Move from OpenRouter

The exchange serves the OpenAI Chat Completions format, so most OpenRouter code changes in two places: the base URL and the API key. The exchange is an auction. It does not send your request to a fixed provider, so read What is different about money before you send traffic.

Change these two things

1. Issue a spend key on the API keys page. See API keys.
2. Set the base URL to https://router.inference.ai.exchange/v1. Send the key as Authorization: Bearer sk-liquid-….

from openai import OpenAI

client = OpenAI(
    base_url="https://router.inference.ai.exchange/v1",
    api_key="sk-liquid-...",
)

Then check three more things:

• Change each model to a name that GET /v1/models lists. A name such as openai/gpt-oss-120b does not work.
• Move each provider setting to the exchange object. See Routing settings.
• Run a dry run, then send a small request. See Check a request without a purchase.

What differs

• Model names. The exchange has no vendor/model names. To limit the models to one creator, use exchange.candidates.creators.allow.
• Fallbacks. The models list is ignored. Send architect.basket with exchange.candidates.models.allow.
• Suffixes. Use :web (beta) instead of :online. :nitro and :floor return 404 model_not_found. To rank the offers, use :fastest or :cheapest. See Axis routing.
• Money. The exchange fixes a price cap per job. See below.

What is different about money

The exchange fixes a price cap before the first token. The cap is the most the job can cost. The exchange holds that amount from your workspace balance, charges the tokens used, and returns the rest. See Quickstart.

• Send exchange.cap_usd to set your own cap. An offer with a higher worst-case charge does not compete.
• The x-liquid-cap-usd header and exchange.charge.cap_usd give the cap. exchange.charge.total_usd gives the charge.
• If the cheapest eligible cap is more than the balance, the response is 402 insufficient_balance. needed_usd is the lowest cap that an offer holds for your limit. If the key reached its spending limit, the response is 402 budget_exhausted.
• If an output limit that you set does not fit your cap, the response is 400 no_eligible_offer with param set to exchange.cap_usd. The message gives the lowest cap that fits.
• The exchange never lowers an output limit that you set. It refuses the request.
• If you set no output limit, the exchange chooses one. It lowers the limit to what an offer allows, and halves it when your balance or cap excludes every offer. It stops at 1,024 tokens.

Output limits has the exact rule.

Check a request without a purchase

POST /v1/exchange/dry-run shows which offers would compete, in award order, and why the others are left out. It places no job and holds no funds. It takes model and an exchange object, and it does not read provider.

curl https://router.inference.ai.exchange/v1/exchange/dry-run \
  -H "Authorization: Bearer $LIQUID_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-oss-120b",
    "exchange": { "candidates": { "providers": { "allow": ["acme"] } }, "cap_usd": 0.05 }
  }'

Example

An OpenRouter request:

{
  "model": "openai/gpt-oss-120b",
  "messages": [{ "role": "user", "content": "Say hello." }],
  "provider": {
    "only": ["acme"],
    "ignore": ["slow-*"],
    "max_price": { "prompt": 1, "completion": 2 },
    "data_collection": "deny",
    "sort": "price"
  }
}

The same request for the exchange. The model name is an illustration:

{
  "model": "gpt-oss-120b",
  "messages": [{ "role": "user", "content": "Say hello." }],
  "exchange": {
    "candidates": {
      "providers": { "allow": ["acme"], "exclude": ["slow-*"] }
    },
    "limits": { "price": { "input_usd_per_mtok": 1, "output_usd_per_mtok": 2 } },
    "privacy": { "retention": "none" },
    "rank": { "strategy": { "kind": "price" } },
    "cap_usd": 0.05
  }
}

Reference

Model names

The model field accepts a model, a router model, a basket or a preset. Connect an app has the table. An unknown name returns 404 model_not_found with suggestions. The exchange never uses a different model.

Routing settings

The exchange reads a provider object and applies each setting that it can apply exactly. Purchasing rules has the only table of every setting. In short:

• The exchange maps max_price.prompt, max_price.completion, only, ignore, order, data_collection: "deny", zdr: true and sort: "price".
• order tries its providers first, then the rest of the market. With allow_fallbacks: false, only the providers in order compete. See Preferred providers.
• require_parameters and allow_fallbacks: true change nothing.
• It refuses every other setting. One 400 unsupported_parameter answer lists all of them.
• provider can only narrow what exchange, the key preset and the workspace guardrails allow.
• An ignore name must be a provider handle, or a pattern with *.

A refused setting can have an exchange field to use instead:

Other OpenRouter fields

Troubleshooting