Server details
| Field | Value |
|---|---|
| URL | https://docs.arcus.xyz/mcp |
| Transport | HTTP (streamable) |
| Authentication | OAuth 2.0 with dynamic client registration |
| Discovery | /.well-known/oauth-protected-resource |
Browsing the MCP URL directly in a browser returns
401 invalid_token — that is the standard MCP-spec advertisement of the OAuth flow (RFC 9728). MCP clients follow the WWW-Authenticate header to complete authentication automatically; you do not need a personal access token.What you can ask
After connecting, your assistant can answer questions grounded in the live spec:API behavior
“Which endpoint takes TP/SL —
placeOrder or batchPlaceOrder?”Auth flow
“Show me how to sign a request with my Ed25519 API key.”
WebSocket channels
“What channels stream order book updates and what do their payloads look like?”
Code samples
“Give me a TypeScript snippet that cancels all open orders for one market.”
Connect your editor
Claude Code
Remote MCP via
claude mcp add.Cursor
Add through Cursor MCP settings.
Windsurf
Configure in Cascade’s MCP panel.
Troubleshooting
The browser shows 401 / invalid_token
The browser shows 401 / invalid_token
Expected. The endpoint is an OAuth-protected MCP resource; browsers do not run the MCP OAuth flow. Use a real MCP client (Claude Code, Cursor, Windsurf, Claude Desktop) — it will redirect you through a one-time authentication and then connect.
Authentication popup never opens
Authentication popup never opens
Update your client to the latest version — MCP HTTP-transport OAuth support is recent. For Claude Code:
npm i -g @anthropic-ai/claude-code. Then remove and re-add the server.The assistant gives stale answers
The assistant gives stale answers
The MCP server reflects the current published spec. If something looks wrong, open an issue and link to the page — we resync from upstream on every merge.