Solved

MCP Server not sending properly formatted responses

Forum|Forum|21 days ago
February 4, 2026
3 replies
30 views

+2

Jake Colman

I connected the MCP Server to Cursor using HTTPS. Cursor successfully connects and shows that 6 tools are available. However, when I make a request I am not getting back a response. I reconnected using the NPM package and it does work successfully, but only 3 tools are available. How do I get the HTTPS Server working in Cursor?

Best answer by Jake Colman

This issue has been fixed by the development team and it’s now working correctly.

O

ofreyssinet
Forum|Forum|20 days ago
February 4, 2026

Hello, same issue here:

Description:

When using the Lucid MCP server with Cursor IDE, all tool calls (search, fetch) fail with the following error:

MCP error -32600: Tool search has an output schema but did not return structured content

Environment:

Client: Cursor IDE (latest version)

OS: macOS (darwin 25.2.0)

MCP Server: Lucid Software (official integration via Cursor's MCP settings)

Steps to Reproduce:

Enable the Lucid Software MCP server in Cursor IDE (Settings → Features → MCP)
Complete OAuth authentication successfully
Attempt to use any Lucid MCP tool (e.g., search with query "document" or fetch with a valid document ID)
Observe the error

Tools Tested:

search with various queries ("document", "a", "") - all fail

fetch with a valid document UUID - also fails

Expected Behavior:

The tools should return search results or document content as specified in their output schemas.

Actual Behavior:

All tool calls return the generic MCP error: "Tool [toolName] has an output schema but did not return structured content"

Like

+15

Leianne C
Lucid support team
Forum|Forum|20 days ago
February 5, 2026

Hi @Jake Colman and @ofreyssinet, thank you for posting in the community. I see that you have both submitted support tickets for the issues you are experiencing, and someone from our team is assisting you. Please refer to the ticket for further information.

For anyone else reading this, we have reported this to our development team. I apologize for any disruption this may cause, and we will update this thread with any new information about a fix. Please follow along on this thread for updates, and post any additional questions or concerns below.