How to Use Claude Code with Opus 5.5 & Fable 5.1 for Free ( No Card Required)

Want to use Claude Code with top models like Claude Opus 5.5 and Fable 5.1, but don't want to pay for a subscription or fund an API account yet?

In this guide, I'll show you how to connect Claude Code to a third-party AI gateway that gives you 500,000 free tokens every month, with no credit card required. The setup takes about five minutes.

⚠️ Before you start: This uses a third-party service that is not affiliated with or endorsed by Anthropic. Free plan limits, available models, and pricing can change at any time. Read the disclaimer at the end before you use it for anything serious.

🎥 Watch the Video Tutorial

Prefer watching? Here's the full step-by-step walkthrough:

What You Get

How much is 500K tokens?

A token is a small chunk of text, often part of a word. A common rule of thumb for English:

• 1 token ≈ 4 characters ≈ ¾ of a word
• 1,000 tokens ≈ 750 words
• 500,000 tokens ≈ 375,000 words Input and output both count. Coding sessions also send file contents and conversation history as context, so a long agentic session uses more than you might expect. Still, 500K a month is plenty for learning and for several small projects.

Why Use Claude Code with Free Tokens?

• Students and beginners can learn AI-assisted coding at zero cost.
• Indie developers can prototype ideas without upfront spend.
• Curious developers can try premium models like Opus 5.5 before committing to a paid plan.

• Content creators and educators can demo Claude Code without burning a personal budget.

  Prerequisites

• A computer running Windows, macOS, or Linux

• An internet connection

• A free account on the AI gateway: Radox AI

• About 5 minutes

  Step-by-Step Setup

Step 1: Install Claude Code

If you don't already have Claude Code installed, follow the official installation guide:

👉 Claude Code documentation

Once it's installed, open it once to make sure it launches correctly.

Step 2: Enable Developer Mode

Developer Mode unlocks the advanced configuration options, including third-party inference. That's what lets Claude Code send requests to a provider other than the default.

1. Open the settings.
2. Find and turn on Developer Mode.
3. Open the third-party inference configuration. > 💡 Menu names can change between versions. If you can't find an option, check the video above or the latest official docs.

Step 3: Add Your API Key and Endpoint

1. Sign up on Radox AI. No card is needed.
2. Open your dashboard and create an API key.
3. Copy the Gateway Base URL (endpoint) from the dashboard.
4. Paste both into the third-party inference settings in Claude Code.

API Key:   <your-api-key>
Endpoint:  <gateway-base-url-from-your-dashboard>

🔐 Treat your API key like a password. Never commit it to Git, paste it in public chats, or show it on screen in recordings.

Step 4: Test, Reload, and Launch

1. Click Test Connection and wait for a success message.
2. Reload and launch Claude Code.
3. Select Claude Opus 5.5 or Fable 5.1 as your model. You're ready to code with free tokens. 🎉

Try It: Your First Prompt

Here's a fun prompt to test the setup. It builds a complete, polished browser game in one shot:

Build a single-file HTML/CSS/JS game called "Orbit Rush". A glowing orb
circles a central star. Tap or press Space to switch between an inner and
outer orbit (with a smooth transition). Meteors fly in from the edges, so
dodge them and collect energy shards for points. Speed ramps up over time.

Visuals matter most: dark space background with parallax stars, neon glow,
a fading comet trail behind the orb, particle bursts on collecting and
crashing, a subtle screen shake on game over, and a polished title screen,
score HUD, and restart button. Add small WebAudio sound effects (no external
files) and save the high score in localStorage. Use canvas, 60fps, responsive
to any screen size, no libraries. Make it feel like a finished game.

Open the generated HTML file in your browser and play. A prompt like this is a good way to see what Opus 5.5 can do with a single request.

Tips to Make Your Free Tokens Last Longer

Every message sends context to the model, so a little care stretches your 500K much further:

1. Start fresh for new tasks. Use /clear when you switch to something unrelated, so old conversation history isn't re-sent.
2. Compact long sessions. Use /compact to summarize a long conversation and cut the context size.
3. Be specific. A clear, detailed prompt avoids back-and-forth that wastes tokens.
4. Point to the exact files. Name the files that matter instead of letting the agent explore your whole repo.
5. Match the model to the task. Save the most powerful models for hard problems, and use lighter ones for simple edits if your gateway offers them.
6. Check your usage. Keep an eye on the token counter in your gateway dashboard so you don't run out mid-project. ## Troubleshooting

Test Connection fails

• Check that the API key was copied fully, with no extra spaces.
• Check that the endpoint URL matches the dashboard exactly, including https://.
• Make sure your free quota hasn't run out for the month. The model isn't listed
• Reload Claude Code after saving the settings.
• Check your gateway dashboard to see which models your plan currently includes. Responses suddenly stop
• You may have hit your monthly limit. Check usage in the dashboard. ## FAQ

Is this really free?
At the time of writing, the gateway offers 500,000 tokens per month with no credit card. Free plans can change at any time, so check the current terms on the site.

Is this official from Anthropic?
No. It's a third-party gateway that Claude Code connects to through its third-party inference support. It isn't affiliated with or endorsed by Anthropic.

Can I use this for work projects?
I wouldn't recommend it for sensitive or proprietary code. Your prompts and code pass through a third-party service. For professional work, use an official plan or the official API.

What happens when I run out of tokens?
Requests will fail until your quota resets next month, or until you switch to another provider or plan.

Disclaimer

This guide is for educational purposes. The gateway used here is a third-party service, not affiliated with Anthropic. Free plan limits, model availability, and terms can change at any time without notice. Always:

• Read the provider's terms and privacy policy
• Keep your API key private
• Avoid sending sensitive, personal, or proprietary data through third-party services ## Wrapping Up

With a few minutes of setup, you can use Claude Code with Opus 5.5 and Fable 5.1 on 500K free tokens a month. That's a great way to learn AI-assisted development, prototype ideas, and try premium models before paying for anything.

If this helped, watch the full video tutorial above and subscribe to The Code Street on YouTube for more indie dev and AI coding content.

💬 Are you using Claude Code yet? Paid plan, API, or free tokens? Tell me in the comments!