This example connects Codex to the read-only parts of a Neuron’s file server. You do not need to retrieve an OAuth token yourself.
Before you start
Install a current Codex client and obtain this connection profile from the Neuron operator:
If the Neuron is yours, follow Connect to a local Neuron first.
Installing a Neuron does not by itself guarantee a Codex-compatible OAuth client-registration path. The operator must configure either a static client for Codex or working DCR before this login can succeed.
1. Add the endpoint
When you have a pre-registered client ID:
When the operator has confirmed automatic OAuth client registration (CIMD or DCR):
2. Sign in
Start the OAuth flow:
Codex opens the Neuron’s sign-in and authorization flow. Complete it in the browser. Codex stores the resulting credentials; do not copy an access token into the command or configuration file. When both CIMD and DCR are available, Codex chooses automatically. Use codex mcp login --help before forcing a registration method for an operator-specific setup.
See the official Codex MCP reference for the current client flags, OAuth selection rules, and configuration-file format.
3. Verify the connection
Inside Codex, run /mcp. Confirm neuron-files is connected, then ask:
If login, discovery, or permissions fail, use Troubleshoot MCP.
Use a different server
Replace the endpoint and OAuth connection profile with those supplied for /MCP/EventLog, /MCP/Content, or /MCP/XMPP. Do not assume these servers are deployed or that the same role grants access to every one. 
