Pi

Pi is a terminal coding agent. It uses the OpenAI Chat Completions format.

Pi has no setting for a custom base URL. Each provider and each of its models must be in ~/.pi/agent/models.json. The block below reads the live model list and adds the exchange as a provider.

Start with the Liquid CLI

The Liquid CLI can start Pi with the exchange as its provider. Pi keeps its settings in a file, so set it up one time with the steps below. liquid connect pi prints the same setup with your model filled in. Then start Pi with liquid pi.

curl -fsSL https://inference.ai.exchange/cli/install.sh | bash
liquid login
liquid connect pi
liquid pi

Before you start

• A workspace with a balance and a spend key. See API keys.
• Node.js 22.19 or newer, and jq.
• Pi installed. The package is @earendil-works/pi-coding-agent:

# installer
curl -fsSL https://pi.dev/install.sh | sh

# or with npm
npm install -g --ignore-scripts @earendil-works/pi-coding-agent

1. Write the provider

Pi does not read /v1/models. It asks for 16,384 output tokens if a model does not set maxTokens. Some offers register a lower limit. This block:

• Reads the text models of the book. Pi sends each model to the chat endpoint, so it cannot use an image, speech or video model.
• Keeps the other providers in the file.
• Writes contextWindow, maxTokens, reasoning and input from each model.

apiKey is the literal $LIQUID_API_KEY, which Pi expands at run time. The block sends the key on the models request, so the list includes your presets.

export LIQUID_API_KEY=sk-liquid-...
mkdir -p ~/.pi/agent && touch ~/.pi/agent/models.json
curl -fsSL "https://router.inference.ai.exchange/v1/models?kind=text" -H "Authorization: Bearer $LIQUID_API_KEY" | jq --slurpfile cur ~/.pi/agent/models.json '
  .data as $book | ($cur[0] // {}) | .providers.liquid = {
    baseUrl: "https://router.inference.ai.exchange/v1",
    api: "openai-completions",
    apiKey: "$LIQUID_API_KEY",
    headers: { "x-liquid-cap-usd": "1.00" },
    models: [$book[] | (.liquid_supported_parameters // []) as $p | {
      id,
      contextWindow: (.max_input_tokens // 128000),
      maxTokens: (.max_tokens // 16384),
      reasoning: ($p | index("reasoning.effort") != null),
      input: (if ($p | index("input.image")) then ["text", "image"] else ["text"] end)
    }]
  }' > ~/.pi/agent/models.json.new && mv ~/.pi/agent/models.json.new ~/.pi/agent/models.json

It writes one provider, liquid, with a baseUrl that ends in /v1 and api set to openai-completions. Run the block again when the book changes. It replaces only that provider.

2. Run it

pi --model liquid/liquid.auto

Choosing a model

Step 2 starts Pi on liquid/liquid.auto. In a session, /model changes the model. To set the reasoning effort for one launch, add it to the end of the id:

pi --model liquid/liquid.auto:high

off sends no effort. Pi sends xhigh as high.

To make a model the default, set defaultProvider to liquid and defaultModel to the model id in ~/.pi/agent/settings.json.

To get the current names, see the Market page or use GET /v1/models. See Market data. The exchange refuses a name that is not on the book. It never uses another model.

Control the cost

The provider sends x-liquid-cap-usd on each request, including liquid.auto. To change it, edit the header in providers.liquid.headers in ~/.pi/agent/models.json. The cap applies to each request, not the session. The provider step resets this value each time you run it.

The exchange fixes the cap before the first token and returns it in the x-liquid-cap-usd response header. To limit the total spend, set a spending limit on the key. See API keys and Purchasing rules.

Troubleshooting

Next steps

• Codex: the same idea for OpenAI's terminal agent.
• API keys: scopes and spending limits.
• Purchasing rules: cost caps and service floors.