Unable to Fetch MCP Tools When Adding MCP Tool to AI Agent

[varunagarwal83]

Hello Community,

We are working on a use case where one ServiceNow instance functions as the MCP server and another as the MCP client. On the MCP server instance, we configured both the default QuickStart MCP Server and a custom MCP server through the MCP console. As part of the setup, we also created an OAuth inbound integration and configured the corresponding client settings on the MCP client instance, following the steps provided in the ServiceNow documentation.
The client is able to authenticate with the server successfully, and the MCP execution logs confirm successful responses. However, when attempting to add an MCP tool to our AI Agent, we consistently receive the error message “Unable to fetch the tools for the MCP server.”
We have reviewed the configuration on both the client and server instances and verified that the MCP client and MCP server plugin versions match on both environments. Additionally, both instances are running on the same patch level:
glide‑zurich‑07‑01‑2025__patch4‑hotfix3‑12‑23‑2025.

[varunagarwal83]

Thanks @warren_chan  for sharing your understanding—I’m aligned with this. We have set up one ServiceNow instance as the MCP server, for which forwarding was enabled by ServiceNow Support, and a second instance as the MCP client, where we are consuming the MCP server tools. Prior to enabling forwarding, the MCP tools were not visible in the client instance. The tools are now available; however, they are not returning the expected results, and we are still working with support to resolve this issue.

[warren_chan]

Okay - Support is the appropriate route for your issues. I would also say that you can check that your Now Assist Skill is functioning as expected. There's a possibility of a context gap if a Now Assist Skill wasn't designed for consumption through MCP server originally.