How to properly configure SAP CAP MCP Server so Codex can detect it?

[fabi2295]

I'm trying to configure Codex to detect and use the SAP CAP MCP Server, but Codex keeps saying that no MCP server is running, even though I can start it manually and see it listening on a port.

Here is what I tried so far:

mcp.json

{
"servers": {
"cds-mcp": {
"command": "npx",
"args": ["-y", "@cap-js/mcp-server"],
"env": {},
"type": "stdio"
}
},
"inputs": []
}

The SAP CAP MCP server appears to run correctly (screenshot attached), but Codex still reports:

config.toml (Codex)

[tools.mcp-server-cap]
type = "mcp"
command = "cds-mcp"
args = ["--port", "4005"]

Question

Has anyone managed to configure Codex with the CAP MCP server?
Is there something obvious I'm missing. Perhaps related to TCP vs STDIO mode or how Codex expects MCP servers to be declared?

Any help or working example would be greatly appreciated.

[MioYasutake · Accepted solution]

@fabi2295 

Here's my config.toml settings:

[mcp_servers.cds-mcp]
command = "npx"
args = ["-y", "@cap-js/mcp-server"]

Also, try running the `codex` command before using the Codex plugin.