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.

[warren_chan]

To clarify for the general audience, the Summary skill returning the same thing issue was fixed last month in Platform AI Agents and Skills [sn_uxc_gen_ai] 12.0.12. Update to this version to get that fix.

[warren_chan]

I remind everyone not to conflate the ServiceNow MCP client with the ServiceNow MCP server. 

MCP client = ServiceNow AI agent tool making outbound MCP tool calls to an external MCP server

MCP server = ServiceNow Now Assist Skills being served through a ServiceNow instance for consumption by clients like Claude Desktop, Postman MCP, perhaps even another ServiceNow instance

The aforementioned KB2676985: Request access to the MCP service for MCP Server Console is for the latter functionality. 

[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.

[arielgritti]

Hi all,

I've a similar issue; I'm able to connect from Postman (as a MCP client) and MS Copilot (as a MCP client) and see the AI Skill (incident summarization) but I'm getting 403 forbidden.

I just created this question in the community: https://www.servicenow.com/community/now-assist-forum/403-forbidden-when-calling-an-ai-skill-form-a-...

My scenario:
OAuth Client Credentials (with an integration user with ITIL role)
AI Skill (OOTB) requires ITIL role

Token is generated OK
I'm able to "connect" from both MCP clients (Postman and MS Copilot)
The "tool" is available

When trying to execute, 403 forbidden is the error.

Any help, guidance is welcome.
Thanks,
Ariel