codex: add enableMcpIntegration option

Work with the shared mcp module for integration and transformation.

Signed-off-by: Austin Horstman <khaneliman12@gmail.com>
This commit is contained in:
Austin Horstman 2026-02-08 14:29:48 -06:00
parent b1f916ba05
commit 6c8def1df8
6 changed files with 175 additions and 3 deletions

View file

@ -26,6 +26,20 @@ in
package = lib.mkPackageOption pkgs "codex" { nullable = true; };
enableMcpIntegration = lib.mkOption {
type = lib.types.bool;
default = false;
description = ''
Whether to integrate the MCP server config from
{option}`programs.mcp.servers` into
{option}`programs.codex.settings.mcp_servers`.
Note: Settings defined in {option}`programs.mcp.servers` are merged
with {option}`programs.codex.settings.mcp_servers`, with settings-based
values taking precedence.
'';
};
settings = lib.mkOption {
# NOTE: `yaml` type supports null, using `nullOr` for backwards compatibility period
type = lib.types.nullOr tomlFormat.type;
@ -48,6 +62,15 @@ in
envKey = "OLLAMA_API_KEY";
};
};
mcp_servers = {
context7 = {
command = "npx";
args = [
"-y"
"@upstash/context7-mcp"
];
};
};
}
'';
};
@ -111,10 +134,36 @@ in
config =
let
useXdgDirectories = (config.home.preferXdgDirectories && isTomlConfig);
useXdgDirectories = config.home.preferXdgDirectories && isTomlConfig;
xdgConfigHome = lib.removePrefix config.home.homeDirectory config.xdg.configHome;
configDir = if useXdgDirectories then "${xdgConfigHome}/codex" else ".codex";
configFileName = if isTomlConfig then "config.toml" else "config.yaml";
transformedMcpServers = lib.optionalAttrs (cfg.enableMcpIntegration && config.programs.mcp.enable) (
lib.mapAttrs (
_name: server:
# NOTE: Convert shared programs.mcp fields to Codex config keys:
# - removeAttrs drops keys that Codex does not use directly
# - "disabled" becomes inverse "enabled"
# - "headers" is renamed to "http_headers"
# See: https://developers.openai.com/codex/mcp#other-configuration-options
(lib.removeAttrs server [
"disabled"
"headers"
])
// (lib.optionalAttrs (server ? headers && !(server ? http_headers)) {
http_headers = server.headers;
})
// {
enabled = !(server.disabled or false);
}
) config.programs.mcp.servers
);
settingMcpServers = lib.attrByPath [ "mcp_servers" ] { } cfg.settings;
mergedMcpServers = transformedMcpServers // settingMcpServers;
mergedSettings =
cfg.settings // lib.optionalAttrs (mergedMcpServers != { }) { mcp_servers = mergedMcpServers; };
in
mkIf cfg.enable {
assertions = [
@ -126,9 +175,10 @@ in
home = {
packages = mkIf (cfg.package != null) [ cfg.package ];
file = {
"${configDir}/${configFileName}" = lib.mkIf (cfg.settings != { }) {
source = settingsFormat.generate "codex-config" cfg.settings;
"${configDir}/${configFileName}" = lib.mkIf (mergedSettings != { }) {
source = settingsFormat.generate "codex-config" mergedSettings;
};
"${configDir}/AGENTS.md" = lib.mkIf (cfg.custom-instructions != "") {
text = cfg.custom-instructions;
@ -150,6 +200,7 @@ in
if lib.isPath content then { source = content; } else { text = content; }
)
) (if builtins.isAttrs cfg.skills then cfg.skills else { }));
sessionVariables = mkIf useXdgDirectories {
CODEX_HOME = "${config.xdg.configHome}/codex";
};