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- damianvtran/local-operator
- Path
local_operator/skills/builtin/engineering-principles/SKILL.md- Versions recorded
- 2
- Latest version
- git:20261012.3e10f8e, committed Oct 12, 2026
- First version recorded
- Oct 10, 2026
- Size
- 2,978 bytes
- Repository stars
- 218
- License
- MIT
Practical engineering judgement: smallest change, subtract before adding, data structures before logic, idempotent operations, migrate callers then delete. Use when designing, building, or reviewing changes.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Engineering principles Judgement for building changes. One rule per line; the third column is what breaking it looks like. | Principle | In practice | Violated by | |---|---|---| | Laziness protocol | Do not build what nothing needs yet. | Speculative abstraction, config for a case nobody has | | Smallest change | The best change leaves the least to review, test, and revert. | Drive-by refactors mixed into a fix | | Subtract before adding | Delete a concept before you add one; every new layer is paid for forever. | A new wrapper around an old wrapper | | Data structures before logic | Get the shape of the data right and the code collapses into simple reads. | Nested conditionals over a badly shaped object | | Boundary discipline | Validate at the edges (user input, network, files); trust the interior. | Re-validating everywhere, or validating nowhere | | Type system discipline | Make illegal states unrepresentable where the language allows it. | Runtime flags that contradict each other | | Idempotency | Running it twice is as safe as running it once. | Operations that double-charge, double-post, or duplicate | …
Read the whole file at its exact version.
How to install
mdr add damianvtran/local-operator/engineering-principles@sha256:b9053a3f19993d9dThe line at the top of this page pins the label git:20261012.3e10f8e, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_jrqgl7cnunrfuanj)
2 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 2 versions of this file, between Oct 10, 2026 and Oct 12, 2026, about one every 2 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20261012.3e10f8e latest | 2026-10-12 | 3e10f8e | 2,978 B | A | view · diff |
| git:20261010.ee06e2b | 2026-10-10 | ee06e2b | 2,477 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (2978 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
damianvtran/local-operator · 218 stars · license MIT · pushed 2026-10-20 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_jrqgl7cnunrfuanj GET https://markdownregistry.com/api/v1/resolve?ref=damianvtran/local-operator/engineering-principles GET https://markdownregistry.com/api/v1/blob/b9053a3f19993d9d5e9d46f02994c6629f2ed095127fbf9259ac37037067d9f0
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.
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