typescript-best-practices SKILL.md skillA
This file is byte-identical to the first copy the registry indexed, one of 3 indexed copies. Same content hash, so the same checks give both the same grade.
typescript-best-practices from backnotprop/pstack is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add backnotprop/pstack/typescript-best-practices@git:20261019.6ddf66aPins git:20261019.6ddf66a in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- backnotprop/pstack
- Path
skills/typescript-best-practices/SKILL.md- Versions recorded
- 4
- Latest version
- git:20261019.6ddf66a, committed Oct 19, 2026
- First version recorded
- May 27, 2026
- Size
- 2,765 bytes
- Repository stars
- 3,337
- License
- MIT
TypeScript best practices. Use when reading or editing any .ts or .tsx file.
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
# TypeScript best practices
Apply the **type-system-discipline** principle skill first.
| Rule | Summary |
|------|---------|
| Discriminated unions | Model variants with a `kind` literal discriminant so impossible states can't be represented. No optional-field bags. |
| Branded types | Brand primitives with `& { readonly __brand: "X" }` so they can't be mixed up. Validate once at the boundary. A brand comes from a verifying type guard (`input is AgentId`), never from `as`. |
| Constructive modeling | Build the shape so the illegal value can't be constructed. `[T, ...T[]]` for non-empty, `[T, T][]` for even length, `start` plus `duration` for a range. Not a runtime guard, not a wish for refinement types. |
| Simplest total type | Keep `T[]` while every operation on it stays total. Strengthen to `NonEmpty<T>` only where the loose type forces `!`, a cast, or a "should never happen" throw. |
| `unknown` over `any` | External data is `unknown`. |
| Schemas before guards | Before hand-writing a property-by-property type guard, use the repository's runtime schema library and infer the type from the schema, such as `z.infer`. |
…Read the whole file at its exact version.
How to install
mdr add backnotprop/pstack/typescript-best-practices@sha256:ec1dac086d3708e5The line at the top of this page pins the label git:20261019.6ddf66a, 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_gve4ymyinrzmncm7)
2 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 4 versions of this file, between May 27, 2026 and Oct 19, 2026, about one every 49 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20261019.6ddf66a latest | 2026-10-19 | 6ddf66a | 2,765 B | A | view · diff |
| git:20260914.55bfdc2 | 2026-09-14 | 55bfdc2 | 2,684 B | A | view · diff |
| git:20260819.4b32d9d | 2026-08-19 | 4b32d9d | 2,444 B | A | view · diff |
| git:20260527.b3eabf1 | 2026-05-27 | b3eabf1 | 1,693 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 (2765 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
backnotprop/pstack · 3,337 stars · license MIT · pushed 2026-10-28 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_gve4ymyinrzmncm7 GET https://markdownregistry.com/api/v1/resolve?ref=backnotprop/pstack/typescript-best-practices GET https://markdownregistry.com/api/v1/blob/ec1dac086d3708e5940d45d250c30a37dd953b4e3cb2ca0692f5851d7a039e27
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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