# Liquid MCP

> Give your agent the exchange as tools. It reads prices, previews a purchase and buys an answer, an image or a video. You set the most that it can spend.

Page: https://liquidinference.ai/mcp

## Connect

The server uses the Streamable HTTP transport at:

```
https://router.inference.ai.exchange/mcp
```

Add that address to an MCP client. The client opens the browser, and you choose the workspace, whether the agent can buy, and the most that it can spend. The exchange gives the client its own API key. There is no key to paste.

```bash
liquid mcp claude
claude mcp add --transport http liquid https://router.inference.ai.exchange/mcp
claude mcp login liquid
```

The first command uses the [Liquid CLI](https://liquidinference.ai/cli.md) and also works with `codex`, `cursor` and `opencode`. The last two commands add the server to Claude Code by hand.

## Tools

The server has 24 tools. Each one sends an ordinary request through the router with the key of the agent, so the price caps, the key limits and the billing are the same as for the REST API.

- **Look at the market:** `list_models`, `get_model`, `compare_models`, `get_book`, `get_markets`, `get_routers`, `get_fills`, `get_volume`, `get_throughput`, `get_lifetime`. Any key.
- **Preview a purchase:** `dry_run`, `count_tokens`. They buy nothing.
- **Read your account:** `get_balance`, `get_limits`, `list_receipts`, `get_job`.
- **Buy:** `send_message`, `generate_image`, `generate_speech`, `create_video`, `transcribe`, `decide`, `embed`. These need a key that can spend. `get_video` reads the status of a video job.

A client that supports MCP Apps shows a widget for the market tools, `get_balance`, `get_limits`, `list_receipts`, `get_job`, `dry_run` and the tools that make media. A widget never buys.

## Control

The key is named `Liquid MCP: <app name>` and expires in 7 days. You can revoke it at any time on the API keys page. The default spend limit is $10. If you do not allow buying, the key can look up models and the book and read the balance and receipts. A tool that buys also takes `cap_usd`, which is the most that one job can cost.

## For client authors

- A request to `/mcp` with no key gets `401` and a `WWW-Authenticate` header that names the resource metadata (RFC 9728) at `/.well-known/oauth-protected-resource/mcp`.
- The client registers (RFC 7591) or uses the address of a metadata document as its `client_id`. PKCE with `S256` is required.
- The scopes are `mcp:read` and `mcp:spend`. A tool that buys on a read-only key gets `403` with `insufficient_scope`.
- The token response has the key as `access_token`. There are no refresh tokens.

## More

- [MCP guide](https://liquidinference.ai/docs/connect-mcp-server.md): every tool, the sign-in and the errors.
- [API keys](https://liquidinference.ai/docs/keys.md): scopes, limits and expiry.
- [Home](https://liquidinference.ai/index.md)