Halbrook Docs

1What is Halbrook

Halbrook is an exchange for AI tokens: one wallet, one balance, every major model. You hold tokens of a model, swap them for another at the live price, and spend them in a chat that sends each question to the cheapest host.

Prices are real and public. They come from the hosts themselves and refresh every 60 seconds.

Models available today: Claude Opus 5.5, Claude Fable 5.2, GPT-6 Astra, Gemini 4 Carbon, Mistral Large 4 and DeepSeek V4 Pro.

2Getting started

You need a browser wallet such as MetaMask or Rabby. It takes under a minute.

1. Open the Exchange.
2. Click Connect wallet and accept in your wallet.
3. Click Sign in and sign the message. It is free: no transaction, no gas.
4. Your balance appears at the top of the Exchange.
5. While Halbrook is in test mode, click Get $2 test credit once. You receive 2,000,000 Mistral Large 4 tokens.

You stay signed in for 7 days on that browser.

3Swap tokens between models

A swap turns tokens of one model into tokens of another, at the market price, in one click.

1. Enter an amount in millions of tokens (1 = 1,000,000).
2. Pick the model you give and the model you get.
3. Check what you will receive, then click Swap.

Each model has two prices:

• Reference: the real cost of using the model, from the hosts. It refreshes every 60 seconds.
• Market: what the model trades at on Halbrook. Swaps into a model push it up, swaps out push it down.

The gap between the two is the premium. It always stays between −30% and +30% of the reference, and it fades back toward zero when nobody trades (it halves every 24 hours). Buy a model before the hype, swap out when its premium is high.

Using your tokens, in the chat or through the API, always counts them at the reference price. So a model trading below its reference is a bargain to use: that is its floor.

Big swaps move the premium more, and you pay the average price along the way. Before you confirm, the Exchange shows the premium after your swap. Fee: 0.3%.

The market table lists each model's reference price, market price, premium and cheapest host. Click a row to see where it sits in the band and every host with its price.

4Chat with your tokens

Each question goes to the cheapest host for that model, and you pay only what it really cost.

1. Open the Chat tab.
2. Pick a model you hold tokens in.
3. Type your question and press Enter.

Under each answer: the model that wrote it, the tokens used, the price in dollars, the host it went to, and the saving against the official price. You need at least 2,000 tokens of a model to send a message.

One conversation, every model. Switch models in the middle of a conversation: the new model sees everything said before. New chat starts fresh.

Shared memory. Click Memory to save short notes about you or your work (“I write Python”, “my startup sells to dentists”). Every model reads them, so you never repeat yourself. Notes are encrypted on our server; Forget everything deletes them for good.

5API key

Use your Halbrook balance in any app that works with OpenAI: Cursor, scripts, agents. Same tokens, same cheapest-host routing as the chat.

1. Sign in on the Exchange.
2. Click API key in your balance, then Create a key.
3. Copy it right away: it is shown only once.
4. In your app, set the base URL and the key.

Base URL   https://www.halbrook.xyz/v1
API key    hb_…

curl https://www.halbrook.xyz/v1/chat/completions \
  -H "Authorization: Bearer hb_…" \
  -d '{"model":"claude-opus-5.5","messages":[{"role":"user","content":"Hello"}]}'

Each request is paid from your tokens of the model you call. Before the request, Halbrook sets aside the most it could cost; after the answer, you pay the real cost and the rest comes back. Streaming works. GET /v1/models lists the models and their prices.

Add the header X-Halbrook-Memory: on to give the model your shared memory notes, the same ones as in the chat.

Limits: 60 requests a minute per key, 4 at a time per account, 5 keys per account. Lost a key? Revoke it in one click and create a new one.

6Fees and pricing

A model's price mixes its input and output prices, three parts input for one part output, like a typical conversation.

7The film and the briefcase

The home page is a short interactive film. Solve it once and the Exchange opens for good on that browser.

1. Click the van to open the door.
2. Meet Madame Vale and Horace, her parrot. Look around and talk to them.
3. Find the four-digit code that opens the briefcase.
4. Watch the ending, then click Enter dApp.

Stuck? Give Horace a sunflower seed and listen to what he shouts.