typescript-advanced-types

A guide to TypeScript's advanced type features, which let you describe and check complicated relationships between values in code. TypeScript is JavaScript with optional checks that catch many mistakes before the program runs.

In plain words
What is it for?
Writing generics, conditional and mapped types, template-literal types, and utility types for compile-time safety.
Why use it?
It helps prevent type mistakes when ordinary type annotations are not enough for a complex application or reusable library.

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/trycompai/evie/typescript-advanced-types
Any agent
npx skills add trycompai/evie --skill typescript-advanced-types
Clone the repo
git clone --depth 1 https://github.com/trycompai/evie

Made for: Claude Code, Codex.

Per session 57 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,063 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin unknown 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 $0.00057 $0.02063
Opus 5 $0.00028 $0.01032
Sonnet 5 $0.00011 $0.00413
Haiku 4.5 $0.00006 $0.00206

Measured 2d ago against content hash c32101c65134, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

typescript-advanced-types 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.

.agents/skills/typescript-advanced-types/SKILL.md · 319 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

Files

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.

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 · 319 lines · 57 tokens per session scan A c32101c65134

Subscribe to this mod's changes

typescript-advanced-types is a skill published in the GitHub repository trycompai/evie (5 stars, last pushed 16d ago), with no licence file. It adds 57 tokens to every session and 2,063 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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