Other MCP-Compatible Clients

Any client that implements the Model Context Protocol specification can connect to the MCP server.

Generic configuration

The server communicates over stdio using the MCP JSON-RPC protocol. Configure your client to start the binary and pass your credentials as environment variables:

Parameter	Value
Transport	stdio (standard input/output: the server runs as a local process on your machine)
Command	/path/to/ionoscloud-mcp
IONOS_TOKEN	Your IONOS CLOUD API token (required)
IONOS_S3_ACCESS_KEY	Your Object Storage access key (optional)
IONOS_S3_SECRET_KEY	Your Object Storage secret key (optional)

JSON format

Most MCP clients use a JSON configuration similar to:

{
  "mcpServers": {
    "ionoscloud": {
      "command": "/path/to/ionoscloud-mcp",
      "env": {
        "IONOS_TOKEN": "your-api-token"
      }
    }
  }
}

Refer to your client's documentation for the exact configuration format and file location.

For programmatic use via the Anthropic SDK or other LLM APIs, see the MCP SDK documentation for how to connect to a stdio-based MCP server as a subprocess.

Tool discovery

The server exposes all tools through the standard MCP tools/list method. By default, all tools (including Compute Engine and Object Storage) are registered at startup. If your client has a tool-count cap or you want to defer Compute and Object Storage registration, set IONOS_MCP_LOAD_MODE=lazy; the client must support notifications/tools/list_changed to discover the additional tools after a loader-sentinel call. For more information, see Selective Tool Loading.

Clients with limitations

OpenAI Codex CLI: supports MCP via a mcpServers block in ~/.codex/config.toml (TOML format, not JSON). Stdio transport supported. GA.

ChatGPT: supports MCP only for remote HTTP/SSE servers, not local stdio binaries. The MCP server runs locally over stdio; you cannot connect it directly to ChatGPT without a public HTTPS endpoint. Not supported for typical developer setups.

n8n: can call stdio MCP servers as an MCP client from within an n8n workflow using the MCP Client node. However, the n8n MCP Server Trigger (for exposing n8n as an MCP server) does not support stdio. If your workflow needs to call the MCP server, configure the MCP Client node with the binary path and credentials.