Connect your AI

The MCP endpoint is https://papertrade-x402.pages.dev/mcp (Streamable HTTP, no authentication). It exposes free tools directly. Paid tools return x402 payment requirements and never pay, so connecting an assistant cannot spend money. Client configuration formats change quickly; each snippet below was checked against the client's current documentation, and if a client moves a setting, its own docs win.

Claude Code#

claude mcp add --transport http papertrade-x402 https://papertrade-x402.pages.dev/mcp

Add --scope user to make it available in every project, or commit a project-level .mcp.json:

{
  "mcpServers": {
    "papertrade-x402": { "type": "http", "url": "https://papertrade-x402.pages.dev/mcp" }
  }
}

Claude Desktop and claude.ai#

Open Settings, then Connectors, then Add custom connector, and paste https://papertrade-x402.pages.dev/mcp. No sign-in is needed.

Claude Desktop can also reach remote servers through the mcp-remote stdio bridge in claude_desktop_config.json:

{
  "mcpServers": {
    "papertrade-x402": {
      "command": "npx",
      "args": ["-y", "mcp-remote", "https://papertrade-x402.pages.dev/mcp"]
    }
  }
}

Claude API (MCP connector)#

The connector is a beta. Current header: mcp-client-2025-11-20. Declare the server in mcp_servers and enable it with an mcp_toolset entry:

curl https://api.anthropic.com/v1/messages \
  -H "x-api-key: $ANTHROPIC_API_KEY" -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: mcp-client-2025-11-20" -H "content-type: application/json" \
  -d '{
    "model": "claude-opus-5-5",
    "max_tokens": 1000,
    "messages": [{"role": "user", "content": "What is the BTC liquidation picture on Papertrade right now?"}],
    "mcp_servers": [{"type": "url", "url": "https://papertrade-x402.pages.dev/mcp", "name": "papertrade-x402"}],
    "tools": [{"type": "mcp_toolset", "mcp_server_name": "papertrade-x402"}]
  }'

OpenAI Codex CLI#

Add a Streamable HTTP server to ~/.codex/config.toml:

[mcp_servers.papertrade-x402]
url = "https://papertrade-x402.pages.dev/mcp"

Or from the shell:

codex mcp add papertrade-x402 --url https://papertrade-x402.pages.dev/mcp

OpenAI Responses API#

curl https://api.openai.com/v1/responses \
  -H "Authorization: Bearer $OPENAI_API_KEY" -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-5",
    "tools": [{
      "type": "mcp",
      "server_label": "papertrade_x402",
      "server_url": "https://papertrade-x402.pages.dev/mcp",
      "require_approval": "never"
    }],
    "input": "Estimate a 100x BTC long with 100 USD margin on Papertrade."
  }'

require_approval: "never" is safe here because every tool is read-only. Use "always" if your policy requires approval for all tool calls.

ChatGPT#

Enable developer mode (Settings, Apps and Connectors, Advanced), then create a connector with the URL https://papertrade-x402.pages.dev/mcp and authentication set to none.

Gemini CLI#

In ~/.gemini/settings.json (or the project .gemini/settings.json):

{
  "mcpServers": {
    "papertrade-x402": { "httpUrl": "https://papertrade-x402.pages.dev/mcp" }
  }
}

Or: gemini mcp add --transport http papertrade-x402 https://papertrade-x402.pages.dev/mcp.

Cursor#

.cursor/mcp.json in a project, or ~/.cursor/mcp.json globally:

{
  "mcpServers": {
    "papertrade-x402": { "url": "https://papertrade-x402.pages.dev/mcp" }
  }
}

VS Code#

.vscode/mcp.json:

{
  "servers": {
    "papertrade-x402": { "type": "http", "url": "https://papertrade-x402.pages.dev/mcp" }
  }
}

Windsurf#

~/.codeium/windsurf/mcp_config.json:

{
  "mcpServers": {
    "papertrade-x402": { "serverUrl": "https://papertrade-x402.pages.dev/mcp" }
  }
}

Zed#

In Zed settings.json:

{
  "context_servers": {
    "papertrade-x402": { "url": "https://papertrade-x402.pages.dev/mcp" }
  }
}

Cline#

In cline_mcp_settings.json:

{
  "mcpServers": {
    "papertrade-x402": { "url": "https://papertrade-x402.pages.dev/mcp", "type": "streamableHttp" }
  }
}

Goose#

Run goose configure, choose Add Extension, then Remote Extension (Streaming HTTP), and enter the endpoint. Or in ~/.config/goose/config.yaml:

extensions:
  papertrade-x402:
    enabled: true
    type: streamable_http
    name: papertrade-x402
    uri: https://papertrade-x402.pages.dev/mcp
    timeout: 300

Continue#

.continue/mcpServers/papertrade-x402.yaml:

name: Papertrade x402
version: 0.0.1
schema: v1
mcpServers:
  - name: papertrade-x402
    type: streamable-http
    url: https://papertrade-x402.pages.dev/mcp

Any other agent framework#

Anything that speaks OpenAPI can import /openapi.json. Anything that speaks x402 can read /.well-known/x402. Frameworks that take a plain tool list can read tools/list from the MCP endpoint and map each inputSchema to a function definition.

Try it#

After connecting, ask: "Use Papertrade to show current markets, then preview the liquidation map around BTC." Both calls are free and return live data. Paying for the full answer is a separate, explicit step you or your agent take with your own wallet: see Paying as an agent.