Jev Integration with Claude Code & Codex: A Step-by-Step Guide to Supercharge Your Coding Agent’s Decision-Making!

Hello everyone, I’m Xiao Ma Ge.

Yesterday, I shared how newcomers can quickly get started with Jev:

Xiao Ma Ge@xmglab·Sep 20 Article What exactly is the viral Jev? A beginner’s guide to getting started from scratch—step-by-step tutorial to quickly try it out! Hello everyone, I’m Xiao Ma Ge.
The Jev model has recently gained a lot of attention. Unlike traditional LLMs such as ChatGPT and Claude, Jev is quite different.
Jev was released on September 15, 2026, as the first System One model by TypeSafe… 631226413K

Jev is now open to everyone—no more waitlist, just sign up and start using it right away. The speed of this rollout is truly impressive.

Click here to start using it:

https://console.typesafe.ai

All new users currently receive an initial credit of 5 USD, which the official documentation says is enough for approximately 1.2 billion tokens. There’s no recharge option yet, but it may become available later.

Today, I’ll show you how to use Jev with Claude Code, Codex, and other Coding Agents. If you don’t have time to read now, feel free to bookmark this guide.

Obtain an API Key

Go to the API keys page to create an API Key:

https://console.typesafe.ai/keys

After obtaining the API Key, save it securely and set up a TYPESAFE_API_KEY environment variable locally. You can use it directly in AI tools later without worrying about leaks.

Jev Model Pricing

Jev is not free, but it’s incredibly affordable—costing 40 to 400 times less than other models. Output-side usage is currently free.

Test with curl

You can send a request directly:

curl -X POST https://api.typesafe.ai/v1/systemone \
-H "Authorization: Bearer $TYPESAFE_API_KEY" \
-H "Content-Type: application/json" \
-d @- <<'EOF'
{
  "state": "My Claude account got banned and hasn’t been unbanned. I can’t use it. Could you help me check?",
  "model": "jev-latest",
  "questions": {
    "urgency": {
      "type": "noul",
      "instructions": "Is this issue related to login?"
    }
  }
}
EOF

Test output result:

Use Jev in Coding Agents

Jev provides a plug-and-play Skill:

https://github.com/typesafe-ai/skills

It offers complete context for the TypeSafe API:

• Three types of questions
• Architectural patterns
• Best practices for organizational assessments

This Skill can be used with Claude Code, Codex, and other Coding Agent tools.

Using Jev in Claude Code

Install the Skill

Run the following two commands in your terminal to install:

claude plugin marketplace add typesafe-ai/skills
claude plugin install typesafe@typesafe-ai

Using Jev

Those familiar with Skills know you can simply say “Use TypeSafe skill…” to trigger it, or use the slash command “/typesafe:typesafe-ai” to invoke the TypeSafe Skill directly.

Here’s an example:

/typesafe:typesafe-ai Is it worth buying a Mac mini right now? Give me a direct judgment.

It returns a result in 12 seconds, advising against buying a Mac mini currently.

/typesafe:typesafe-ai Analyze this project and identify replaceable complex logic or weak code.

The output includes a TypeSafe section, indicating which code needs to be removed, retained, or extracted into shared components. TypeSafe provides the judgment here.

Update the Skill

This applies only to plugins installed via the Claude Code marketplace:

claude plugin marketplace update typesafe-ai
claude plugin update typesafe@typesafe-ai

Restart Claude Code or run /reload-plugins to load updates.

To enable auto-updates, open /plugin, then go to Marketplaces → typesafe-ai → enable auto-updates.

Using Jev in Codex and Other Tools

Install the Skill

Run the following installation command in your terminal:

npx skills add typesafe-ai/skills --skill typesafe-ai

By default, it includes mainstream Coding Agents such as Codex, Cursor, Gemini CLI, OpenCode. You can customize other selections below. Press Enter to complete the installation.

Using Jev

Similarly, in Codex, you use Jev just like any Skill. Type “/Typesafe” and it will auto-suggest:

Watch the video demo:

Update the Skill

If you installed via skills.sh, run:

npx skills update

If you manually copied the Skill, replace the entire skill directory with the latest version from GitHub.

Automatic Installation via Prompt

You can also use a prompt to install automatically:

Install the TypeSafe skill. If you are in Claude Code, run claude plugin marketplace add typesafe-ai/skills, then run claude plugin install typesafe@typesafe-ai. If you are in another Coding Agent, run npx skills add typesafe-ai/skills --skill typesafe-ai and select your Coding Agent. Use one of these installation methods. You can read the skill documentation here: https://github.com/typesafe-ai/skills/blob/main/skills/typesafe-ai/SKILL.md (original: https://raw.githubusercontent.com/typesafe-ai/skills/main/skills/typesafe-ai/SKILL.md). After installation, you can use the TypeSafe skill while developing this project.

Paste this into any Skills-supported Coding Agent, and it will automatically install based on the current environment.

That’s all for today’s Jev sharing.

After testing it out, the most interesting thing about Jev is that it offers a completely different way of working. It doesn’t generate content—it focuses more on helping you with judgment, analysis, and decision-making.

So I believe the best way to use Jev is not alone, but in combination with Coding Agents like Claude Code or Codex—Claude Code/Codex handles the execution, while Jev handles the judgment.

Plus, since the official Skill is already provided, there’s no need to manually wrap APIs. Once installed, you can call it directly within your Coding Agent.

Currently, new users still have 5 USD credit, about 1.2 billion tokens, and Jev itself is very affordable—perfect for extensive testing.

Today I only demonstrated basic Jev applications, but it has several killer use cases. I’ll share more in the future and continue testing Jev’s performance in real-world projects, code refactoring, and complex technical decisions.

If you find this helpful, please follow—I’ll be sharing more hardcore insights.

I’m Xiao Ma Ge. See you next time.