typescript-development

A working guide for building and maintaining TypeScript software, including applications, libraries, services, and development tools. TypeScript is JavaScript with optional compile-time checks.

In plain words
What is it for?
Use it for TypeScript code, Node.js services, configuration, packages, API clients, asynchronous code, testing, and publishing.
Why use it?
It helps keep types accurate, validate outside data, and verify that the real project still builds and passes its tests.

Skill for Claude CodeCodex

Install

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.

agentmods
npx agentmods add skills/code-saurabh/openskills/typescript-development
Any agent
npx skills add CODE-SAURABH/OpenSkills --skill typescript-development
Clone the repo
git clone --depth 1 https://github.com/CODE-SAURABH/OpenSkills

Made for: Claude Code, Codex.

Per session 58 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,294 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.00058 $0.03294
Opus 5 $0.00029 $0.01647
Sonnet 5 $0.00012 $0.00659
Haiku 4.5 $0.00006 $0.00329

Measured 2d ago against content hash c7fd852f609d, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

typescript-development 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.

typescript-development/SKILL.md · 284 lines

How it starts

The opening of the file, as written. The whole thing — 284 lines — stays where its author put it; the contents beside it link to each section on GitHub.

TypeScript Development

Act as the TypeScript engineer who treats the type system as a design tool, not syntax layered over unvalidated JavaScript. Deliver code that is type-safe at compile time, validated at runtime, secure at process boundaries, and compatible with the existing toolchain.

Execution Workflow

  1. Inspect the contract. Read package.json, lockfile, tsconfig, workspace configuration, scripts, runtime target, module system, test runner, and local conventions. Use the checked-in package manager.
  2. Model the domain. Identify trusted and untrusted data, public API compatibility, errors, and lifecycle constraints. Define narrow types before implementation.
  3. Implement without escapes. Parse at boundaries, keep effects explicit, and separate domain logic from transport, persistence, and framework code.
  4. Verify the real artifact. Run type checking, linting, unit tests, build/bundle checks, and targeted integration tests supported by the project.
  5. Hand off operationally. State behavior changes, API/schema effects, commands run, and remaining risks.

Step 0: Establish Evidence and Scope

Before code, identify the requested observable behavior, affected package(s), runtime target, public consumers, untrusted inputs, side effects, and validation command. Inspect package.json, lockfile, workspace files, tsconfig, test configuration, build configuration, CI, and nearby code. Never infer that a package, alias, compiler flag, or Node version exists because it is common elsewhere.

For a change that affects an API, event, stored data, environment variable, package export, or shared type, state the compatibility decision explicitly: additive, backward-compatible migration, or intentional breaking change.

Implementation Plan Template

## TypeScript Change Plan

**Objective:** <observable behavior>
**Packages / runtime:** <affected workspace and browser/node/edge target>
**Boundary inputs:** <HTTP, env, queue, JSON, storage, file>
**Runtime validation:** <schema/guard and error result>
**Types and compatibility:** <new/changed exports and consumers>
**Effects:** <database, network, filesystem, queue>
**Verification:** <typecheck, tests, build, consumer test>

Read the full file on GitHub · 284 lines

Changes

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.

  1. 2d ago First seen · 284 lines · 58 tokens per session scan A c7fd852f609d

Subscribe to this mod's changes

typescript-development is a skill published in the GitHub repository CODE-SAURABH/OpenSkills (2 stars, last pushed 1mo ago), licensed MIT. It adds 58 tokens to every session and 3,294 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 2026-08-31.

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