Is Kit plugin for Codex
Build small guards. Compose them. A lightweight, zero-dependency toolkit for building reusable TypeScript type guards that compose, refine, and preserve natural narrowing. Runtime-safe 🛡️, composable 🧩, and ergonomic ✨.
How to install Is Kit in Codex
1. Add the repo as a Codex plugin marketplace:
codex plugin marketplace add nyaomaru/is-kit2. Install the plugin from it:
codex plugin add is-kit@is-kitThis repo ships a Codex marketplace file (.agents/plugins/marketplace.json). The first command adds it as a marketplace (Codex CLI reference); the second installs the plugin 'is-kit'. 'is-kit' is the marketplace name from that file. Check the repo README too. Command format: Codex CLI reference.
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What it contains
Plugins in this marketplace (1)
is-kit— Build and migrate composable TypeScript runtime type guards with is-kit.
About this listing
Is Kit is a community plugin on GitHub by nyaomaru. Its README documents a Codex install and the repo ships a Codex plugin manifest. It passed the CodexStacks quality filter for repos found this way (at least 100 stars, pushed in the last 90 days, not a fork or a list). OpenAI hasn't reviewed it, but it passed our Codex install check on Oct 28, 2026 (an install and load check, not a code review). From its files we found 1 plugin. It's one of 441 listings in the Developer Tools category.
Is Kit FAQ
How do I install Is Kit in Codex?
Add the repo as a Codex plugin marketplace with codex plugin marketplace add nyaomaru/is-kit, then install it with codex plugin add is-kit@is-kit. Commands: the command format from the Codex CLI reference; check the repo README too.
Is Is Kit an official Codex plugin?
No. Is Kit is a community repo on GitHub by nyaomaru. It passed the CodexStacks quality filter, but OpenAI hasn't reviewed it, but it passed our Codex install check on Oct 28, 2026 (an install and load check, not a code review), so read the code before you install it.
What does Is Kit include?
From its manifest and repo files, Is Kit includes 1 plugin: is-kit.
Details
- Type
- Plugin
- Category
- Developer Tools
- Source
- Community
- Author
- nyaomaru
- License
- MIT
- GitHub stars
- 143 (at last sync)
- Last push
- 2026-10-27
- Manifest
.agents/plugins/marketplace.json- GitHub topics
- is, open-source, runtime-type-checking, type-guard, type-guards, type-safe, typescript, utility, validation
- Source
- https://github.com/nyaomaru/is-kit
- Website
- https://is-kit.dev
- Listed via
- GitHub search: README documents a Codex install
- Install check by CodexStacks
- Passed on Oct 28, 2026 with Codex CLI 0.163.0: Codex loaded its skills. proof · how we check
Something wrong or missing? Submit or improve this listing. Listings also refresh automatically every night.
For maintainers: badge and embeds
Maintain Is Kit? Add the badge; it links to this page.
Markdown
[](https://codexstacks.com/p/is-kit/)HTML
<a href="https://codexstacks.com/p/is-kit/"><img src="https://codexstacks.com/badge.svg" alt="Listed on CodexStacks" width="172" height="28"></a>Embed card (static HTML and inline CSS, no JavaScript). Preview:
<a href="https://codexstacks.com/p/is-kit/" style="display:block;max-width:380px;box-sizing:border-box;padding:14px 16px;border:1px solid #3a2c26;border-radius:12px;background:#0d0b0a;color:#f3ece6;font:14px/1.45 -apple-system,Segoe UI,Roboto,Helvetica,Arial,sans-serif;text-decoration:none"><span style="display:block;font-size:16px;font-weight:700;color:#f3ece6">Is Kit</span><span style="display:block;margin:2px 0 8px;font-size:12px;color:#b5a9a1">Community Codex plugin · 1 plugin</span><span style="display:block;margin:0 0 10px;color:#ddd3cc">Build small guards. Compose them. A lightweight, zero-dependency toolkit for building reusable TypeScript type guards…</span><span style="font-size:12px;font-weight:600;color:#ffb347">View on CodexStacks →</span></a>Markdown summary
**[Is Kit on CodexStacks](https://codexstacks.com/p/is-kit/)**: Community Codex plugin with 1 plugin.More on badges, embeds and keeping your listing up to date: CodexStacks for plugin authors.
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