Codex CLI

Add the server

codex mcp add vike-trader -- vike-cli mcp --node 127.0.0.1:7879

The form is codex mcp add <name> [--env KEY=VALUE] -- <command and its arguments>. Everything after the -- is the stdio command Codex will launch, so --node lands on vike-cli rather than being claimed by codex mcp add.

Or edit the file

~/.codex/config.toml is the default; a trusted project can carry its own .codex/config.toml. The server is a table named after it:

[mcp_servers.vike-trader]
command = "vike-cli"
args = ["mcp", "--node", "127.0.0.1:7879"]

Both vike-cli mcp flags are optional, and both only widen what the tools reach. The shortest working entry is the command alone:

[mcp_servers.vike-trader]
command = "vike-cli"
args = ["mcp"]

which still gives you the four offline authoring tools — validate_strategy, discover_params, list_templates, list_indicators. --addr <host:port> is the vike-datahub the backtest tools ship profiles to (default 127.0.0.1:7878); --node <host:port> is the running vike-tradehub the live tools observe and control, and it has no default.

If Codex reports the binary as not found, give command an absolute path — the same advice as every other client here, for the same reason: nothing guarantees your shell's PATH.

The node keys

Codex CLI runs in your terminal, so an exported VIKE_TRADEHUB_OBSERVE_KEY / VIKE_TRADEHUB_CONTROL_KEY reaches the server. Each key independently falls back to <project>/settings/secrets.env — the same store the vike-tradehub daemon reads — when the environment does not carry it, so on a configured box you usually need to export nothing at all. The resolver that applies that order is crates/vike-cli/src/cmd/nodekeys.rs's resolve.

To pin one key for this server alone rather than exporting it, the config table takes an env sub-table (and codex mcp add takes --env KEY=VALUE):

[mcp_servers.vike-trader]
command = "vike-cli"
args = ["mcp", "--node", "127.0.0.1:7879"]

[mcp_servers.vike-trader.env]
VIKE_TRADEHUB_OBSERVE_KEY = "..."

The environment wins over the store per key, so setting one there leaves the other resolving from the store. A control key is the expensive one to write into a file — it places orders — so prefer the credential store, especially for a project-scoped .codex/config.toml that sits inside a repository.

vike-cli secrets path prints which store a directory resolves to; vike-cli secrets list shows whether a key is in it, by name — never values.

Verify

codex mcp list

Then, in a session:

list the vike strategy templates

list_templates is the free check — offline, no key, no node, no network. If it answers, the subprocess is running and the protocol is working, and anything still failing is an address or a key rather than the setup. With a node configured, follow it with "show me the node snapshot" to prove the observe key too.

Troubleshooting

The --node flag is rejected. It is on the wrong side of the --. Everything before the double dash belongs to codex mcp add; everything after it belongs to vike-cli.

A JSON block was pasted into config.toml. See the callout above — this is the failure mode this client has and the others do not, because every MCP setup snippet on the internet is JSON.

The offline tools work and the node tools do not. That is an address or a key, not the MCP wiring, and the two failures are worded differently on purpose: "no vike-tradehub node configured" means --node never arrived, while "set neither in the process environment nor in the credential store" names a key and names both places it looked.

A write tool answered but nothing happened. That is not a Codex problem. A write executes only when a call carries both confirm: true and the preview_token its own preview returned; anything less comes back as another preview, with will_execute: false and no error. Live node is the contract.

Where this shape came from

The config path, the [mcp_servers.<name>] table with command/args/env, and the codex mcp add <name> --env … -- <command> form were read from OpenAI's own Codex MCP documentation (developers.openai.com/codex/mcp, which now redirects into the ChatGPT docs) in September 2026, not from memory. If Codex has changed since, that page is the authority and this one is the copy.

The data server too

Codex holds both Vike servers in the same config.toml — the hosted data server as a url-carrying table beside this one. Data client setup has its shape. Give the two tables different names.