When adding an MCP server in CX Agent Studio, it’s unable to list any MCP tools. A notification appears which states:
Failed to initialize MCP session for Fetch: Client failed to initialize by explicit API call
When doing this from the tool tester UI, a red error message states:
Failed to retrieve tools for toolset: projects/…./locations/us/apps/…./toolsets/…..
Debugging on our own MCP server, I can see that google is reaching out and doing the MCP initialize / notifications/initialized cycle using the modelcontextprotocol/java-sdk(version 1.0.0). It appears to be doing multiple requests. However, something is preventing it from doing the tools/list request.
Our MCP server uses the latest type modelcontextprotocol/sdk(v1.29.0). Other public MCP servers appear to fail with a similar error.
Any suggestions on what may be happening? We’ve been able to integrate our MCP server in multiple different clients, so I’m leaning towards an issue on the google side, but would definitely be open to correct anything on our end if we have to.