8th Wall MCP Tool icon

8th Wall MCP Tool

Invoke tools exposed by the 8th Wall MCP HTTP bridge

Overview

This node allows you to invoke tools exposed by the 8th Wall MCP HTTP bridge via HTTP requests. It is designed to interact with various backend tools provided by the 8th Wall platform, enabling automation and integration within n8n workflows.

Common scenarios include:

  • Performing health checks on the 8th Wall MCP service.
  • Triggering specific backend tools or services exposed by the MCP bridge.
  • Passing JSON parameters dynamically to control tool behavior.

For example, you might use this node to periodically ping the MCP service to ensure it is operational or to send commands to add 3D models or scenes if such tools are available on the MCP bridge.

Properties

Name Meaning
Tool Select the tool to invoke from a dynamically loaded list of available tools (e.g., "health_ping").
Use Custom Tool Name Enable to manually enter a custom tool name instead of selecting from the list.
Tool Name (Custom) The custom tool name to call, as exposed by the MCP bridge (visible only if "Use Custom Tool Name" is enabled).
JSON Parameters Choose whether to pass tool arguments as JSON (default: true).
Args (JSON) JSON object containing the arguments to pass to the selected tool (visible only if "JSON Parameters" is true).

Output

The node outputs an array of items where each item contains a json field representing the response from the called tool.

  • If the tool returns a result, the output JSON will contain the result field's value.
  • If the tool does not return a result field, the entire response is returned as-is.
  • In case of failure and if "Continue On Fail" is enabled, the output JSON will contain { ok: false, error: <error message> }.

No binary data output is produced by this node.

Dependencies

  • Requires access to the 8th Wall MCP HTTP bridge endpoint, configured via credentials that provide the base URL and authentication.
  • The node makes HTTP POST requests to the MCP bridge at /tool/{toolName}.
  • The node dynamically fetches available tools from the MCP bridge at /tools for selection in the UI.

Troubleshooting

  • Common issues:

    • Incorrect or unreachable MCP bridge URL can cause connection failures.
    • Using an invalid or misspelled tool name will likely result in errors from the MCP bridge.
    • Malformed JSON in the "Args (JSON)" property may cause request failures.

  • Error messages:

    • Network errors or timeouts indicate connectivity problems; verify the MCP bridge URL and network access.
    • Error responses from the MCP bridge typically include an error message; these are surfaced in the node output if "Continue On Fail" is enabled.

  • Resolution tips:

    • Ensure the MCP bridge URL is correct and accessible.
    • Use the "Tool" dropdown to select valid tools or enable "Use Custom Tool Name" carefully.
    • Validate JSON input before execution.

Links and References

Discussion