Rewalto MCP in Claude Desktop

Get an API key

1. Create an API key for your organisation, as the API keys guide explains. Its secret is shown once, when the key is created; copy it then.
2. For an agent that only reads, give the key data:read and usage:read. Add tools:run only for an agent allowed to propose and approve spending.
3. Every request to the MCP server needs the key, the free catalogue tools included. Put it in the placeholder below (rwk_your_key, or the environment variable the snippet names).

See API keys for how to create, list and revoke a key.

Add Rewalto to Claude Desktop

In Claude Desktop, open Settings, then Developer, then Edit Config. That opens claude_desktop_config.json: on macOS ~/Library/Application Support/Claude/claude_desktop_config.json, on Windows %APPDATA%\Claude\claude_desktop_config.json.

{
  "mcpServers": {
    "rewalto": {
      "command": "npx",
      "args": ["mcp-remote", "https://mcp.rewalto.com/mcp", "--header", "Authorization:${AUTH_HEADER}"],
      "env": { "AUTH_HEADER": "Bearer rwk_your_key" }
    }
  }
}

Claude Desktop's config file starts local programs, so the server is reached through mcp-remote, an open-source bridge that runs with Node.js and sends the header on every request.

Leave no space after Authorization: inside args; the space belongs in AUTH_HEADER, as mcp-remote's own instructions advise. Quit and reopen Claude Desktop after saving.

Claude's custom connectors take the server address alone and use Sign in with Rewalto instead of an API key.

Check the connection

1. Reach the server. Open Settings, then Developer: rewalto is listed as running, and its tools appear in the chat's tool menu. Rewalto's live tool list has 102 tools; the ones marked for a signed-in dashboard only are refused to an API key. If it shows an error, the key is missing or not accepted: the server answers 401 to a request without a valid key.
2. Call a free tool. Ask the agent: "Use Rewalto's list_catalogue_categories tool and list the categories." The tool is free and spends no credits.
3. Read a result. The answer lists Rewalto's catalogue categories. They match the public list at https://api.rewalto.com/v1/catalogue/categories, which needs no key.

Check the key from a terminal

curl -sS https://mcp.rewalto.com/mcp \
  -H 'content-type: application/json' -H 'accept: application/json, text/event-stream' \
  -H "authorization: Bearer $REWALTO_API_KEY" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"whoami","arguments":{}}}'

The answer names your organisation, with credential kind api_key and the key's permissions. It spends nothing.