Codex CLI uses TOML, not JSON. Add the native `mcp_servers.zephex` block to `~/.codex/config.toml`.
OVERVIEW
Codex CLI (@openai/codex) is OpenAI's terminal-based coding agent. Zephex should be configured through the native TOML MCP server block with `command`, `args`, and an `[mcp_servers.zephex.env]` table holding `ZEPHEX_API_KEY`.
CONFIG FILE LOCATION
~/.codex/config.toml — TOML format, not JSON or YAML.
Append the TOML block below to `~/.codex/config.toml`.
Replace `mcp_sk_your_key_here` with your real Zephex API key.
[mcp_servers.zephex]command = "npx"args = ["-y", "zephex"] [mcp_servers.zephex.env]ZEPHEX_API_KEY = "mcp_sk_your_key_here"If you prefer, let Codex generate the server section first, then edit the generated env block with your key.
codex mcp add zephex -- npx -y zephexCodex CLI reads the TOML config directly. After saving the file, start a new Codex session so it reloads the MCP server list.
Verify both the MCP connection and the live tool list before using Zephex in normal Codex sessions.
Make sure the TOML block is appended to `~/.codex/config.toml` and restart the Codex CLI session after saving.
The config uses TOML, not JSON. Keep the section headers exactly as shown: `[mcp_servers.zephex]` and `[mcp_servers.zephex.env]`.
Try `codex mcp debug zephex` for detailed connection logs.
Confirm the `ZEPHEX_API_KEY` value in `[mcp_servers.zephex.env]` is the real key from your dashboard.
If the editor still does not connect, return to Quickstart or check Connection Issues.